Merge branch 'master' into feature/rank-eval

buildSrc/src/main/groovy/org/elasticsearch/gradle/BuildPlugin.groovy

@@ -28,6 +28,7 @@ import org.gradle.api.Task
 import org.gradle.api.XmlProvider
 import org.gradle.api.artifacts.Configuration
 import org.gradle.api.artifacts.ModuleDependency
+import org.gradle.api.artifacts.ModuleVersionIdentifier
 import org.gradle.api.artifacts.ProjectDependency
 import org.gradle.api.artifacts.ResolvedArtifact
 import org.gradle.api.artifacts.dsl.RepositoryHandler
@@ -294,12 +295,15 @@ class BuildPlugin implements Plugin<Project> {
      * Returns a closure which can be used with a MavenPom for fixing problems with gradle generated poms.
      *
      * <ul>
-     *     <li>Remove transitive dependencies (using wildcard exclusions, fixed in gradle 2.14)</li>
-     *     <li>Set compile time deps back to compile from runtime (known issue with maven-publish plugin)
+     *     <li>Remove transitive dependencies. We currently exclude all artifacts explicitly instead of using wildcards
+     *         as Ivy incorrectly translates POMs with * excludes to Ivy XML with * excludes which results in the main artifact
+     *         being excluded as well (see https://issues.apache.org/jira/browse/IVY-1531). Note that Gradle 2.14+ automatically
+     *         translates non-transitive dependencies to * excludes. We should revisit this when upgrading Gradle.</li>
+     *     <li>Set compile time deps back to compile from runtime (known issue with maven-publish plugin)</li>
      * </ul>
      */
     private static Closure fixupDependencies(Project project) {
-        // TODO: remove this when enforcing gradle 2.14+, it now properly handles exclusions
+        // TODO: revisit this when upgrading to Gradle 2.14+, see Javadoc comment above
         return { XmlProvider xml ->
             // first find if we have dependencies at all, and grab the node
             NodeList depsNodes = xml.asNode().get('dependencies')
@@ -334,10 +338,19 @@ class BuildPlugin implements Plugin<Project> {
                     continue
                 }
 
-                // we now know we have something to exclude, so add a wildcard exclusion element
-                Node exclusion = depNode.appendNode('exclusions').appendNode('exclusion')
-                exclusion.appendNode('groupId', '*')
-                exclusion.appendNode('artifactId', '*')
+                // we now know we have something to exclude, so add exclusions for all artifacts except the main one
+                Node exclusions = depNode.appendNode('exclusions')
+                for (ResolvedArtifact artifact : artifacts) {
+                    ModuleVersionIdentifier moduleVersionIdentifier = artifact.moduleVersion.id;
+                    String depGroupId = moduleVersionIdentifier.group
+                    String depArtifactId = moduleVersionIdentifier.name
+                    // add exclusions for all artifacts except the main one
+                    if (depGroupId != groupId || depArtifactId != artifactId) {
+                        Node exclusion = exclusions.appendNode('exclusion')
+                        exclusion.appendNode('groupId', depGroupId)
+                        exclusion.appendNode('artifactId', depArtifactId)
+                    }
+                }
             }
         }
     }

buildSrc/src/main/groovy/org/elasticsearch/gradle/doc/DocsTestPlugin.groovy

@@ -38,7 +38,7 @@ public class DocsTestPlugin extends RestTestPlugin {
              * the last released version for docs. */
             '\\{version\\}':
                 VersionProperties.elasticsearch.replace('-SNAPSHOT', ''),
-            '\\{lucene_version\\}' : VersionProperties.lucene,
+            '\\{lucene_version\\}' : VersionProperties.lucene.replaceAll('-snapshot-\\w+$', ''),
         ]
         Task listSnippets = project.tasks.create('listSnippets', SnippetsTask)
         listSnippets.group 'Docs'

buildSrc/src/main/groovy/org/elasticsearch/gradle/test/ClusterConfiguration.groovy

@@ -62,6 +62,15 @@ class ClusterConfiguration {
     @Input
     boolean debug = false
 
+    /**
+     * if <code>true</code> each node will be configured with <tt>discovery.zen.minimum_master_nodes</tt> set
+     * to the total number of nodes in the cluster. This will also cause that each node has `0s` state recovery
+     * timeout which can lead to issues if for instance an existing clusterstate is expected to be recovered
+     * before any tests start
+     */
+    @Input
+    boolean useMinimumMasterNodes = true
+
     @Input
     String jvmArgs = "-Xms" + System.getProperty('tests.heap.size', '512m') +
             " " + "-Xmx" + System.getProperty('tests.heap.size', '512m') +
@@ -95,11 +104,11 @@ class ClusterConfiguration {
     @Input
     Closure waitCondition = { NodeInfo node, AntBuilder ant ->
         File tmpFile = new File(node.cwd, 'wait.success')
-        ant.echo("==> [${new Date()}] checking health: http://${node.httpUri()}/_cluster/health?wait_for_nodes=>=${numNodes}")
+        ant.echo("==> [${new Date()}] checking health: http://${node.httpUri()}/_cluster/health?wait_for_nodes=>=${numNodes}&wait_for_status=yellow")
         // checking here for wait_for_nodes to be >= the number of nodes because its possible
         // this cluster is attempting to connect to nodes created by another task (same cluster name),
         // so there will be more nodes in that case in the cluster state
-        ant.get(src: "http://${node.httpUri()}/_cluster/health?wait_for_nodes=>=${numNodes}",
+        ant.get(src: "http://${node.httpUri()}/_cluster/health?wait_for_nodes=>=${numNodes}&wait_for_status=yellow",
                 dest: tmpFile.toString(),
                 ignoreerrors: true, // do not fail on error, so logging buffers can be flushed by the wait task
                 retries: 10)

buildSrc/src/main/groovy/org/elasticsearch/gradle/test/ClusterFormationTasks.groovy

@@ -73,8 +73,8 @@ class ClusterFormationTasks {
         }
         // this is our current version distribution configuration we use for all kinds of REST tests etc.
         String distroConfigName = "${task.name}_elasticsearchDistro"
-        Configuration distro = project.configurations.create(distroConfigName)
-        configureDistributionDependency(project, config.distribution, distro, VersionProperties.elasticsearch)
+        Configuration currentDistro = project.configurations.create(distroConfigName)
+        configureDistributionDependency(project, config.distribution, currentDistro, VersionProperties.elasticsearch)
         if (config.bwcVersion != null && config.numBwcNodes > 0) {
             // if we have a cluster that has a BWC cluster we also need to configure a dependency on the BWC version
             // this version uses the same distribution etc. and only differs in the version we depend on.
@@ -85,11 +85,11 @@ class ClusterFormationTasks {
             }
             configureDistributionDependency(project, config.distribution, project.configurations.elasticsearchBwcDistro, config.bwcVersion)
         }
-
-        for (int i = 0; i < config.numNodes; ++i) {
+        for (int i = 0; i < config.numNodes; i++) {
             // we start N nodes and out of these N nodes there might be M bwc nodes.
             // for each of those nodes we might have a different configuratioon
             String elasticsearchVersion = VersionProperties.elasticsearch
+            Configuration distro = currentDistro
             if (i < config.numBwcNodes) {
                 elasticsearchVersion = config.bwcVersion
                 distro = project.configurations.elasticsearchBwcDistro
@@ -252,9 +252,17 @@ class ClusterFormationTasks {
                 'path.repo'                    : "${node.sharedDir}/repo",
                 'path.shared_data'             : "${node.sharedDir}/",
                 // Define a node attribute so we can test that it exists
-                'node.attr.testattr'                : 'test',
+                'node.attr.testattr'           : 'test',
                 'repositories.url.allowed_urls': 'http://snapshot.test*'
         ]
+        // we set min master nodes to the total number of nodes in the cluster and
+        // basically skip initial state recovery to allow the cluster to form using a realistic master election
+        // this means all nodes must be up, join the seed node and do a master election. This will also allow new and
+        // old nodes in the BWC case to become the master
+        if (node.config.useMinimumMasterNodes && node.config.numNodes > 1) {
+            esConfig['discovery.zen.minimum_master_nodes'] = node.config.numNodes
+            esConfig['discovery.initial_state_timeout'] = '0s' // don't wait for state.. just start up quickly
+        }
         esConfig['node.max_local_storage_nodes'] = node.config.numNodes
         esConfig['http.port'] = node.config.httpPort
         esConfig['transport.tcp.port'] =  node.config.transportPort

buildSrc/src/main/groovy/org/elasticsearch/gradle/test/RestIntegTestTask.groovy

@@ -55,7 +55,9 @@ public class RestIntegTestTask extends RandomizedTestingTask {
         parallelism = '1'
         include('**/*IT.class')
         systemProperty('tests.rest.load_packaged', 'false')
-        systemProperty('tests.rest.cluster', "${-> nodes[0].httpUri()}")
+        // we pass all nodes to the rest cluster to allow the clients to round-robin between them
+        // this is more realistic than just talking to a single node
+        systemProperty('tests.rest.cluster', "${-> nodes.collect{it.httpUri()}.join(",")}")
         systemProperty('tests.config.dir', "${-> nodes[0].confDir}")
         // TODO: our "client" qa tests currently use the rest-test plugin. instead they should have their own plugin
         // that sets up the test cluster and passes this transport uri instead of http uri. Until then, we pass

buildSrc/src/main/resources/checkstyle_suppressions.xml

@@ -459,7 +459,6 @@
   <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]rest[/\\]RestController.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]rest[/\\]action[/\\]cat[/\\]RestCountAction.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]rest[/\\]action[/\\]cat[/\\]RestIndicesAction.java" checks="LineLength" />
-  <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]rest[/\\]action[/\\]cat[/\\]RestNodesAction.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]rest[/\\]action[/\\]cat[/\\]RestShardsAction.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]rest[/\\]action[/\\]cat[/\\]RestThreadPoolAction.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]script[/\\]ScriptContextRegistry.java" checks="LineLength" />

buildSrc/version.properties

@@ -1,5 +1,5 @@
 elasticsearch     = 6.0.0-alpha1
-lucene            = 6.2.0
+lucene            = 6.3.0-snapshot-a66a445
 
 # optional dependencies
 spatial4j         = 0.6
@@ -11,7 +11,7 @@ slf4j             = 1.6.2
 jna               = 4.2.2
 
 # test dependencies
-randomizedrunner  = 2.3.2
+randomizedrunner  = 2.4.0
 junit             = 4.11
 httpclient        = 4.5.2
 httpcore          = 4.4.5

client/rest/src/main/java/org/elasticsearch/client/HeapBufferedAsyncResponseConsumer.java

@@ -46,7 +46,7 @@ public class HeapBufferedAsyncResponseConsumer extends AbstractAsyncResponseCons
     //default buffer limit is 10MB
     public static final int DEFAULT_BUFFER_LIMIT = 10 * 1024 * 1024;
 
-    private final int bufferLimit;
+    private final int bufferLimitBytes;
     private volatile HttpResponse response;
     private volatile SimpleInputBuffer buf;
 
@@ -54,7 +54,7 @@ public class HeapBufferedAsyncResponseConsumer extends AbstractAsyncResponseCons
      * Creates a new instance of this consumer with a buffer limit of {@link #DEFAULT_BUFFER_LIMIT}
      */
     public HeapBufferedAsyncResponseConsumer() {
-        this.bufferLimit = DEFAULT_BUFFER_LIMIT;
+        this.bufferLimitBytes = DEFAULT_BUFFER_LIMIT;
     }
 
     /**
@@ -64,7 +64,14 @@ public class HeapBufferedAsyncResponseConsumer extends AbstractAsyncResponseCons
         if (bufferLimit <= 0) {
             throw new IllegalArgumentException("bufferLimit must be greater than 0");
         }
-        this.bufferLimit = bufferLimit;
+        this.bufferLimitBytes = bufferLimit;
+    }
+
+    /**
+     * Get the limit of the buffer.
+     */
+    public int getBufferLimit() {
+        return bufferLimitBytes;
     }
 
     @Override
@@ -75,9 +82,9 @@ public class HeapBufferedAsyncResponseConsumer extends AbstractAsyncResponseCons
     @Override
     protected void onEntityEnclosed(HttpEntity entity, ContentType contentType) throws IOException {
         long len = entity.getContentLength();
-        if (len > bufferLimit) {
+        if (len > bufferLimitBytes) {
             throw new ContentTooLongException("entity content is too long [" + len +
-                    "] for the configured buffer limit [" + bufferLimit + "]");
+                    "] for the configured buffer limit [" + bufferLimitBytes + "]");
         }
         if (len < 0) {
             len = 4096;

client/rest/src/main/java/org/elasticsearch/client/RestClient.java

@@ -510,6 +510,7 @@ public class RestClient implements Closeable {
 
     private static URI buildUri(String pathPrefix, String path, Map<String, String> params) {
         Objects.requireNonNull(params, "params must not be null");
+        Objects.requireNonNull(path, "path must not be null");
         try {
             String fullPath;
             if (pathPrefix != null) {

client/rest/src/test/java/org/elasticsearch/client/RequestLoggerTests.java

@@ -19,7 +19,7 @@
 
 package org.elasticsearch.client;
 
-import com.carrotsearch.randomizedtesting.generators.RandomInts;
+import com.carrotsearch.randomizedtesting.generators.RandomNumbers;
 import org.apache.http.HttpEntity;
 import org.apache.http.HttpEntityEnclosingRequest;
 import org.apache.http.HttpHost;
@@ -62,7 +62,7 @@ public class RequestLoggerTests extends RestClientTestCase {
         }
 
         HttpRequestBase request;
-        int requestType = RandomInts.randomIntBetween(getRandom(), 0, 7);
+        int requestType = RandomNumbers.randomIntBetween(getRandom(), 0, 7);
         switch(requestType) {
             case 0:
                 request = new HttpGetWithEntity(uri);
@@ -99,7 +99,7 @@ public class RequestLoggerTests extends RestClientTestCase {
             expected += " -d '" + requestBody + "'";
             HttpEntityEnclosingRequest enclosingRequest = (HttpEntityEnclosingRequest) request;
             HttpEntity entity;
-            switch(RandomInts.randomIntBetween(getRandom(), 0, 3)) {
+            switch(RandomNumbers.randomIntBetween(getRandom(), 0, 3)) {
                 case 0:
                     entity = new StringEntity(requestBody, StandardCharsets.UTF_8);
                     break;
@@ -128,12 +128,12 @@ public class RequestLoggerTests extends RestClientTestCase {
 
     public void testTraceResponse() throws IOException {
         ProtocolVersion protocolVersion = new ProtocolVersion("HTTP", 1, 1);
-        int statusCode = RandomInts.randomIntBetween(getRandom(), 200, 599);
+        int statusCode = RandomNumbers.randomIntBetween(getRandom(), 200, 599);
         String reasonPhrase = "REASON";
         BasicStatusLine statusLine = new BasicStatusLine(protocolVersion, statusCode, reasonPhrase);
         String expected = "# " + statusLine.toString();
         BasicHttpResponse httpResponse = new BasicHttpResponse(statusLine);
-        int numHeaders = RandomInts.randomIntBetween(getRandom(), 0, 3);
+        int numHeaders = RandomNumbers.randomIntBetween(getRandom(), 0, 3);
         for (int i = 0; i < numHeaders; i++) {
             httpResponse.setHeader("header" + i, "value");
             expected += "\n# header" + i + ": value";

client/rest/src/test/java/org/elasticsearch/client/RestClientIntegTests.java

@@ -229,6 +229,17 @@ public class RestClientIntegTests extends RestClientTestCase {
         }
     }
 
+    public void testPath() throws IOException {
+        for (String method : getHttpMethods()) {
+            try {
+                restClient.performRequest(method, null);
+                fail("path set to null should fail!");
+            } catch (NullPointerException e) {
+                assertEquals("path must not be null", e.getMessage());
+            }
+        }
+    }
+
     private void bodyTest(String method) throws IOException {
         String requestBody = "{ \"field\": \"value\" }";
         StringEntity entity = new StringEntity(requestBody);

client/rest/src/test/java/org/elasticsearch/client/RestClientMultipleHostsTests.java

@@ -19,7 +19,7 @@
 
 package org.elasticsearch.client;
 
-import com.carrotsearch.randomizedtesting.generators.RandomInts;
+import com.carrotsearch.randomizedtesting.generators.RandomNumbers;
 import org.apache.http.Header;
 import org.apache.http.HttpHost;
 import org.apache.http.HttpResponse;
@@ -95,7 +95,7 @@ public class RestClientMultipleHostsTests extends RestClientTestCase {
                 return null;
             }
         });
-        int numHosts = RandomInts.randomIntBetween(getRandom(), 2, 5);
+        int numHosts = RandomNumbers.randomIntBetween(getRandom(), 2, 5);
         httpHosts = new HttpHost[numHosts];
         for (int i = 0; i < numHosts; i++) {
             httpHosts[i] = new HttpHost("localhost", 9200 + i);
@@ -105,7 +105,7 @@ public class RestClientMultipleHostsTests extends RestClientTestCase {
     }
 
     public void testRoundRobinOkStatusCodes() throws IOException {
-        int numIters = RandomInts.randomIntBetween(getRandom(), 1, 5);
+        int numIters = RandomNumbers.randomIntBetween(getRandom(), 1, 5);
         for (int i = 0; i < numIters; i++) {
             Set<HttpHost> hostsSet = new HashSet<>();
             Collections.addAll(hostsSet, httpHosts);
@@ -121,7 +121,7 @@ public class RestClientMultipleHostsTests extends RestClientTestCase {
     }
 
     public void testRoundRobinNoRetryErrors() throws IOException {
-        int numIters = RandomInts.randomIntBetween(getRandom(), 1, 5);
+        int numIters = RandomNumbers.randomIntBetween(getRandom(), 1, 5);
         for (int i = 0; i < numIters; i++) {
             Set<HttpHost> hostsSet = new HashSet<>();
             Collections.addAll(hostsSet, httpHosts);
@@ -198,7 +198,7 @@ public class RestClientMultipleHostsTests extends RestClientTestCase {
             assertEquals("every host should have been used but some weren't: " + hostsSet, 0, hostsSet.size());
         }
 
-        int numIters = RandomInts.randomIntBetween(getRandom(), 2, 5);
+        int numIters = RandomNumbers.randomIntBetween(getRandom(), 2, 5);
         for (int i = 1; i <= numIters; i++) {
             //check that one different host is resurrected at each new attempt
             Set<HttpHost> hostsSet = new HashSet<>();
@@ -228,7 +228,7 @@ public class RestClientMultipleHostsTests extends RestClientTestCase {
             if (getRandom().nextBoolean()) {
                 //mark one host back alive through a successful request and check that all requests after that are sent to it
                 HttpHost selectedHost = null;
-                int iters = RandomInts.randomIntBetween(getRandom(), 2, 10);
+                int iters = RandomNumbers.randomIntBetween(getRandom(), 2, 10);
                 for (int y = 0; y < iters; y++) {
                     int statusCode = randomErrorNoRetryStatusCode(getRandom());
                     Response response;
@@ -269,7 +269,7 @@ public class RestClientMultipleHostsTests extends RestClientTestCase {
     }
 
     private static String randomErrorRetryEndpoint() {
-        switch(RandomInts.randomIntBetween(getRandom(), 0, 3)) {
+        switch(RandomNumbers.randomIntBetween(getRandom(), 0, 3)) {
             case 0:
                 return "/" + randomErrorRetryStatusCode(getRandom());
             case 1:

client/sniffer/src/test/java/org/elasticsearch/client/sniff/ElasticsearchHostsSnifferTests.java

@@ -19,7 +19,7 @@
 
 package org.elasticsearch.client.sniff;
 
-import com.carrotsearch.randomizedtesting.generators.RandomInts;
+import com.carrotsearch.randomizedtesting.generators.RandomNumbers;
 import com.carrotsearch.randomizedtesting.generators.RandomPicks;
 import com.carrotsearch.randomizedtesting.generators.RandomStrings;
 import com.fasterxml.jackson.core.JsonFactory;
@@ -69,7 +69,7 @@ public class ElasticsearchHostsSnifferTests extends RestClientTestCase {
 
     @Before
     public void startHttpServer() throws IOException {
-        this.sniffRequestTimeout = RandomInts.randomIntBetween(getRandom(), 1000, 10000);
+        this.sniffRequestTimeout = RandomNumbers.randomIntBetween(getRandom(), 1000, 10000);
         this.scheme = RandomPicks.randomFrom(getRandom(), ElasticsearchHostsSniffer.Scheme.values());
         if (rarely()) {
             this.sniffResponse = SniffResponse.buildFailure();
@@ -101,7 +101,7 @@ public class ElasticsearchHostsSnifferTests extends RestClientTestCase {
                 assertEquals(e.getMessage(), "scheme cannot be null");
             }
             try {
-                new ElasticsearchHostsSniffer(restClient, RandomInts.randomIntBetween(getRandom(), Integer.MIN_VALUE, 0),
+                new ElasticsearchHostsSniffer(restClient, RandomNumbers.randomIntBetween(getRandom(), Integer.MIN_VALUE, 0),
                         ElasticsearchHostsSniffer.Scheme.HTTP);
                 fail("should have failed");
             } catch (IllegalArgumentException e) {
@@ -175,7 +175,7 @@ public class ElasticsearchHostsSnifferTests extends RestClientTestCase {
     }
 
     private static SniffResponse buildSniffResponse(ElasticsearchHostsSniffer.Scheme scheme) throws IOException {
-        int numNodes = RandomInts.randomIntBetween(getRandom(), 1, 5);
+        int numNodes = RandomNumbers.randomIntBetween(getRandom(), 1, 5);
         List<HttpHost> hosts = new ArrayList<>(numNodes);
         JsonFactory jsonFactory = new JsonFactory();
         StringWriter writer = new StringWriter();
@@ -205,7 +205,7 @@ public class ElasticsearchHostsSnifferTests extends RestClientTestCase {
             boolean isHttpEnabled = rarely() == false;
             if (isHttpEnabled) {
                 String host = "host" + i;
-                int port = RandomInts.randomIntBetween(getRandom(), 9200, 9299);
+                int port = RandomNumbers.randomIntBetween(getRandom(), 9200, 9299);
                 HttpHost httpHost = new HttpHost(host, port, scheme.toString());
                 hosts.add(httpHost);
                 generator.writeObjectFieldStart("http");
@@ -228,7 +228,7 @@ public class ElasticsearchHostsSnifferTests extends RestClientTestCase {
             }
             if (getRandom().nextBoolean()) {
                 String[] roles = {"master", "data", "ingest"};
-                int numRoles = RandomInts.randomIntBetween(getRandom(), 0, 3);
+                int numRoles = RandomNumbers.randomIntBetween(getRandom(), 0, 3);
                 Set<String> nodeRoles = new HashSet<>(numRoles);
                 for (int j = 0; j < numRoles; j++) {
                     String role;
@@ -242,7 +242,7 @@ public class ElasticsearchHostsSnifferTests extends RestClientTestCase {
                 }
                 generator.writeEndArray();
             }
-            int numAttributes = RandomInts.randomIntBetween(getRandom(), 0, 3);
+            int numAttributes = RandomNumbers.randomIntBetween(getRandom(), 0, 3);
             Map<String, String> attributes = new HashMap<>(numAttributes);
             for (int j = 0; j < numAttributes; j++) {
                 attributes.put("attr" + j, "value" + j);
@@ -291,6 +291,6 @@ public class ElasticsearchHostsSnifferTests extends RestClientTestCase {
     }
 
     private static int randomErrorResponseCode() {
-        return RandomInts.randomIntBetween(getRandom(), 400, 599);
+        return RandomNumbers.randomIntBetween(getRandom(), 400, 599);
     }
 }

client/sniffer/src/test/java/org/elasticsearch/client/sniff/SnifferBuilderTests.java

@@ -19,7 +19,7 @@
 
 package org.elasticsearch.client.sniff;
 
-import com.carrotsearch.randomizedtesting.generators.RandomInts;
+import com.carrotsearch.randomizedtesting.generators.RandomNumbers;
 import org.apache.http.HttpHost;
 import org.elasticsearch.client.RestClient;
 import org.elasticsearch.client.RestClientTestCase;
@@ -31,7 +31,7 @@ import static org.junit.Assert.fail;
 public class SnifferBuilderTests extends RestClientTestCase {
 
     public void testBuild() throws Exception {
-        int numNodes = RandomInts.randomIntBetween(getRandom(), 1, 5);
+        int numNodes = RandomNumbers.randomIntBetween(getRandom(), 1, 5);
         HttpHost[] hosts = new HttpHost[numNodes];
         for (int i = 0; i < numNodes; i++) {
             hosts[i] = new HttpHost("localhost", 9200 + i);
@@ -46,14 +46,14 @@ public class SnifferBuilderTests extends RestClientTestCase {
             }
 
             try {
-                Sniffer.builder(client).setSniffIntervalMillis(RandomInts.randomIntBetween(getRandom(), Integer.MIN_VALUE, 0));
+                Sniffer.builder(client).setSniffIntervalMillis(RandomNumbers.randomIntBetween(getRandom(), Integer.MIN_VALUE, 0));
                 fail("should have failed");
             } catch(IllegalArgumentException e) {
                 assertEquals("sniffIntervalMillis must be greater than 0", e.getMessage());
             }
 
             try {
-                Sniffer.builder(client).setSniffAfterFailureDelayMillis(RandomInts.randomIntBetween(getRandom(), Integer.MIN_VALUE, 0));
+                Sniffer.builder(client).setSniffAfterFailureDelayMillis(RandomNumbers.randomIntBetween(getRandom(), Integer.MIN_VALUE, 0));
                 fail("should have failed");
             } catch(IllegalArgumentException e) {
                 assertEquals("sniffAfterFailureDelayMillis must be greater than 0", e.getMessage());
@@ -74,10 +74,10 @@ public class SnifferBuilderTests extends RestClientTestCase {
 
             SnifferBuilder builder = Sniffer.builder(client);
             if (getRandom().nextBoolean()) {
-                builder.setSniffIntervalMillis(RandomInts.randomIntBetween(getRandom(), 1, Integer.MAX_VALUE));
+                builder.setSniffIntervalMillis(RandomNumbers.randomIntBetween(getRandom(), 1, Integer.MAX_VALUE));
             }
             if (getRandom().nextBoolean()) {
-                builder.setSniffAfterFailureDelayMillis(RandomInts.randomIntBetween(getRandom(), 1, Integer.MAX_VALUE));
+                builder.setSniffAfterFailureDelayMillis(RandomNumbers.randomIntBetween(getRandom(), 1, Integer.MAX_VALUE));
             }
             if (getRandom().nextBoolean()) {
                 builder.setHostsSniffer(new MockHostsSniffer());

core/src/main/java/org/apache/lucene/queryparser/classic/MapperQueryParser.java

@@ -24,6 +24,7 @@ import org.apache.lucene.analysis.TokenStream;
 import org.apache.lucene.analysis.tokenattributes.CharTermAttribute;
 import org.apache.lucene.analysis.tokenattributes.PositionIncrementAttribute;
 import org.apache.lucene.index.Term;
+import org.apache.lucene.queryparser.analyzing.AnalyzingQueryParser;
 import org.apache.lucene.search.BooleanClause;
 import org.apache.lucene.search.BooleanQuery;
 import org.apache.lucene.search.BoostQuery;
@@ -34,6 +35,7 @@ import org.apache.lucene.search.MultiPhraseQuery;
 import org.apache.lucene.search.PhraseQuery;
 import org.apache.lucene.search.Query;
 import org.apache.lucene.search.SynonymQuery;
+import org.apache.lucene.util.BytesRef;
 import org.apache.lucene.util.IOUtils;
 import org.apache.lucene.util.automaton.RegExp;
 import org.elasticsearch.common.lucene.search.Queries;
@@ -42,6 +44,7 @@ import org.elasticsearch.index.mapper.DateFieldMapper;
 import org.elasticsearch.index.mapper.LegacyDateFieldMapper;
 import org.elasticsearch.index.mapper.MappedFieldType;
 import org.elasticsearch.index.mapper.MapperService;
+import org.elasticsearch.index.mapper.StringFieldType;
 import org.elasticsearch.index.query.QueryShardContext;
 import org.elasticsearch.index.query.support.QueryParsers;
 
@@ -63,7 +66,7 @@ import static org.elasticsearch.common.lucene.search.Queries.fixNegativeQueryIfN
  * Also breaks fields with [type].[name] into a boolean query that must include the type
  * as well as the query on the name.
  */
-public class MapperQueryParser extends QueryParser {
+public class MapperQueryParser extends AnalyzingQueryParser {
 
     public static final Map<String, FieldQueryExtension> FIELD_QUERY_EXTENSIONS;
 
@@ -99,11 +102,11 @@ public class MapperQueryParser extends QueryParser {
         setAutoGeneratePhraseQueries(settings.autoGeneratePhraseQueries());
         setMaxDeterminizedStates(settings.maxDeterminizedStates());
         setAllowLeadingWildcard(settings.allowLeadingWildcard());
-        setLowercaseExpandedTerms(settings.lowercaseExpandedTerms());
+        setLowercaseExpandedTerms(false);
         setPhraseSlop(settings.phraseSlop());
         setDefaultOperator(settings.defaultOperator());
         setFuzzyPrefixLength(settings.fuzzyPrefixLength());
-        setLocale(settings.locale());
+        setSplitOnWhitespace(settings.splitOnWhitespace());
     }
 
     /**
@@ -329,21 +332,20 @@ public class MapperQueryParser extends QueryParser {
             boolean startInclusive, boolean endInclusive, QueryShardContext context) {
         currentFieldType = context.fieldMapper(field);
         if (currentFieldType != null) {
-            if (lowercaseExpandedTerms && currentFieldType.tokenized()) {
-                part1 = part1 == null ? null : part1.toLowerCase(locale);
-                part2 = part2 == null ? null : part2.toLowerCase(locale);
-            }
-
             try {
+                BytesRef part1Binary = part1 == null ? null : getAnalyzer().normalize(field, part1);
+                BytesRef part2Binary = part2 == null ? null : getAnalyzer().normalize(field, part2);
                 Query rangeQuery;
                 if (currentFieldType instanceof LegacyDateFieldMapper.DateFieldType && settings.timeZone() != null) {
                     LegacyDateFieldMapper.DateFieldType dateFieldType = (LegacyDateFieldMapper.DateFieldType) this.currentFieldType;
-                    rangeQuery = dateFieldType.rangeQuery(part1, part2, startInclusive, endInclusive, settings.timeZone(), null, context);
+                    rangeQuery = dateFieldType.rangeQuery(part1Binary, part2Binary,
+                            startInclusive, endInclusive, settings.timeZone(), null, context);
                 } else if (currentFieldType instanceof DateFieldMapper.DateFieldType && settings.timeZone() != null) {
                     DateFieldMapper.DateFieldType dateFieldType = (DateFieldMapper.DateFieldType) this.currentFieldType;
-                    rangeQuery = dateFieldType.rangeQuery(part1, part2, startInclusive, endInclusive, settings.timeZone(), null, context);
+                    rangeQuery = dateFieldType.rangeQuery(part1Binary, part2Binary,
+                            startInclusive, endInclusive, settings.timeZone(), null, context);
                 } else {
-                    rangeQuery = currentFieldType.rangeQuery(part1, part2, startInclusive, endInclusive, context);
+                    rangeQuery = currentFieldType.rangeQuery(part1Binary, part2Binary, startInclusive, endInclusive, context);
                 }
                 return rangeQuery;
             } catch (RuntimeException e) {
@@ -357,9 +359,6 @@ public class MapperQueryParser extends QueryParser {
     }
 
     protected Query getFuzzyQuery(String field, String termStr, String minSimilarity) throws ParseException {
-        if (lowercaseExpandedTerms) {
-            termStr = termStr.toLowerCase(locale);
-        }
         Collection<String> fields = extractMultiFields(field);
         if (fields != null) {
             if (fields.size() == 1) {
@@ -398,8 +397,9 @@ public class MapperQueryParser extends QueryParser {
         currentFieldType = context.fieldMapper(field);
         if (currentFieldType != null) {
             try {
-                return currentFieldType.fuzzyQuery(termStr, Fuzziness.build(minSimilarity),
-                    fuzzyPrefixLength, settings.fuzzyMaxExpansions(), FuzzyQuery.defaultTranspositions);
+                BytesRef term = termStr == null ? null : getAnalyzer().normalize(field, termStr);
+                return currentFieldType.fuzzyQuery(term, Fuzziness.build(minSimilarity),
+                    getFuzzyPrefixLength(), settings.fuzzyMaxExpansions(), FuzzyQuery.defaultTranspositions);
             } catch (RuntimeException e) {
                 if (settings.lenient()) {
                     return null;
@@ -422,9 +422,6 @@ public class MapperQueryParser extends QueryParser {
 
     @Override
     protected Query getPrefixQuery(String field, String termStr) throws ParseException {
-        if (lowercaseExpandedTerms) {
-            termStr = termStr.toLowerCase(locale);
-        }
         Collection<String> fields = extractMultiFields(field);
         if (fields != null) {
             if (fields.size() == 1) {
@@ -470,8 +467,8 @@ public class MapperQueryParser extends QueryParser {
                     setAnalyzer(context.getSearchAnalyzer(currentFieldType));
                 }
                 Query query = null;
-                if (currentFieldType.tokenized() == false) {
-                    query = currentFieldType.prefixQuery(termStr, multiTermRewriteMethod, context);
+                if (currentFieldType instanceof StringFieldType == false) {
+                    query = currentFieldType.prefixQuery(termStr, getMultiTermRewriteMethod(), context);
                 }
                 if (query == null) {
                     query = getPossiblyAnalyzedPrefixQuery(currentFieldType.name(), termStr);
@@ -589,9 +586,6 @@ public class MapperQueryParser extends QueryParser {
                 return FIELD_QUERY_EXTENSIONS.get(ExistsFieldQueryExtension.NAME).query(context, actualField);
             }
         }
-        if (lowercaseExpandedTerms) {
-            termStr = termStr.toLowerCase(locale);
-        }
         Collection<String> fields = extractMultiFields(field);
         if (fields != null) {
             if (fields.size() == 1) {
@@ -638,9 +632,8 @@ public class MapperQueryParser extends QueryParser {
                     setAnalyzer(context.getSearchAnalyzer(currentFieldType));
                 }
                 indexedNameField = currentFieldType.name();
-                return getPossiblyAnalyzedWildcardQuery(indexedNameField, termStr);
             }
-            return getPossiblyAnalyzedWildcardQuery(indexedNameField, termStr);
+            return super.getWildcardQuery(indexedNameField, termStr);
         } catch (RuntimeException e) {
             if (settings.lenient()) {
                 return null;
@@ -651,75 +644,8 @@ public class MapperQueryParser extends QueryParser {
         }
     }
 
-    private Query getPossiblyAnalyzedWildcardQuery(String field, String termStr) throws ParseException {
-        if (!settings.analyzeWildcard()) {
-            return super.getWildcardQuery(field, termStr);
-        }
-        boolean isWithinToken = (!termStr.startsWith("?") && !termStr.startsWith("*"));
-        StringBuilder aggStr = new StringBuilder();
-        StringBuilder tmp = new StringBuilder();
-        for (int i = 0; i < termStr.length(); i++) {
-            char c = termStr.charAt(i);
-            if (c == '?' || c == '*') {
-                if (isWithinToken) {
-                    try (TokenStream source = getAnalyzer().tokenStream(field, tmp.toString())) {
-                        source.reset();
-                        CharTermAttribute termAtt = source.addAttribute(CharTermAttribute.class);
-                        if (source.incrementToken()) {
-                            String term = termAtt.toString();
-                            if (term.length() == 0) {
-                                // no tokens, just use what we have now
-                                aggStr.append(tmp);
-                            } else {
-                                aggStr.append(term);
-                            }
-                        } else {
-                            // no tokens, just use what we have now
-                            aggStr.append(tmp);
-                        }
-                    } catch (IOException e) {
-                        aggStr.append(tmp);
-                    }
-                    tmp.setLength(0);
-                }
-                isWithinToken = false;
-                aggStr.append(c);
-            } else {
-                tmp.append(c);
-                isWithinToken = true;
-            }
-        }
-        if (isWithinToken) {
-            try {
-                try (TokenStream source = getAnalyzer().tokenStream(field, tmp.toString())) {
-                    source.reset();
-                    CharTermAttribute termAtt = source.addAttribute(CharTermAttribute.class);
-                    if (source.incrementToken()) {
-                        String term = termAtt.toString();
-                        if (term.length() == 0) {
-                            // no tokens, just use what we have now
-                            aggStr.append(tmp);
-                        } else {
-                            aggStr.append(term);
-                        }
-                    } else {
-                        // no tokens, just use what we have now
-                        aggStr.append(tmp);
-                    }
-                }
-            } catch (IOException e) {
-                aggStr.append(tmp);
-            }
-        }
-
-        return super.getWildcardQuery(field, aggStr.toString());
-    }
-
     @Override
     protected Query getRegexpQuery(String field, String termStr) throws ParseException {
-        if (lowercaseExpandedTerms) {
-            termStr = termStr.toLowerCase(locale);
-        }
         Collection<String> fields = extractMultiFields(field);
         if (fields != null) {
             if (fields.size() == 1) {
@@ -767,7 +693,7 @@ public class MapperQueryParser extends QueryParser {
                 Query query = null;
                 if (currentFieldType.tokenized() == false) {
                     query = currentFieldType.regexpQuery(termStr, RegExp.ALL,
-                        maxDeterminizedStates, multiTermRewriteMethod, context);
+                        getMaxDeterminizedStates(), getMultiTermRewriteMethod(), context);
                 }
                 if (query == null) {
                     query = super.getRegexpQuery(field, termStr);

core/src/main/java/org/apache/lucene/queryparser/classic/QueryParserSettings.java

@@ -24,7 +24,6 @@ import org.apache.lucene.search.MultiTermQuery;
 import org.elasticsearch.common.unit.Fuzziness;
 import org.joda.time.DateTimeZone;
 
-import java.util.Locale;
 import java.util.Map;
 
 /**
@@ -53,12 +52,8 @@ public class QueryParserSettings {
 
     private boolean analyzeWildcard;
 
-    private boolean lowercaseExpandedTerms;
-
     private boolean enablePositionIncrements;
 
-    private Locale locale;
-
     private Fuzziness fuzziness;
     private int fuzzyPrefixLength;
     private int fuzzyMaxExpansions;
@@ -79,6 +74,8 @@ public class QueryParserSettings {
     /** To limit effort spent determinizing regexp queries. */
     private int maxDeterminizedStates;
 
+    private boolean splitOnWhitespace;
+
     public QueryParserSettings(String queryString) {
         this.queryString = queryString;
     }
@@ -135,14 +132,6 @@ public class QueryParserSettings {
         this.allowLeadingWildcard = allowLeadingWildcard;
     }
 
-    public boolean lowercaseExpandedTerms() {
-        return lowercaseExpandedTerms;
-    }
-
-    public void lowercaseExpandedTerms(boolean lowercaseExpandedTerms) {
-        this.lowercaseExpandedTerms = lowercaseExpandedTerms;
-    }
-
     public boolean enablePositionIncrements() {
         return enablePositionIncrements;
     }
@@ -267,14 +256,6 @@ public class QueryParserSettings {
         this.useDisMax = useDisMax;
     }
 
-    public void locale(Locale locale) {
-        this.locale = locale;
-    }
-
-    public Locale locale() {
-        return this.locale;
-    }
-
     public void timeZone(DateTimeZone timeZone) {
         this.timeZone = timeZone;
     }
@@ -290,4 +271,12 @@ public class QueryParserSettings {
     public Fuzziness fuzziness() {
         return fuzziness;
     }
+
+    public void splitOnWhitespace(boolean value) {
+        this.splitOnWhitespace = value;
+    }
+
+    public boolean splitOnWhitespace() {
+        return splitOnWhitespace;
+    }
 }

core/src/main/java/org/elasticsearch/ElasticsearchException.java

@@ -19,7 +19,6 @@
 
 package org.elasticsearch;
 
-import org.apache.logging.log4j.message.ParameterizedMessage;
 import org.elasticsearch.action.support.replication.ReplicationOperation;
 import org.elasticsearch.cluster.action.shard.ShardStateAction;
 import org.elasticsearch.common.io.stream.StreamInput;
@@ -488,7 +487,7 @@ public class ElasticsearchException extends RuntimeException implements ToXConte
         SNAPSHOT_CREATION_EXCEPTION(org.elasticsearch.snapshots.SnapshotCreationException.class,
                 org.elasticsearch.snapshots.SnapshotCreationException::new, 27),
         DELETE_FAILED_ENGINE_EXCEPTION(org.elasticsearch.index.engine.DeleteFailedEngineException.class,
-                org.elasticsearch.index.engine.DeleteFailedEngineException::new, 28),
+                org.elasticsearch.index.engine.DeleteFailedEngineException::new, 28),// deprecated in 6.0, remove in 7.0
         DOCUMENT_MISSING_EXCEPTION(org.elasticsearch.index.engine.DocumentMissingException.class,
                 org.elasticsearch.index.engine.DocumentMissingException::new, 29),
         SNAPSHOT_EXCEPTION(org.elasticsearch.snapshots.SnapshotException.class,
@@ -582,7 +581,7 @@ public class ElasticsearchException extends RuntimeException implements ToXConte
         ROUTING_MISSING_EXCEPTION(org.elasticsearch.action.RoutingMissingException.class,
                 org.elasticsearch.action.RoutingMissingException::new, 79),
         INDEX_FAILED_ENGINE_EXCEPTION(org.elasticsearch.index.engine.IndexFailedEngineException.class,
-                org.elasticsearch.index.engine.IndexFailedEngineException::new, 80),
+                org.elasticsearch.index.engine.IndexFailedEngineException::new, 80), // deprecated in 6.0, remove in 7.0
         INDEX_SHARD_RESTORE_FAILED_EXCEPTION(org.elasticsearch.index.snapshots.IndexShardRestoreFailedException.class,
                 org.elasticsearch.index.snapshots.IndexShardRestoreFailedException::new, 81),
         REPOSITORY_EXCEPTION(org.elasticsearch.repositories.RepositoryException.class,

core/src/main/java/org/elasticsearch/Version.java

@@ -89,8 +89,10 @@ public class Version {
     public static final Version V_5_0_0_beta1 = new Version(V_5_0_0_beta1_ID, org.apache.lucene.util.Version.LUCENE_6_2_0);
     public static final int V_5_0_0_rc1_ID = 5000051;
     public static final Version V_5_0_0_rc1 = new Version(V_5_0_0_rc1_ID, org.apache.lucene.util.Version.LUCENE_6_2_0);
+    public static final int V_5_0_0_ID = 5000099;
+    public static final Version V_5_0_0 = new Version(V_5_0_0_ID, org.apache.lucene.util.Version.LUCENE_6_2_0);
     public static final int V_6_0_0_alpha1_ID = 6000001;
-    public static final Version V_6_0_0_alpha1 = new Version(V_6_0_0_alpha1_ID, org.apache.lucene.util.Version.LUCENE_6_2_0);
+    public static final Version V_6_0_0_alpha1 = new Version(V_6_0_0_alpha1_ID, org.apache.lucene.util.Version.LUCENE_6_3_0);
     public static final Version CURRENT = V_6_0_0_alpha1;
 
     /* NOTE: don't add unreleased version to this list except of the version assigned to CURRENT.
@@ -115,6 +117,8 @@ public class Version {
         switch (id) {
             case V_6_0_0_alpha1_ID:
                 return V_6_0_0_alpha1;
+            case V_5_0_0_ID:
+                return V_5_0_0;
             case V_5_0_0_rc1_ID:
                 return V_5_0_0_rc1;
             case V_5_0_0_beta1_ID:

core/src/main/java/org/elasticsearch/action/admin/cluster/tasks/PendingClusterTasksResponse.java

@@ -25,7 +25,6 @@ import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.xcontent.ToXContent;
 import org.elasticsearch.common.xcontent.XContentBuilder;
-import org.elasticsearch.common.xcontent.XContentFactory;
 
 import java.io.IOException;
 import java.util.ArrayList;
@@ -59,7 +58,8 @@ public class PendingClusterTasksResponse extends ActionResponse implements Itera
         return pendingTasks.iterator();
     }
 
-    public String prettyPrint() {
+    @Override
+    public String toString() {
         StringBuilder sb = new StringBuilder();
         sb.append("tasks: (").append(pendingTasks.size()).append("):\n");
         for (PendingClusterTask pendingClusterTask : this) {
@@ -68,19 +68,6 @@ public class PendingClusterTasksResponse extends ActionResponse implements Itera
         return sb.toString();
     }
 
-    @Override
-    public String toString() {
-        try {
-            XContentBuilder builder = XContentFactory.jsonBuilder().prettyPrint();
-            builder.startObject();
-            toXContent(builder, EMPTY_PARAMS);
-            builder.endObject();
-            return builder.string();
-        } catch (IOException e) {
-            return "{ \"error\" : \"" + e.getMessage() + "\"}";
-        }
-    }
-
     @Override
     public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
         builder.startArray(Fields.TASKS);

core/src/main/java/org/elasticsearch/action/bulk/TransportShardBulkAction.java

@@ -21,19 +21,15 @@ package org.elasticsearch.action.bulk;
 
 import org.apache.logging.log4j.message.ParameterizedMessage;
 import org.apache.logging.log4j.util.Supplier;
-import org.elasticsearch.ElasticsearchException;
-import org.elasticsearch.ExceptionsHelper;
-import org.elasticsearch.action.DocWriteResponse;
 import org.elasticsearch.action.DocWriteRequest;
+import org.elasticsearch.action.DocWriteResponse;
 import org.elasticsearch.action.delete.DeleteRequest;
 import org.elasticsearch.action.delete.DeleteResponse;
-import org.elasticsearch.action.delete.TransportDeleteAction;
 import org.elasticsearch.action.index.IndexRequest;
 import org.elasticsearch.action.index.IndexResponse;
-import org.elasticsearch.action.index.TransportIndexAction;
 import org.elasticsearch.action.support.ActionFilters;
-import org.elasticsearch.action.support.replication.TransportWriteAction;
 import org.elasticsearch.action.support.replication.ReplicationResponse.ShardInfo;
+import org.elasticsearch.action.support.replication.TransportWriteAction;
 import org.elasticsearch.action.update.UpdateHelper;
 import org.elasticsearch.action.update.UpdateRequest;
 import org.elasticsearch.action.update.UpdateResponse;
@@ -51,10 +47,12 @@ import org.elasticsearch.common.xcontent.XContentHelper;
 import org.elasticsearch.common.xcontent.XContentType;
 import org.elasticsearch.index.VersionType;
 import org.elasticsearch.index.engine.Engine;
+import org.elasticsearch.index.engine.EngineClosedException;
 import org.elasticsearch.index.engine.VersionConflictEngineException;
+import org.elasticsearch.index.mapper.MapperParsingException;
 import org.elasticsearch.index.shard.IndexShard;
+import org.elasticsearch.index.shard.IndexShardClosedException;
 import org.elasticsearch.index.translog.Translog;
-import org.elasticsearch.index.translog.Translog.Location;
 import org.elasticsearch.indices.IndicesService;
 import org.elasticsearch.threadpool.ThreadPool;
 import org.elasticsearch.transport.TransportRequestOptions;
@@ -62,11 +60,15 @@ import org.elasticsearch.transport.TransportService;
 
 import java.util.Map;
 
+import static org.elasticsearch.action.delete.TransportDeleteAction.executeDeleteRequestOnPrimary;
+import static org.elasticsearch.action.delete.TransportDeleteAction.executeDeleteRequestOnReplica;
+import static org.elasticsearch.action.index.TransportIndexAction.executeIndexRequestOnPrimary;
+import static org.elasticsearch.action.index.TransportIndexAction.executeIndexRequestOnReplica;
 import static org.elasticsearch.action.support.replication.ReplicationOperation.ignoreReplicaException;
 import static org.elasticsearch.action.support.replication.ReplicationOperation.isConflictException;
 
 /** Performs shard-level bulk (index, delete or update) operations */
-public class TransportShardBulkAction extends TransportWriteAction<BulkShardRequest, BulkShardResponse> {
+public class TransportShardBulkAction extends TransportWriteAction<BulkShardRequest, BulkShardRequest, BulkShardResponse> {
 
     public static final String ACTION_NAME = BulkAction.NAME + "[s]";
 
@@ -80,7 +82,7 @@ public class TransportShardBulkAction extends TransportWriteAction<BulkShardRequ
                                     MappingUpdatedAction mappingUpdatedAction, UpdateHelper updateHelper, ActionFilters actionFilters,
                                     IndexNameExpressionResolver indexNameExpressionResolver) {
         super(settings, ACTION_NAME, transportService, clusterService, indicesService, threadPool, shardStateAction, actionFilters,
-                indexNameExpressionResolver, BulkShardRequest::new, ThreadPool.Names.BULK);
+                indexNameExpressionResolver, BulkShardRequest::new, BulkShardRequest::new, ThreadPool.Names.BULK);
         this.updateHelper = updateHelper;
         this.allowIdGeneration = settings.getAsBoolean("action.allow_id_generation", true);
         this.mappingUpdatedAction = mappingUpdatedAction;
@@ -102,7 +104,7 @@ public class TransportShardBulkAction extends TransportWriteAction<BulkShardRequ
     }
 
     @Override
-    protected WriteResult<BulkShardResponse> onPrimaryShard(BulkShardRequest request, IndexShard primary) throws Exception {
+    protected WritePrimaryResult shardOperationOnPrimary(BulkShardRequest request, IndexShard primary) throws Exception {
         final IndexMetaData metaData = primary.indexSettings().getIndexMetaData();
 
         long[] preVersions = new long[request.items().length];
@@ -118,30 +120,86 @@ public class TransportShardBulkAction extends TransportWriteAction<BulkShardRequ
             responses[i] = items[i].getPrimaryResponse();
         }
         BulkShardResponse response = new BulkShardResponse(request.shardId(), responses);
-        return new WriteResult<>(response, location);
+        return new WritePrimaryResult(request, response, location, null, primary);
     }
 
     /** Executes bulk item requests and handles request execution exceptions */
-    private Translog.Location executeBulkItemRequest(IndexMetaData metaData, IndexShard indexShard,
+    private Translog.Location executeBulkItemRequest(IndexMetaData metaData, IndexShard primary,
                                                      BulkShardRequest request,
                                                      long[] preVersions, VersionType[] preVersionTypes,
-                                                     Translog.Location location, int requestIndex) {
-        preVersions[requestIndex] = request.items()[requestIndex].request().version();
-        preVersionTypes[requestIndex] = request.items()[requestIndex].request().versionType();
-        DocWriteRequest.OpType opType = request.items()[requestIndex].request().opType();
+                                                     Translog.Location location, int requestIndex) throws Exception {
+        final DocWriteRequest itemRequest = request.items()[requestIndex].request();
+        preVersions[requestIndex] = itemRequest.version();
+        preVersionTypes[requestIndex] = itemRequest.versionType();
+        DocWriteRequest.OpType opType = itemRequest.opType();
         try {
-            WriteResult<? extends DocWriteResponse> writeResult = innerExecuteBulkItemRequest(metaData, indexShard,
-                request, requestIndex);
-            if (writeResult.getLocation() != null) {
-                location = locationToSync(location, writeResult.getLocation());
-            } else {
-                assert writeResult.getResponse().getResult() == DocWriteResponse.Result.NOOP
-                        : "only noop operation can have null next operation";
+            // execute item request
+            final Engine.Result operationResult;
+            final DocWriteResponse response;
+            final BulkItemRequest replicaRequest;
+            switch (itemRequest.opType()) {
+                case CREATE:
+                case INDEX:
+                    final IndexRequest indexRequest = (IndexRequest) itemRequest;
+                    Engine.IndexResult indexResult = executeIndexRequestOnPrimary(indexRequest, primary, mappingUpdatedAction);
+                    operationResult = indexResult;
+                    response = indexResult.hasFailure() ? null
+                            : new IndexResponse(primary.shardId(), indexRequest.type(), indexRequest.id(),
+                                indexResult.getVersion(), indexResult.isCreated());
+                    replicaRequest = request.items()[requestIndex];
+                    break;
+                case UPDATE:
+                    UpdateResultHolder updateResultHolder = executeUpdateRequest(((UpdateRequest) itemRequest),
+                            primary, metaData, request, requestIndex);
+                    operationResult = updateResultHolder.operationResult;
+                    response = updateResultHolder.response;
+                    replicaRequest = updateResultHolder.replicaRequest;
+                    break;
+                case DELETE:
+                    final DeleteRequest deleteRequest = (DeleteRequest) itemRequest;
+                    Engine.DeleteResult deleteResult = executeDeleteRequestOnPrimary(deleteRequest, primary);
+                    operationResult = deleteResult;
+                    response = deleteResult.hasFailure() ? null :
+                            new DeleteResponse(request.shardId(), deleteRequest.type(), deleteRequest.id(),
+                                deleteResult.getVersion(), deleteResult.isFound());
+                    replicaRequest = request.items()[requestIndex];
+                    break;
+                default: throw new IllegalStateException("unexpected opType [" + itemRequest.opType() + "] found");
             }
             // update the bulk item request because update request execution can mutate the bulk item request
-            BulkItemRequest item = request.items()[requestIndex];
-            // add the response
-            setResponse(item, new BulkItemResponse(item.id(), opType, writeResult.getResponse()));
+            request.items()[requestIndex] = replicaRequest;
+            if (operationResult == null) { // in case of noop update operation
+                assert response.getResult() == DocWriteResponse.Result.NOOP
+                        : "only noop update can have null operation";
+                replicaRequest.setIgnoreOnReplica();
+                replicaRequest.setPrimaryResponse(new BulkItemResponse(replicaRequest.id(), opType, response));
+            } else if (operationResult.hasFailure() == false) {
+                location = locationToSync(location, operationResult.getTranslogLocation());
+                BulkItemResponse primaryResponse = new BulkItemResponse(replicaRequest.id(), opType, response);
+                replicaRequest.setPrimaryResponse(primaryResponse);
+                // set the ShardInfo to 0 so we can safely send it to the replicas. We won't use it in the real response though.
+                primaryResponse.getResponse().setShardInfo(new ShardInfo());
+            } else {
+                DocWriteRequest docWriteRequest = replicaRequest.request();
+                Exception failure = operationResult.getFailure();
+                if (isConflictException(failure)) {
+                    logger.trace((Supplier<?>) () -> new ParameterizedMessage("{} failed to execute bulk item ({}) {}",
+                            request.shardId(), docWriteRequest.opType().getLowercase(), request), failure);
+                } else {
+                    logger.debug((Supplier<?>) () -> new ParameterizedMessage("{} failed to execute bulk item ({}) {}",
+                            request.shardId(), docWriteRequest.opType().getLowercase(), request), failure);
+                }
+                // if its a conflict failure, and we already executed the request on a primary (and we execute it
+                // again, due to primary relocation and only processing up to N bulk items when the shard gets closed)
+                // then just use the response we got from the successful execution
+                if (replicaRequest.getPrimaryResponse() == null || isConflictException(failure) == false) {
+                    replicaRequest.setIgnoreOnReplica();
+                    replicaRequest.setPrimaryResponse(new BulkItemResponse(replicaRequest.id(), docWriteRequest.opType(),
+                            new BulkItemResponse.Failure(request.index(), docWriteRequest.type(), docWriteRequest.id(), failure)));
+                }
+            }
+            assert replicaRequest.getPrimaryResponse() != null;
+            assert preVersionTypes[requestIndex] != null;
         } catch (Exception e) {
             // rethrow the failure if we are going to retry on primary and let parent failure to handle it
             if (retryPrimaryException(e)) {
@@ -151,147 +209,165 @@ public class TransportShardBulkAction extends TransportWriteAction<BulkShardRequ
                     docWriteRequest.version(preVersions[j]);
                     docWriteRequest.versionType(preVersionTypes[j]);
                 }
-                throw (ElasticsearchException) e;
-            }
-            BulkItemRequest item = request.items()[requestIndex];
-            DocWriteRequest docWriteRequest = item.request();
-            if (isConflictException(e)) {
-                logger.trace((Supplier<?>) () -> new ParameterizedMessage("{} failed to execute bulk item ({}) {}",
-                        request.shardId(), docWriteRequest.opType().getLowercase(), request), e);
-            } else {
-                logger.debug((Supplier<?>) () -> new ParameterizedMessage("{} failed to execute bulk item ({}) {}",
-                        request.shardId(), docWriteRequest.opType().getLowercase(), request), e);
-            }
-            // if its a conflict failure, and we already executed the request on a primary (and we execute it
-            // again, due to primary relocation and only processing up to N bulk items when the shard gets closed)
-            // then just use the response we got from the successful execution
-            if (item.getPrimaryResponse() != null && isConflictException(e)) {
-                setResponse(item, item.getPrimaryResponse());
-            } else {
-                setResponse(item, new BulkItemResponse(item.id(), docWriteRequest.opType(),
-                    new BulkItemResponse.Failure(request.index(), docWriteRequest.type(), docWriteRequest.id(), e)));
             }
+            throw e;
         }
-        assert request.items()[requestIndex].getPrimaryResponse() != null;
-        assert preVersionTypes[requestIndex] != null;
         return location;
     }
 
-    private WriteResult<? extends DocWriteResponse> innerExecuteBulkItemRequest(IndexMetaData metaData, IndexShard indexShard,
-                                                            BulkShardRequest request, int requestIndex) throws Exception {
-        DocWriteRequest itemRequest = request.items()[requestIndex].request();
-        switch (itemRequest.opType()) {
-            case CREATE:
-            case INDEX:
-                return TransportIndexAction.executeIndexRequestOnPrimary(((IndexRequest) itemRequest), indexShard, mappingUpdatedAction);
-            case UPDATE:
-                int maxAttempts = ((UpdateRequest) itemRequest).retryOnConflict();
-                for (int attemptCount = 0; attemptCount <= maxAttempts; attemptCount++) {
-                    try {
-                        return shardUpdateOperation(metaData, indexShard, request, requestIndex, ((UpdateRequest) itemRequest));
-                    } catch (Exception e) {
-                        final Throwable cause = ExceptionsHelper.unwrapCause(e);
-                        if (attemptCount == maxAttempts  // bubble up exception when we run out of attempts
-                                || (cause instanceof VersionConflictEngineException) == false) { // or when exception is not a version conflict
-                            throw e;
-                        }
-                    }
-                }
-                throw new IllegalStateException("version conflict exception should bubble up on last attempt");
-            case DELETE:
-                return TransportDeleteAction.executeDeleteRequestOnPrimary(((DeleteRequest) itemRequest), indexShard);
-            default: throw new IllegalStateException("unexpected opType [" + itemRequest.opType() + "] found");
-        }
-    }
+    private static class UpdateResultHolder {
+        final BulkItemRequest replicaRequest;
+        final Engine.Result operationResult;
+        final DocWriteResponse response;
 
-    private void setResponse(BulkItemRequest request, BulkItemResponse response) {
-        request.setPrimaryResponse(response);
-        if (response.isFailed()) {
-            request.setIgnoreOnReplica();
-        } else {
-            // Set the ShardInfo to 0 so we can safely send it to the replicas. We won't use it in the real response though.
-            response.getResponse().setShardInfo(new ShardInfo());
+        private UpdateResultHolder(BulkItemRequest replicaRequest, Engine.Result operationResult,
+                                   DocWriteResponse response) {
+            this.replicaRequest = replicaRequest;
+            this.operationResult = operationResult;
+            this.response = response;
         }
     }
 
     /**
-     * Executes update request, doing a get and translating update to a index or delete operation
-     * NOTE: all operations except NOOP, reassigns the bulk item request
-     */
-    private WriteResult<? extends DocWriteResponse> shardUpdateOperation(IndexMetaData metaData, IndexShard indexShard,
-                                                                         BulkShardRequest request,
-                                                                         int requestIndex, UpdateRequest updateRequest)
-        throws Exception {
-        // Todo: capture read version conflicts, missing documents and malformed script errors in the write result due to get request
-        UpdateHelper.Result translate = updateHelper.prepare(updateRequest, indexShard, threadPool::estimatedTimeInMillis);
-        switch (translate.getResponseResult()) {
-            case CREATED:
-            case UPDATED:
-                IndexRequest indexRequest = translate.action();
-                MappingMetaData mappingMd = metaData.mappingOrDefault(indexRequest.type());
-                indexRequest.process(mappingMd, allowIdGeneration, request.index());
-                WriteResult<IndexResponse> writeResult = TransportIndexAction.executeIndexRequestOnPrimary(indexRequest, indexShard, mappingUpdatedAction);
-                BytesReference indexSourceAsBytes = indexRequest.source();
-                IndexResponse indexResponse = writeResult.getResponse();
-                UpdateResponse update = new UpdateResponse(indexResponse.getShardInfo(), indexResponse.getShardId(), indexResponse.getType(), indexResponse.getId(), indexResponse.getVersion(), indexResponse.getResult());
-                if ((updateRequest.fetchSource() != null && updateRequest.fetchSource().fetchSource()) ||
-                        (updateRequest.fields() != null && updateRequest.fields().length > 0)) {
-                    Tuple<XContentType, Map<String, Object>> sourceAndContent = XContentHelper.convertToMap(indexSourceAsBytes, true);
-                    update.setGetResult(updateHelper.extractGetResult(updateRequest, request.index(), indexResponse.getVersion(), sourceAndContent.v2(), sourceAndContent.v1(), indexSourceAsBytes));
+     * Executes update request, delegating to a index or delete operation after translation,
+     * handles retries on version conflict and constructs update response
+     * NOTE: reassigns bulk item request at <code>requestIndex</code> for replicas to
+     * execute translated update request (NOOP update is an exception). NOOP updates are
+     * indicated by returning a <code>null</code> operation in {@link UpdateResultHolder}
+     * */
+    private UpdateResultHolder executeUpdateRequest(UpdateRequest updateRequest, IndexShard primary,
+                                                    IndexMetaData metaData, BulkShardRequest request,
+                                                    int requestIndex) throws Exception {
+        Engine.Result updateOperationResult = null;
+        UpdateResponse updateResponse = null;
+        BulkItemRequest replicaRequest = request.items()[requestIndex];
+        int maxAttempts = updateRequest.retryOnConflict();
+        for (int attemptCount = 0; attemptCount <= maxAttempts; attemptCount++) {
+            final UpdateHelper.Result translate;
+            // translate update request
+            try {
+                translate = updateHelper.prepare(updateRequest, primary, threadPool::estimatedTimeInMillis);
+            } catch (Exception failure) {
+                // we may fail translating a update to index or delete operation
+                // we use index result to communicate failure while translating update request
+                updateOperationResult = new Engine.IndexResult(failure, updateRequest.version());
+                break; // out of retry loop
+            }
+            // execute translated update request
+            switch (translate.getResponseResult()) {
+                case CREATED:
+                case UPDATED:
+                    IndexRequest indexRequest = translate.action();
+                    MappingMetaData mappingMd = metaData.mappingOrDefault(indexRequest.type());
+                    indexRequest.process(mappingMd, allowIdGeneration, request.index());
+                    updateOperationResult = executeIndexRequestOnPrimary(indexRequest, primary, mappingUpdatedAction);
+                    break;
+                case DELETED:
+                    updateOperationResult = executeDeleteRequestOnPrimary(translate.action(), primary);
+                    break;
+                case NOOP:
+                    primary.noopUpdate(updateRequest.type());
+                    break;
+                default: throw new IllegalStateException("Illegal update operation " + translate.getResponseResult());
+            }
+            if (updateOperationResult == null) {
+                // this is a noop operation
+                updateResponse = translate.action();
+                break; // out of retry loop
+            } else if (updateOperationResult.hasFailure() == false) {
+                // enrich update response and
+                // set translated update (index/delete) request for replica execution in bulk items
+                switch (updateOperationResult.getOperationType()) {
+                    case INDEX:
+                        IndexRequest updateIndexRequest = translate.action();
+                        final IndexResponse indexResponse = new IndexResponse(primary.shardId(),
+                                updateIndexRequest.type(), updateIndexRequest.id(),
+                                updateOperationResult.getVersion(), ((Engine.IndexResult) updateOperationResult).isCreated());
+                        BytesReference indexSourceAsBytes = updateIndexRequest.source();
+                        updateResponse = new UpdateResponse(indexResponse.getShardInfo(),
+                                indexResponse.getShardId(), indexResponse.getType(), indexResponse.getId(),
+                                indexResponse.getVersion(), indexResponse.getResult());
+                        if ((updateRequest.fetchSource() != null && updateRequest.fetchSource().fetchSource()) ||
+                                (updateRequest.fields() != null && updateRequest.fields().length > 0)) {
+                            Tuple<XContentType, Map<String, Object>> sourceAndContent =
+                                    XContentHelper.convertToMap(indexSourceAsBytes, true);
+                            updateResponse.setGetResult(updateHelper.extractGetResult(updateRequest, request.index(),
+                                    indexResponse.getVersion(), sourceAndContent.v2(), sourceAndContent.v1(), indexSourceAsBytes));
+                        }
+                        // set translated request as replica request
+                        replicaRequest = new BulkItemRequest(request.items()[requestIndex].id(), updateIndexRequest);
+                        break;
+                    case DELETE:
+                        DeleteRequest updateDeleteRequest = translate.action();
+                        DeleteResponse deleteResponse = new DeleteResponse(primary.shardId(),
+                                updateDeleteRequest.type(), updateDeleteRequest.id(),
+                                updateOperationResult.getVersion(), ((Engine.DeleteResult) updateOperationResult).isFound());
+                        updateResponse = new UpdateResponse(deleteResponse.getShardInfo(),
+                                deleteResponse.getShardId(), deleteResponse.getType(), deleteResponse.getId(),
+                                deleteResponse.getVersion(), deleteResponse.getResult());
+                        updateResponse.setGetResult(updateHelper.extractGetResult(updateRequest,
+                                request.index(), deleteResponse.getVersion(), translate.updatedSourceAsMap(),
+                                translate.updateSourceContentType(), null));
+                        // set translated request as replica request
+                        replicaRequest = new BulkItemRequest(request.items()[requestIndex].id(), updateDeleteRequest);
+                        break;
                 }
-                // Replace the update request to the translated index request to execute on the replica.
-                request.items()[requestIndex] = new BulkItemRequest(request.items()[requestIndex].id(), indexRequest);
-                return new WriteResult<>(update, writeResult.getLocation());
-            case DELETED:
-                DeleteRequest deleteRequest = translate.action();
-                WriteResult<DeleteResponse> deleteResult = TransportDeleteAction.executeDeleteRequestOnPrimary(deleteRequest, indexShard);
-                DeleteResponse response = deleteResult.getResponse();
-                UpdateResponse deleteUpdateResponse = new UpdateResponse(response.getShardInfo(), response.getShardId(), response.getType(), response.getId(), response.getVersion(), response.getResult());
-                deleteUpdateResponse.setGetResult(updateHelper.extractGetResult(updateRequest, request.index(), response.getVersion(), translate.updatedSourceAsMap(), translate.updateSourceContentType(), null));
-                // Replace the update request to the translated delete request to execute on the replica.
-                request.items()[requestIndex] = new BulkItemRequest(request.items()[requestIndex].id(), deleteRequest);
-                return new WriteResult<>(deleteUpdateResponse, deleteResult.getLocation());
-            case NOOP:
-                BulkItemRequest item = request.items()[requestIndex];
-                indexShard.noopUpdate(updateRequest.type());
-                item.setIgnoreOnReplica(); // no need to go to the replica
-                return new WriteResult<>(translate.action(), null);
-            default: throw new IllegalStateException("Illegal update operation " + translate.getResponseResult());
+                // successful operation
+                break; // out of retry loop
+            } else if (updateOperationResult.getFailure() instanceof VersionConflictEngineException == false) {
+                // not a version conflict exception
+                break; // out of retry loop
+            }
         }
+        return new UpdateResultHolder(replicaRequest, updateOperationResult, updateResponse);
     }
 
     @Override
-    protected Location onReplicaShard(BulkShardRequest request, IndexShard indexShard) {
+    protected WriteReplicaResult shardOperationOnReplica(BulkShardRequest request, IndexShard replica) throws Exception {
         Translog.Location location = null;
         for (int i = 0; i < request.items().length; i++) {
             BulkItemRequest item = request.items()[i];
-            if (item == null || item.isIgnoreOnReplica()) {
-                continue;
-            }
-            DocWriteRequest docWriteRequest = item.request();
-            final Engine.Operation operation;
-            try {
-                switch (docWriteRequest.opType()) {
-                    case CREATE:
-                    case INDEX:
-                        operation = TransportIndexAction.executeIndexRequestOnReplica(((IndexRequest) docWriteRequest), indexShard);
-                        break;
-                    case DELETE:
-                        operation = TransportDeleteAction.executeDeleteRequestOnReplica(((DeleteRequest) docWriteRequest), indexShard);
-                        break;
-                    default: throw new IllegalStateException("Unexpected request operation type on replica: "
-                            + docWriteRequest.opType().getLowercase());
-                }
-                location = locationToSync(location, operation.getTranslogLocation());
-            } catch (Exception e) {
-                // if its not an ignore replica failure, we need to make sure to bubble up the failure
-                // so we will fail the shard
-                if (!ignoreReplicaException(e)) {
-                    throw e;
+            if (item.isIgnoreOnReplica() == false) {
+                DocWriteRequest docWriteRequest = item.request();
+                final Engine.Result operationResult;
+                try {
+                    switch (docWriteRequest.opType()) {
+                        case CREATE:
+                        case INDEX:
+                            operationResult = executeIndexRequestOnReplica(((IndexRequest) docWriteRequest), replica);
+                            break;
+                        case DELETE:
+                            operationResult = executeDeleteRequestOnReplica(((DeleteRequest) docWriteRequest), replica);
+                            break;
+                        default:
+                            throw new IllegalStateException("Unexpected request operation type on replica: "
+                                    + docWriteRequest.opType().getLowercase());
+                    }
+                    if (operationResult.hasFailure()) {
+                        // check if any transient write operation failures should be bubbled up
+                        Exception failure = operationResult.getFailure();
+                        assert failure instanceof VersionConflictEngineException
+                                || failure instanceof MapperParsingException
+                                || failure instanceof EngineClosedException
+                                || failure instanceof IndexShardClosedException
+                                : "expected any one of [version conflict, mapper parsing, engine closed, index shard closed]" +
+                                " failures. got " + failure;
+                        if (!ignoreReplicaException(failure)) {
+                            throw failure;
+                        }
+                    } else {
+                        location = locationToSync(location, operationResult.getTranslogLocation());
+                    }
+                } catch (Exception e) {
+                    // if its not an ignore replica failure, we need to make sure to bubble up the failure
+                    // so we will fail the shard
+                    if (!ignoreReplicaException(e)) {
+                        throw e;
+                    }
                 }
             }
         }
-        return location;
+        return new WriteReplicaResult(request, location, null, replica);
     }
 
     private Translog.Location locationToSync(Translog.Location current, Translog.Location next) {

core/src/main/java/org/elasticsearch/action/delete/TransportDeleteAction.java

@@ -39,7 +39,6 @@ import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.index.engine.Engine;
 import org.elasticsearch.index.shard.IndexShard;
 import org.elasticsearch.index.shard.ShardId;
-import org.elasticsearch.index.translog.Translog.Location;
 import org.elasticsearch.indices.IndexAlreadyExistsException;
 import org.elasticsearch.indices.IndicesService;
 import org.elasticsearch.tasks.Task;
@@ -49,7 +48,7 @@ import org.elasticsearch.transport.TransportService;
 /**
  * Performs the delete operation.
  */
-public class TransportDeleteAction extends TransportWriteAction<DeleteRequest, DeleteResponse> {
+public class TransportDeleteAction extends TransportWriteAction<DeleteRequest, DeleteRequest,DeleteResponse> {
 
     private final AutoCreateIndex autoCreateIndex;
     private final TransportCreateIndexAction createIndexAction;
@@ -61,7 +60,7 @@ public class TransportDeleteAction extends TransportWriteAction<DeleteRequest, D
                                  IndexNameExpressionResolver indexNameExpressionResolver,
                                  AutoCreateIndex autoCreateIndex) {
         super(settings, DeleteAction.NAME, transportService, clusterService, indicesService, threadPool, shardStateAction, actionFilters,
-                indexNameExpressionResolver, DeleteRequest::new, ThreadPool.Names.INDEX);
+                indexNameExpressionResolver, DeleteRequest::new, DeleteRequest::new, ThreadPool.Names.INDEX);
         this.createIndexAction = createIndexAction;
         this.autoCreateIndex = autoCreateIndex;
     }
@@ -70,7 +69,11 @@ public class TransportDeleteAction extends TransportWriteAction<DeleteRequest, D
     protected void doExecute(Task task, final DeleteRequest request, final ActionListener<DeleteResponse> listener) {
         ClusterState state = clusterService.state();
         if (autoCreateIndex.shouldAutoCreate(request.index(), state)) {
-            createIndexAction.execute(task, new CreateIndexRequest().index(request.index()).cause("auto(delete api)").masterNodeTimeout(request.timeout()), new ActionListener<CreateIndexResponse>() {
+            CreateIndexRequest createIndexRequest = new CreateIndexRequest()
+                    .index(request.index())
+                    .cause("auto(delete api)")
+                    .masterNodeTimeout(request.timeout());
+            createIndexAction.execute(task, createIndexRequest, new ActionListener<CreateIndexResponse>() {
                 @Override
                 public void onResponse(CreateIndexResponse result) {
                     innerExecute(task, request, listener);
@@ -119,30 +122,33 @@ public class TransportDeleteAction extends TransportWriteAction<DeleteRequest, D
     }
 
     @Override
-    protected WriteResult<DeleteResponse> onPrimaryShard(DeleteRequest request, IndexShard indexShard) {
-        return executeDeleteRequestOnPrimary(request, indexShard);
+    protected WritePrimaryResult shardOperationOnPrimary(DeleteRequest request, IndexShard primary) throws Exception {
+        final Engine.DeleteResult result = executeDeleteRequestOnPrimary(request, primary);
+        final DeleteResponse response = result.hasFailure() ? null :
+                new DeleteResponse(primary.shardId(), request.type(), request.id(), result.getVersion(), result.isFound());
+        return new WritePrimaryResult(request, response, result.getTranslogLocation(), result.getFailure(), primary);
     }
 
     @Override
-    protected Location onReplicaShard(DeleteRequest request, IndexShard indexShard) {
-        return executeDeleteRequestOnReplica(request, indexShard).getTranslogLocation();
+    protected WriteReplicaResult shardOperationOnReplica(DeleteRequest request, IndexShard replica) throws Exception {
+        final Engine.DeleteResult result = executeDeleteRequestOnReplica(request, replica);
+        return new WriteReplicaResult(request, result.getTranslogLocation(), result.getFailure(), replica);
     }
 
-    public static WriteResult<DeleteResponse> executeDeleteRequestOnPrimary(DeleteRequest request, IndexShard indexShard) {
-        Engine.Delete delete = indexShard.prepareDeleteOnPrimary(request.type(), request.id(), request.version(), request.versionType());
-        indexShard.delete(delete);
-        // update the request with the version so it will go to the replicas
-        request.versionType(delete.versionType().versionTypeForReplicationAndRecovery());
-        request.version(delete.version());
-
-        assert request.versionType().validateVersionForWrites(request.version());
-        DeleteResponse response = new DeleteResponse(indexShard.shardId(), request.type(), request.id(), delete.version(), delete.found());
-        return new WriteResult<>(response, delete.getTranslogLocation());
+    public static Engine.DeleteResult executeDeleteRequestOnPrimary(DeleteRequest request, IndexShard primary) {
+        Engine.Delete delete = primary.prepareDeleteOnPrimary(request.type(), request.id(), request.version(), request.versionType());
+        Engine.DeleteResult result = primary.delete(delete);
+        if (result.hasFailure() == false) {
+            // update the request with the version so it will go to the replicas
+            request.versionType(delete.versionType().versionTypeForReplicationAndRecovery());
+            request.version(result.getVersion());
+            assert request.versionType().validateVersionForWrites(request.version());
+        }
+        return result;
     }
 
-    public static Engine.Delete executeDeleteRequestOnReplica(DeleteRequest request, IndexShard indexShard) {
-        Engine.Delete delete = indexShard.prepareDeleteOnReplica(request.type(), request.id(), request.version(), request.versionType());
-        indexShard.delete(delete);
-        return delete;
+    public static Engine.DeleteResult executeDeleteRequestOnReplica(DeleteRequest request, IndexShard replica) {
+        Engine.Delete delete = replica.prepareDeleteOnReplica(request.type(), request.id(), request.version(), request.versionType());
+        return replica.delete(delete);
     }
 }

core/src/main/java/org/elasticsearch/action/get/GetRequest.java

@@ -101,6 +101,9 @@ public class GetRequest extends SingleShardRequest<GetRequest> implements Realti
             validationException = ValidateActions.addValidationError("illegal version value [" + version + "] for version type [" + versionType.name() + "]",
                     validationException);
         }
+        if (versionType == VersionType.FORCE) {
+            validationException = ValidateActions.addValidationError("version type [force] may no longer be used", validationException);
+        }
         return validationException;
     }
 

core/src/main/java/org/elasticsearch/action/index/TransportIndexAction.java

@@ -39,11 +39,11 @@ import org.elasticsearch.cluster.service.ClusterService;
 import org.elasticsearch.common.inject.Inject;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.index.engine.Engine;
+import org.elasticsearch.index.mapper.MapperParsingException;
 import org.elasticsearch.index.mapper.Mapping;
 import org.elasticsearch.index.mapper.SourceToParse;
 import org.elasticsearch.index.shard.IndexShard;
 import org.elasticsearch.index.shard.ShardId;
-import org.elasticsearch.index.translog.Translog.Location;
 import org.elasticsearch.indices.IndexAlreadyExistsException;
 import org.elasticsearch.indices.IndicesService;
 import org.elasticsearch.tasks.Task;
@@ -60,7 +60,7 @@ import org.elasticsearch.transport.TransportService;
  * <li><b>allowIdGeneration</b>: If the id is set not, should it be generated. Defaults to <tt>true</tt>.
  * </ul>
  */
-public class TransportIndexAction extends TransportWriteAction<IndexRequest, IndexResponse> {
+public class TransportIndexAction extends TransportWriteAction<IndexRequest, IndexRequest, IndexResponse> {
 
     private final AutoCreateIndex autoCreateIndex;
     private final boolean allowIdGeneration;
@@ -76,7 +76,7 @@ public class TransportIndexAction extends TransportWriteAction<IndexRequest, Ind
                                 ActionFilters actionFilters, IndexNameExpressionResolver indexNameExpressionResolver,
                                 AutoCreateIndex autoCreateIndex) {
         super(settings, IndexAction.NAME, transportService, clusterService, indicesService, threadPool, shardStateAction,
-            actionFilters, indexNameExpressionResolver, IndexRequest::new, ThreadPool.Names.INDEX);
+            actionFilters, indexNameExpressionResolver, IndexRequest::new, IndexRequest::new, ThreadPool.Names.INDEX);
         this.mappingUpdatedAction = mappingUpdatedAction;
         this.createIndexAction = createIndexAction;
         this.autoCreateIndex = autoCreateIndex;
@@ -140,65 +140,88 @@ public class TransportIndexAction extends TransportWriteAction<IndexRequest, Ind
     }
 
     @Override
-    protected WriteResult<IndexResponse> onPrimaryShard(IndexRequest request, IndexShard indexShard) throws Exception {
-        return executeIndexRequestOnPrimary(request, indexShard, mappingUpdatedAction);
+    protected WritePrimaryResult shardOperationOnPrimary(IndexRequest request, IndexShard primary) throws Exception {
+        final Engine.IndexResult indexResult = executeIndexRequestOnPrimary(request, primary, mappingUpdatedAction);
+        final IndexResponse response = indexResult.hasFailure() ? null :
+                new IndexResponse(primary.shardId(), request.type(), request.id(), indexResult.getVersion(),
+                        indexResult.isCreated());
+        return new WritePrimaryResult(request, response, indexResult.getTranslogLocation(), indexResult.getFailure(), primary);
     }
 
     @Override
-    protected Location onReplicaShard(IndexRequest request, IndexShard indexShard) {
-        return executeIndexRequestOnReplica(request, indexShard).getTranslogLocation();
+    protected WriteReplicaResult shardOperationOnReplica(IndexRequest request, IndexShard replica) throws Exception {
+        final Engine.IndexResult indexResult = executeIndexRequestOnReplica(request, replica);
+        return new WriteReplicaResult(request, indexResult.getTranslogLocation(), indexResult.getFailure(), replica);
     }
 
     /**
      * Execute the given {@link IndexRequest} on a replica shard, throwing a
      * {@link RetryOnReplicaException} if the operation needs to be re-tried.
      */
-    public static Engine.Index executeIndexRequestOnReplica(IndexRequest request, IndexShard indexShard) {
-        final ShardId shardId = indexShard.shardId();
+    public static Engine.IndexResult executeIndexRequestOnReplica(IndexRequest request, IndexShard replica) {
+        final ShardId shardId = replica.shardId();
         SourceToParse sourceToParse = SourceToParse.source(SourceToParse.Origin.REPLICA, shardId.getIndexName(), request.type(), request.id(), request.source())
                 .routing(request.routing()).parent(request.parent()).timestamp(request.timestamp()).ttl(request.ttl());
 
-        final Engine.Index operation = indexShard.prepareIndexOnReplica(sourceToParse, request.version(), request.versionType(), request.getAutoGeneratedTimestamp(), request.isRetry());
+        final Engine.Index operation;
+        try {
+            operation = replica.prepareIndexOnReplica(sourceToParse, request.version(), request.versionType(), request.getAutoGeneratedTimestamp(), request.isRetry());
+        } catch (MapperParsingException e) {
+            return new Engine.IndexResult(e, request.version());
+        }
         Mapping update = operation.parsedDoc().dynamicMappingsUpdate();
         if (update != null) {
             throw new RetryOnReplicaException(shardId, "Mappings are not available on the replica yet, triggered update: " + update);
         }
-        indexShard.index(operation);
-        return operation;
+        return replica.index(operation);
     }
 
     /** Utility method to prepare an index operation on primary shards */
-    public static Engine.Index prepareIndexOperationOnPrimary(IndexRequest request, IndexShard indexShard) {
+    static Engine.Index prepareIndexOperationOnPrimary(IndexRequest request, IndexShard primary) {
         SourceToParse sourceToParse = SourceToParse.source(SourceToParse.Origin.PRIMARY, request.index(), request.type(), request.id(), request.source())
             .routing(request.routing()).parent(request.parent()).timestamp(request.timestamp()).ttl(request.ttl());
-        return indexShard.prepareIndexOnPrimary(sourceToParse, request.version(), request.versionType(), request.getAutoGeneratedTimestamp(), request.isRetry());
+        return primary.prepareIndexOnPrimary(sourceToParse, request.version(), request.versionType(), request.getAutoGeneratedTimestamp(), request.isRetry());
     }
 
-    public static WriteResult<IndexResponse> executeIndexRequestOnPrimary(IndexRequest request, IndexShard indexShard,
+    public static Engine.IndexResult executeIndexRequestOnPrimary(IndexRequest request, IndexShard primary,
             MappingUpdatedAction mappingUpdatedAction) throws Exception {
-        Engine.Index operation = prepareIndexOperationOnPrimary(request, indexShard);
+        Engine.Index operation;
+        try {
+            operation = prepareIndexOperationOnPrimary(request, primary);
+        } catch (MapperParsingException | IllegalArgumentException e) {
+            return new Engine.IndexResult(e, request.version());
+        }
         Mapping update = operation.parsedDoc().dynamicMappingsUpdate();
-        final ShardId shardId = indexShard.shardId();
+        final ShardId shardId = primary.shardId();
         if (update != null) {
-            mappingUpdatedAction.updateMappingOnMaster(shardId.getIndex(), request.type(), update);
-            operation = prepareIndexOperationOnPrimary(request, indexShard);
+            // can throw timeout exception when updating mappings or ISE for attempting to update default mappings
+            // which are bubbled up
+            try {
+                mappingUpdatedAction.updateMappingOnMaster(shardId.getIndex(), request.type(), update);
+            } catch (IllegalArgumentException e) {
+                // throws IAE on conflicts merging dynamic mappings
+                return new Engine.IndexResult(e, request.version());
+            }
+            try {
+                operation = prepareIndexOperationOnPrimary(request, primary);
+            } catch (MapperParsingException | IllegalArgumentException e) {
+                return new Engine.IndexResult(e, request.version());
+            }
             update = operation.parsedDoc().dynamicMappingsUpdate();
             if (update != null) {
                 throw new ReplicationOperation.RetryOnPrimaryException(shardId,
                     "Dynamic mappings are not available on the node that holds the primary yet");
             }
         }
-        indexShard.index(operation);
-
-        // update the version on request so it will happen on the replicas
-        final long version = operation.version();
-        request.version(version);
-        request.versionType(request.versionType().versionTypeForReplicationAndRecovery());
-
-        assert request.versionType().validateVersionForWrites(request.version());
-
-        IndexResponse response = new IndexResponse(shardId, request.type(), request.id(), request.version(), operation.isCreated());
-        return new WriteResult<>(response, operation.getTranslogLocation());
+        Engine.IndexResult result = primary.index(operation);
+        if (result.hasFailure() == false) {
+            // update the version on request so it will happen on the replicas
+            final long version = result.getVersion();
+            request.version(version);
+            request.versionType(request.versionType().versionTypeForReplicationAndRecovery());
+            assert request.versionType().validateVersionForWrites(request.version());
+        }
+        return result;
     }
 }
 

core/src/main/java/org/elasticsearch/action/ingest/DeletePipelineRequestBuilder.java

@@ -32,4 +32,12 @@ public class DeletePipelineRequestBuilder extends ActionRequestBuilder<DeletePip
         super(client, action, new DeletePipelineRequest(id));
     }
 
+    /**
+     * Sets the id of the pipeline to delete.
+     */
+    public DeletePipelineRequestBuilder setId(String id) {
+        request.setId(id);
+        return this;
+    }
+
 }

core/src/main/java/org/elasticsearch/action/support/TransportAction.java

@@ -138,17 +138,8 @@ public abstract class TransportAction<Request extends ActionRequest<Request>, Re
             listener = new TaskResultStoringActionListener<>(taskManager, task, listener);
         }
 
-        if (filters.length == 0) {
-            try {
-                doExecute(task, request, listener);
-            } catch(Exception e) {
-                logger.trace("Error during transport action execution.", e);
-                listener.onFailure(e);
-            }
-        } else {
-            RequestFilterChain<Request, Response> requestFilterChain = new RequestFilterChain<>(this, logger);
-            requestFilterChain.proceed(task, actionName, request, listener);
-        }
+        RequestFilterChain<Request, Response> requestFilterChain = new RequestFilterChain<>(this, logger);
+        requestFilterChain.proceed(task, actionName, request, listener);
     }
 
     protected void doExecute(Task task, Request request, ActionListener<Response> listener) {

core/src/main/java/org/elasticsearch/action/support/replication/ReplicationOperation.java

@@ -32,6 +32,7 @@ import org.elasticsearch.cluster.routing.AllocationId;
 import org.elasticsearch.cluster.routing.IndexRoutingTable;
 import org.elasticsearch.cluster.routing.IndexShardRoutingTable;
 import org.elasticsearch.cluster.routing.ShardRouting;
+import org.elasticsearch.common.Nullable;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.util.set.Sets;
 import org.elasticsearch.index.engine.VersionConflictEngineException;
@@ -112,22 +113,24 @@ public class ReplicationOperation<
         pendingActions.incrementAndGet();
         primaryResult = primary.perform(request);
         final ReplicaRequest replicaRequest = primaryResult.replicaRequest();
-        assert replicaRequest.primaryTerm() > 0 : "replicaRequest doesn't have a primary term";
-        if (logger.isTraceEnabled()) {
-            logger.trace("[{}] op [{}] completed on primary for request [{}]", primaryId, opType, request);
+        if (replicaRequest != null) {
+            assert replicaRequest.primaryTerm() > 0 : "replicaRequest doesn't have a primary term";
+            if (logger.isTraceEnabled()) {
+                logger.trace("[{}] op [{}] completed on primary for request [{}]", primaryId, opType, request);
+            }
+
+            // we have to get a new state after successfully indexing into the primary in order to honour recovery semantics.
+            // we have to make sure that every operation indexed into the primary after recovery start will also be replicated
+            // to the recovery target. If we use an old cluster state, we may miss a relocation that has started since then.
+            ClusterState clusterState = clusterStateSupplier.get();
+            final List<ShardRouting> shards = getShards(primaryId, clusterState);
+            Set<String> inSyncAllocationIds = getInSyncAllocationIds(primaryId, clusterState);
+
+            markUnavailableShardsAsStale(replicaRequest, inSyncAllocationIds, shards);
+
+            performOnReplicas(replicaRequest, shards);
         }
 
-        // we have to get a new state after successfully indexing into the primary in order to honour recovery semantics.
-        // we have to make sure that every operation indexed into the primary after recovery start will also be replicated
-        // to the recovery target. If we use an old cluster state, we may miss a relocation that has started since then.
-        ClusterState clusterState = clusterStateSupplier.get();
-        final List<ShardRouting> shards = getShards(primaryId, clusterState);
-        Set<String> inSyncAllocationIds = getInSyncAllocationIds(primaryId, clusterState);
-
-        markUnavailableShardsAsStale(replicaRequest, inSyncAllocationIds, shards);
-
-        performOnReplicas(replicaRequest, shards);
-
         successfulShards.incrementAndGet();
         decPendingAndFinishIfNeeded();
     }
@@ -419,7 +422,11 @@ public class ReplicationOperation<
 
     public interface PrimaryResult<R extends ReplicationRequest<R>> {
 
-        R replicaRequest();
+        /**
+         * @return null if no operation needs to be sent to a replica
+         * (for example when the operation failed on the primary due to a parsing exception)
+         */
+        @Nullable R replicaRequest();
 
         void setShardInfo(ReplicationResponse.ShardInfo shardInfo);
     }

core/src/main/java/org/elasticsearch/action/support/replication/ReplicationResponse.java

@@ -24,7 +24,6 @@ import org.elasticsearch.ExceptionsHelper;
 import org.elasticsearch.action.ActionResponse;
 import org.elasticsearch.action.ShardOperationFailedException;
 import org.elasticsearch.common.Nullable;
-import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.io.stream.Streamable;
@@ -34,6 +33,7 @@ import org.elasticsearch.index.shard.ShardId;
 import org.elasticsearch.rest.RestStatus;
 
 import java.io.IOException;
+import java.util.Arrays;
 
 /**
  * Base class for write action responses.
@@ -162,7 +162,11 @@ public class ReplicationResponse extends ActionResponse {
 
         @Override
         public String toString() {
-            return Strings.toString(this);
+            return "ShardInfo{" +
+                "total=" + total +
+                ", successful=" + successful +
+                ", failures=" + Arrays.toString(failures) +
+                '}';
         }
 
         public static ShardInfo readShardInfo(StreamInput in) throws IOException {

core/src/main/java/org/elasticsearch/action/support/replication/TransportReplicationAction.java

@@ -24,6 +24,7 @@ import org.elasticsearch.ElasticsearchException;
 import org.elasticsearch.action.ActionListener;
 import org.elasticsearch.action.ActionListenerResponseHandler;
 import org.elasticsearch.action.UnavailableShardsException;
+import org.elasticsearch.action.admin.indices.flush.ShardFlushRequest;
 import org.elasticsearch.action.support.ActionFilters;
 import org.elasticsearch.action.support.ActiveShardCount;
 import org.elasticsearch.action.support.TransportAction;
@@ -178,7 +179,7 @@ public abstract class TransportReplicationAction<
      * @param shardRequest the request to the replica shard
      * @param replica      the replica shard to perform the operation on
      */
-    protected abstract ReplicaResult shardOperationOnReplica(ReplicaRequest shardRequest, IndexShard replica);
+    protected abstract ReplicaResult shardOperationOnReplica(ReplicaRequest shardRequest, IndexShard replica) throws Exception;
 
     /**
      * Cluster level block to check before request execution
@@ -207,7 +208,7 @@ public abstract class TransportReplicationAction<
 
     protected boolean retryPrimaryException(final Throwable e) {
         return e.getClass() == ReplicationOperation.RetryOnPrimaryException.class
-            || TransportActions.isShardNotAvailableException(e);
+                || TransportActions.isShardNotAvailableException(e);
     }
 
     class OperationTransportHandler implements TransportRequestHandler<Request> {
@@ -310,17 +311,10 @@ public abstract class TransportReplicationAction<
                     final IndexMetaData indexMetaData = clusterService.state().getMetaData().index(request.shardId().getIndex());
                     final boolean executeOnReplicas = (indexMetaData == null) || shouldExecuteReplication(indexMetaData.getSettings());
                     final ActionListener<Response> listener = createResponseListener(primaryShardReference);
-                    createReplicatedOperation(request, new ActionListener<PrimaryResult>() {
-                        @Override
-                        public void onResponse(PrimaryResult result) {
-                            result.respond(listener);
-                        }
-
-                        @Override
-                        public void onFailure(Exception e) {
-                            listener.onFailure(e);
-                        }
-                    }, primaryShardReference, executeOnReplicas).execute();
+                    createReplicatedOperation(request,
+                            ActionListener.wrap(result -> result.respond(listener), listener::onFailure),
+                            primaryShardReference, executeOnReplicas)
+                            .execute();
                 }
             } catch (Exception e) {
                 Releasables.closeWhileHandlingException(primaryShardReference); // release shard operation lock before responding to caller
@@ -376,11 +370,24 @@ public abstract class TransportReplicationAction<
 
     protected class PrimaryResult implements ReplicationOperation.PrimaryResult<ReplicaRequest> {
         final ReplicaRequest replicaRequest;
-        final Response finalResponse;
+        final Response finalResponseIfSuccessful;
+        final Exception finalFailure;
 
-        public PrimaryResult(ReplicaRequest replicaRequest, Response finalResponse) {
+        /**
+         * Result of executing a primary operation
+         * expects <code>finalResponseIfSuccessful</code> or <code>finalFailure</code> to be not-null
+         */
+        public PrimaryResult(ReplicaRequest replicaRequest, Response finalResponseIfSuccessful, Exception finalFailure) {
+            assert finalFailure != null ^ finalResponseIfSuccessful != null
+                    : "either a response or a failure has to be not null, " +
+                    "found [" + finalFailure + "] failure and ["+ finalResponseIfSuccessful + "] response";
             this.replicaRequest = replicaRequest;
-            this.finalResponse = finalResponse;
+            this.finalResponseIfSuccessful = finalResponseIfSuccessful;
+            this.finalFailure = finalFailure;
+        }
+
+        public PrimaryResult(ReplicaRequest replicaRequest, Response replicationResponse) {
+            this(replicaRequest, replicationResponse, null);
         }
 
         @Override
@@ -390,22 +397,37 @@ public abstract class TransportReplicationAction<
 
         @Override
         public void setShardInfo(ReplicationResponse.ShardInfo shardInfo) {
-            finalResponse.setShardInfo(shardInfo);
+            if (finalResponseIfSuccessful != null) {
+                finalResponseIfSuccessful.setShardInfo(shardInfo);
+            }
         }
 
         public void respond(ActionListener<Response> listener) {
-            listener.onResponse(finalResponse);
+            if (finalResponseIfSuccessful != null) {
+                listener.onResponse(finalResponseIfSuccessful);
+            } else {
+                listener.onFailure(finalFailure);
+            }
         }
     }
 
     protected class ReplicaResult {
-        /**
-         * Public constructor so subclasses can call it.
-         */
-        public ReplicaResult() {}
+        final Exception finalFailure;
+
+        public ReplicaResult(Exception finalFailure) {
+            this.finalFailure = finalFailure;
+        }
+
+        public ReplicaResult() {
+            this(null);
+        }
 
         public void respond(ActionListener<TransportResponse.Empty> listener) {
-            listener.onResponse(TransportResponse.Empty.INSTANCE);
+            if (finalFailure == null) {
+                listener.onResponse(TransportResponse.Empty.INSTANCE);
+            } else {
+                listener.onFailure(finalFailure);
+            }
         }
     }
 
@@ -481,6 +503,7 @@ public abstract class TransportReplicationAction<
                             transportReplicaAction,
                             request),
                     e);
+                request.onRetry();
                 final ThreadContext.StoredContext context = threadPool.getThreadContext().newStoredContext();
                 observer.waitForNextChange(new ClusterStateObserver.Listener() {
                     @Override
@@ -902,7 +925,9 @@ public abstract class TransportReplicationAction<
         @Override
         public PrimaryResult perform(Request request) throws Exception {
             PrimaryResult result = shardOperationOnPrimary(request, indexShard);
-            result.replicaRequest().primaryTerm(indexShard.getPrimaryTerm());
+            if (result.replicaRequest() != null) {
+                result.replicaRequest().primaryTerm(indexShard.getPrimaryTerm());
+            }
             return result;
         }
 

core/src/main/java/org/elasticsearch/action/support/replication/TransportWriteAction.java

@@ -44,81 +44,63 @@ import java.util.function.Supplier;
 
 /**
  * Base class for transport actions that modify data in some shard like index, delete, and shardBulk.
+ * Allows performing async actions (e.g. refresh) after performing write operations on primary and replica shards
  */
 public abstract class TransportWriteAction<
             Request extends ReplicatedWriteRequest<Request>,
+            ReplicaRequest extends ReplicatedWriteRequest<ReplicaRequest>,
             Response extends ReplicationResponse & WriteResponse
-        > extends TransportReplicationAction<Request, Request, Response> {
+        > extends TransportReplicationAction<Request, ReplicaRequest, Response> {
 
     protected TransportWriteAction(Settings settings, String actionName, TransportService transportService,
             ClusterService clusterService, IndicesService indicesService, ThreadPool threadPool, ShardStateAction shardStateAction,
             ActionFilters actionFilters, IndexNameExpressionResolver indexNameExpressionResolver, Supplier<Request> request,
-            String executor) {
+                                   Supplier<ReplicaRequest> replicaRequest, String executor) {
         super(settings, actionName, transportService, clusterService, indicesService, threadPool, shardStateAction, actionFilters,
-                indexNameExpressionResolver, request, request, executor);
+                indexNameExpressionResolver, request, replicaRequest, executor);
     }
 
     /**
-     * Called on the primary with a reference to the {@linkplain IndexShard} to modify.
-     */
-    protected abstract WriteResult<Response> onPrimaryShard(Request request, IndexShard indexShard) throws Exception;
-
-    /**
-     * Called once per replica with a reference to the {@linkplain IndexShard} to modify.
+     * Called on the primary with a reference to the primary {@linkplain IndexShard} to modify.
      *
-     * @return the translog location of the {@linkplain IndexShard} after the write was completed or null if no write occurred
+     * @return the result of the operation on primary, including current translog location and operation response and failure
+     * async refresh is performed on the <code>primary</code> shard according to the <code>Request</code> refresh policy
      */
-    protected abstract Translog.Location onReplicaShard(Request request, IndexShard indexShard);
-
     @Override
-    protected final WritePrimaryResult shardOperationOnPrimary(Request request, IndexShard primary) throws Exception {
-        WriteResult<Response> result = onPrimaryShard(request, primary);
-        return new WritePrimaryResult(request, result.getResponse(), result.getLocation(), primary);
-    }
-
-    @Override
-    protected final WriteReplicaResult shardOperationOnReplica(Request request, IndexShard replica) {
-        Translog.Location location = onReplicaShard(request, replica);
-        return new WriteReplicaResult(replica, request, location);
-    }
+    protected abstract WritePrimaryResult shardOperationOnPrimary(Request request, IndexShard primary) throws Exception;
 
     /**
-     * Simple result from a write action. Write actions have static method to return these so they can integrate with bulk.
+     * Called once per replica with a reference to the replica {@linkplain IndexShard} to modify.
+     *
+     * @return the result of the operation on replica, including current translog location and operation response and failure
+     * async refresh is performed on the <code>replica</code> shard according to the <code>ReplicaRequest</code> refresh policy
      */
-    public static class WriteResult<Response extends ReplicationResponse> {
-        private final Response response;
-        private final Translog.Location location;
-
-        public WriteResult(Response response, @Nullable Location location) {
-            this.response = response;
-            this.location = location;
-        }
-
-        public Response getResponse() {
-            return response;
-        }
-
-        public Translog.Location getLocation() {
-            return location;
-        }
-    }
+    @Override
+    protected abstract WriteReplicaResult shardOperationOnReplica(ReplicaRequest request, IndexShard replica) throws Exception;
 
     /**
      * Result of taking the action on the primary.
      */
-    class WritePrimaryResult extends PrimaryResult implements RespondingWriteResult {
+    protected class WritePrimaryResult extends PrimaryResult implements RespondingWriteResult {
         boolean finishedAsyncActions;
         ActionListener<Response> listener = null;
 
-        public WritePrimaryResult(Request request, Response finalResponse,
-                                  @Nullable Translog.Location location,
-                                  IndexShard indexShard) {
-            super(request, finalResponse);
-            /*
-             * We call this before replication because this might wait for a refresh and that can take a while. This way we wait for the
-             * refresh in parallel on the primary and on the replica.
-             */
-            new AsyncAfterWriteAction(indexShard, request, location, this, logger).run();
+        public WritePrimaryResult(ReplicaRequest request, @Nullable Response finalResponse,
+                                  @Nullable Location location, @Nullable Exception operationFailure,
+                                  IndexShard primary) {
+            super(request, finalResponse, operationFailure);
+            assert location == null || operationFailure == null
+                    : "expected either failure to be null or translog location to be null, " +
+                    "but found: [" + location + "] translog location and [" + operationFailure + "] failure";
+            if (operationFailure != null) {
+                this.finishedAsyncActions = true;
+            } else {
+                /*
+                 * We call this before replication because this might wait for a refresh and that can take a while.
+                 * This way we wait for the refresh in parallel on the primary and on the replica.
+                 */
+                new AsyncAfterWriteAction(primary, request, location, this, logger).run();
+            }
         }
 
         @Override
@@ -147,7 +129,7 @@ public abstract class TransportWriteAction<
 
         @Override
         public synchronized void onSuccess(boolean forcedRefresh) {
-            finalResponse.setForcedRefresh(forcedRefresh);
+            finalResponseIfSuccessful.setForcedRefresh(forcedRefresh);
             finishedAsyncActions = true;
             respondIfPossible(null);
         }
@@ -156,12 +138,18 @@ public abstract class TransportWriteAction<
     /**
      * Result of taking the action on the replica.
      */
-    class WriteReplicaResult extends ReplicaResult implements RespondingWriteResult {
+    protected class WriteReplicaResult extends ReplicaResult implements RespondingWriteResult {
         boolean finishedAsyncActions;
         private ActionListener<TransportResponse.Empty> listener;
 
-        public WriteReplicaResult(IndexShard indexShard, ReplicatedWriteRequest<?> request, Translog.Location location) {
-            new AsyncAfterWriteAction(indexShard, request, location, this, logger).run();
+        public WriteReplicaResult(ReplicaRequest request, @Nullable Location location,
+                                  @Nullable Exception operationFailure, IndexShard replica) {
+            super(operationFailure);
+            if (operationFailure != null) {
+                this.finishedAsyncActions = true;
+            } else {
+                new AsyncAfterWriteAction(replica, request, location, this, logger).run();
+            }
         }
 
         @Override

core/src/main/java/org/elasticsearch/client/ClusterAdminClient.java

@@ -563,6 +563,11 @@ public interface ClusterAdminClient extends ElasticsearchClient {
      */
     DeletePipelineRequestBuilder prepareDeletePipeline();
 
+    /**
+     * Deletes a stored ingest pipeline
+     */
+    DeletePipelineRequestBuilder prepareDeletePipeline(String id);
+
     /**
      * Returns a stored ingest pipeline
      */

core/src/main/java/org/elasticsearch/client/support/AbstractClient.java

@@ -1096,6 +1096,11 @@ public abstract class AbstractClient extends AbstractComponent implements Client
             return new DeletePipelineRequestBuilder(this, DeletePipelineAction.INSTANCE);
         }
 
+        @Override
+        public DeletePipelineRequestBuilder prepareDeletePipeline(String id) {
+            return new DeletePipelineRequestBuilder(this, DeletePipelineAction.INSTANCE, id);
+        }
+
         @Override
         public void getPipeline(GetPipelineRequest request, ActionListener<GetPipelineResponse> listener) {
             execute(GetPipelineAction.INSTANCE, request, listener);

core/src/main/java/org/elasticsearch/cluster/ClusterState.java

@@ -274,15 +274,16 @@ public class ClusterState implements ToXContent, Diffable<ClusterState> {
         return routingNodes;
     }
 
-    public String prettyPrint() {
+    @Override
+    public String toString() {
         StringBuilder sb = new StringBuilder();
         sb.append("cluster uuid: ").append(metaData.clusterUUID()).append("\n");
         sb.append("version: ").append(version).append("\n");
         sb.append("state uuid: ").append(stateUUID).append("\n");
         sb.append("from_diff: ").append(wasReadFromDiff).append("\n");
         sb.append("meta data version: ").append(metaData.version()).append("\n");
+        final String TAB = "   ";
         for (IndexMetaData indexMetaData : metaData) {
-            final String TAB = "   ";
             sb.append(TAB).append(indexMetaData.getIndex());
             sb.append(": v[").append(indexMetaData.getVersion()).append("]\n");
             for (int shard = 0; shard < indexMetaData.getNumberOfShards(); shard++) {
@@ -291,24 +292,19 @@ public class ClusterState implements ToXContent, Diffable<ClusterState> {
                 sb.append("isa_ids ").append(indexMetaData.inSyncAllocationIds(shard)).append("\n");
             }
         }
-        sb.append(blocks().prettyPrint());
-        sb.append(nodes().prettyPrint());
-        sb.append(routingTable().prettyPrint());
-        sb.append(getRoutingNodes().prettyPrint());
-        return sb.toString();
-    }
-
-    @Override
-    public String toString() {
-        try {
-            XContentBuilder builder = XContentFactory.jsonBuilder().prettyPrint();
-            builder.startObject();
-            toXContent(builder, EMPTY_PARAMS);
-            builder.endObject();
-            return builder.string();
-        } catch (IOException e) {
-            return "{ \"error\" : \"" + e.getMessage() + "\"}";
+        sb.append(blocks());
+        sb.append(nodes());
+        sb.append(routingTable());
+        sb.append(getRoutingNodes());
+        if (customs.isEmpty() == false) {
+            sb.append("customs:\n");
+            for (ObjectObjectCursor<String, Custom> cursor : customs) {
+                final String type = cursor.key;
+                final Custom custom = cursor.value;
+                sb.append(TAB).append(type).append(": ").append(custom);
+            }
         }
+        return sb.toString();
     }
 
     /**

core/src/main/java/org/elasticsearch/cluster/NodeConnectionsService.java

@@ -36,6 +36,7 @@ import org.elasticsearch.discovery.zen.NodesFaultDetection;
 import org.elasticsearch.threadpool.ThreadPool;
 import org.elasticsearch.transport.TransportService;
 
+import java.util.List;
 import java.util.concurrent.ConcurrentMap;
 import java.util.concurrent.ScheduledFuture;
 
@@ -75,10 +76,10 @@ public class NodeConnectionsService extends AbstractLifecycleComponent {
         this.reconnectInterval = NodeConnectionsService.CLUSTER_NODE_RECONNECT_INTERVAL_SETTING.get(settings);
     }
 
-    public void connectToAddedNodes(ClusterChangedEvent event) {
+    public void connectToNodes(List<DiscoveryNode> addedNodes) {
 
         // TODO: do this in parallel (and wait)
-        for (final DiscoveryNode node : event.nodesDelta().addedNodes()) {
+        for (final DiscoveryNode node : addedNodes) {
             try (Releasable ignored = nodeLocks.acquire(node)) {
                 Integer current = nodes.put(node, 0);
                 assert current == null : "node " + node + " was added in event but already in internal nodes";
@@ -87,8 +88,8 @@ public class NodeConnectionsService extends AbstractLifecycleComponent {
         }
     }
 
-    public void disconnectFromRemovedNodes(ClusterChangedEvent event) {
-        for (final DiscoveryNode node : event.nodesDelta().removedNodes()) {
+    public void disconnectFromNodes(List<DiscoveryNode> removedNodes) {
+        for (final DiscoveryNode node : removedNodes) {
             try (Releasable ignored = nodeLocks.acquire(node)) {
                 Integer current = nodes.remove(node);
                 assert current != null : "node " + node + " was removed in event but not in internal nodes";

core/src/main/java/org/elasticsearch/cluster/action/shard/ShardStateAction.java

@@ -164,7 +164,7 @@ public class ShardStateAction extends AbstractComponent {
             @Override
             public void onNewClusterState(ClusterState state) {
                 if (logger.isTraceEnabled()) {
-                    logger.trace("new cluster state [{}] after waiting for master election to fail shard entry [{}]", state.prettyPrint(), shardEntry);
+                    logger.trace("new cluster state [{}] after waiting for master election to fail shard entry [{}]", state, shardEntry);
                 }
                 sendShardAction(actionName, observer, shardEntry, listener);
             }

core/src/main/java/org/elasticsearch/cluster/block/ClusterBlocks.java

@@ -199,7 +199,8 @@ public class ClusterBlocks extends AbstractDiffable<ClusterBlocks> {
         return new ClusterBlockException(unmodifiableSet(blocks.collect(toSet())));
     }
 
-    public String prettyPrint() {
+    @Override
+    public String toString() {
         if (global.isEmpty() && indices().isEmpty()) {
             return "";
         }

core/src/main/java/org/elasticsearch/cluster/metadata/MetaData.java

@@ -97,10 +97,29 @@ public class MetaData implements Iterable<IndexMetaData>, Diffable<MetaData>, Fr
         SNAPSHOT
     }
 
+    /**
+     * Indicates that this custom metadata will be returned as part of an API call but will not be persisted
+     */
     public static EnumSet<XContentContext> API_ONLY = EnumSet.of(XContentContext.API);
+
+    /**
+     * Indicates that this custom metadata will be returned as part of an API call and will be persisted between
+     * node restarts, but will not be a part of a snapshot global state
+     */
     public static EnumSet<XContentContext> API_AND_GATEWAY = EnumSet.of(XContentContext.API, XContentContext.GATEWAY);
+
+    /**
+     * Indicates that this custom metadata will be returned as part of an API call and stored as a part of
+     * a snapshot global state, but will not be persisted between node restarts
+     */
     public static EnumSet<XContentContext> API_AND_SNAPSHOT = EnumSet.of(XContentContext.API, XContentContext.SNAPSHOT);
 
+    /**
+     * Indicates that this custom metadata will be returned as part of an API call, stored as a part of
+     * a snapshot global state, and will be persisted between node restarts
+     */
+    public static EnumSet<XContentContext> ALL_CONTEXTS = EnumSet.allOf(XContentContext.class);
+
     public interface Custom extends Diffable<Custom>, ToXContent {
 
         String type();

core/src/main/java/org/elasticsearch/cluster/metadata/MetaDataCreateIndexService.java

@@ -352,7 +352,9 @@ public class MetaDataCreateIndexService extends AbstractComponent {
                                 throw mpe;
                             }
 
-                            final QueryShardContext queryShardContext = indexService.newQueryShardContext();
+                            // the context is only used for validation so it's fine to pass fake values for the shard id and the current
+                            // timestamp
+                            final QueryShardContext queryShardContext = indexService.newQueryShardContext(0, null, () -> 0L);
                             for (Alias alias : request.aliases()) {
                                 if (Strings.hasLength(alias.filter())) {
                                     aliasValidator.validateAliasFilter(alias.name(), alias.filter(), queryShardContext);

core/src/main/java/org/elasticsearch/cluster/metadata/MetaDataIndexAliasesService.java

@@ -149,7 +149,9 @@ public class MetaDataIndexAliasesService extends AbstractComponent {
                             }
                             indices.put(action.getIndex(), indexService);
                         }
-                        aliasValidator.validateAliasFilter(alias, filter, indexService.newQueryShardContext());
+                        // the context is only used for validation so it's fine to pass fake values for the shard id and the current
+                        // timestamp
+                        aliasValidator.validateAliasFilter(alias, filter, indexService.newQueryShardContext(0, null, () -> 0L));
                     }
                 };
                 changed |= action.apply(newAliasValidator, metadata, index);

core/src/main/java/org/elasticsearch/cluster/node/DiscoveryNodes.java

@@ -26,7 +26,6 @@ import org.elasticsearch.Version;
 import org.elasticsearch.cluster.AbstractDiffable;
 import org.elasticsearch.common.Booleans;
 import org.elasticsearch.common.Nullable;
-import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.collect.ImmutableOpenMap;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
@@ -398,14 +397,6 @@ public class DiscoveryNodes extends AbstractDiffable<DiscoveryNodes> implements
 
     @Override
     public String toString() {
-        StringBuilder sb = new StringBuilder();
-        sb.append("{");
-        sb.append(Strings.collectionToDelimitedString(this, ","));
-        sb.append("}");
-        return sb.toString();
-    }
-
-    public String prettyPrint() {
         StringBuilder sb = new StringBuilder();
         sb.append("nodes: \n");
         for (DiscoveryNode node : this) {

core/src/main/java/org/elasticsearch/cluster/routing/RoutingNodes.java

@@ -391,7 +391,8 @@ public class RoutingNodes implements Iterable<RoutingNode> {
         return shards;
     }
 
-    public String prettyPrint() {
+    @Override
+    public String toString() {
         StringBuilder sb = new StringBuilder("routing_nodes:\n");
         for (RoutingNode routingNode : this) {
             sb.append(routingNode.prettyPrint());

core/src/main/java/org/elasticsearch/cluster/routing/RoutingService.java

@@ -109,7 +109,7 @@ public class RoutingService extends AbstractLifecycleComponent {
                     rerouting.set(false);
                     ClusterState state = clusterService.state();
                     if (logger.isTraceEnabled()) {
-                        logger.error((Supplier<?>) () -> new ParameterizedMessage("unexpected failure during [{}], current state:\n{}", source, state.prettyPrint()), e);
+                        logger.error((Supplier<?>) () -> new ParameterizedMessage("unexpected failure during [{}], current state:\n{}", source, state), e);
                     } else {
                         logger.error((Supplier<?>) () -> new ParameterizedMessage("unexpected failure during [{}], current state version [{}]", source, state.version()), e);
                     }
@@ -118,7 +118,7 @@ public class RoutingService extends AbstractLifecycleComponent {
         } catch (Exception e) {
             rerouting.set(false);
             ClusterState state = clusterService.state();
-            logger.warn((Supplier<?>) () -> new ParameterizedMessage("failed to reroute routing table, current state:\n{}", state.prettyPrint()), e);
+            logger.warn((Supplier<?>) () -> new ParameterizedMessage("failed to reroute routing table, current state:\n{}", state), e);
         }
     }
 }

core/src/main/java/org/elasticsearch/cluster/routing/RoutingTable.java

@@ -613,7 +613,8 @@ public class RoutingTable implements Iterable<IndexRoutingTable>, Diffable<Routi
         }
     }
 
-    public String prettyPrint() {
+    @Override
+    public String toString() {
         StringBuilder sb = new StringBuilder("routing_table (version ").append(version).append("):\n");
         for (ObjectObjectCursor<String, IndexRoutingTable> entry : indicesRouting) {
             sb.append(entry.value.prettyPrint()).append('\n');

core/src/main/java/org/elasticsearch/cluster/routing/allocation/IndexMetaDataUpdater.java

@@ -233,7 +233,7 @@ public class IndexMetaDataUpdater extends RoutingChangesObserver.AbstractRouting
                 Set<String> oldInSyncAllocations = oldIndexMetaData.inSyncAllocationIds(shardNumber);
                 Set<String> idsToRemove = shardEntry.getValue().stream().map(e -> e.getAllocationId()).collect(Collectors.toSet());
                 assert idsToRemove.stream().allMatch(id -> oldRoutingTable.getByAllocationId(shardEntry.getKey(), id) == null) :
-                    "removing stale ids: " + idsToRemove + ", some of which have still a routing entry: " + oldRoutingTable.prettyPrint();
+                    "removing stale ids: " + idsToRemove + ", some of which have still a routing entry: " + oldRoutingTable;
                 Set<String> remainingInSyncAllocations = Sets.difference(oldInSyncAllocations, idsToRemove);
                 assert remainingInSyncAllocations.isEmpty() == false : "Set of in-sync ids cannot become empty for shard " +
                     shardEntry.getKey() + " (before: " + oldInSyncAllocations + ", ids to remove: " + idsToRemove + ")";

core/src/main/java/org/elasticsearch/cluster/routing/allocation/allocator/BalancedShardsAllocator.java

@@ -126,6 +126,18 @@ public class BalancedShardsAllocator extends AbstractComponent implements Shards
         balancer.balance();
     }
 
+    /**
+     * Returns a decision on rebalancing a single shard to form a more optimal cluster balance.  This
+     * method is not used in itself for cluster rebalancing because all shards from all indices are
+     * taken into account when making rebalancing decisions.  This method is only intended to be used
+     * from the cluster allocation explain API to explain possible rebalancing decisions for a single
+     * shard.
+     */
+    public RebalanceDecision decideRebalance(final ShardRouting shard, final RoutingAllocation allocation) {
+        assert allocation.debugDecision() : "debugDecision should be set in explain mode";
+        return new Balancer(logger, allocation, weightFunction, threshold).decideRebalance(shard);
+    }
+
     /**
      * Returns the currently configured delta threshold
      */
@@ -267,11 +279,18 @@ public class BalancedShardsAllocator extends AbstractComponent implements Shards
             return new NodeSorter(nodesArray(), weight, this);
         }
 
+        /**
+         * The absolute value difference between two weights.
+         */
         private static float absDelta(float lower, float higher) {
             assert higher >= lower : higher + " lt " + lower +" but was expected to be gte";
             return Math.abs(higher - lower);
         }
 
+        /**
+         * Returns {@code true} iff the weight delta between two nodes is under a defined threshold.
+         * See {@link #THRESHOLD_SETTING} for defining the threshold.
+         */
         private static boolean lessThan(float delta, float threshold) {
             /* deltas close to the threshold are "rounded" to the threshold manually
                to prevent floating point problems if the delta is very close to the
@@ -309,6 +328,110 @@ public class BalancedShardsAllocator extends AbstractComponent implements Shards
             balanceByWeights();
         }
 
+        /**
+         * Makes a decision about moving a single shard to a different node to form a more
+         * optimally balanced cluster.  This method is invoked from the cluster allocation
+         * explain API only.
+         */
+        private RebalanceDecision decideRebalance(final ShardRouting shard) {
+            if (shard.started() == false) {
+                // cannot rebalance a shard that isn't started
+                return RebalanceDecision.NOT_TAKEN;
+            }
+
+            Decision canRebalance = allocation.deciders().canRebalance(shard, allocation);
+
+            if (allocation.hasPendingAsyncFetch()) {
+                return new RebalanceDecision(
+                    canRebalance,
+                    Type.NO,
+                    "cannot rebalance due to in-flight shard store fetches, otherwise allocation may prematurely rebalance a shard to " +
+                        "a node that is soon to receive another shard assignment upon completion of the shard store fetch, " +
+                        "rendering the cluster imbalanced again"
+                );
+            }
+
+            sorter.reset(shard.getIndexName());
+            ModelNode[] modelNodes = sorter.modelNodes;
+            final String currentNodeId = shard.currentNodeId();
+            // find currently assigned node
+            ModelNode currentNode = null;
+            for (ModelNode node : modelNodes) {
+                if (node.getNodeId().equals(currentNodeId)) {
+                    currentNode = node;
+                    break;
+                }
+            }
+            assert currentNode != null : "currently assigned node could not be found";
+
+            // balance the shard, if a better node can be found
+            final float currentWeight = sorter.weight(currentNode);
+            final AllocationDeciders deciders = allocation.deciders();
+            final String idxName = shard.getIndexName();
+            Map<String, NodeRebalanceDecision> nodeDecisions = new HashMap<>(modelNodes.length - 1);
+            Type rebalanceDecisionType = Type.NO;
+            String assignedNodeId = null;
+            for (ModelNode node : modelNodes) {
+                if (node == currentNode) {
+                    continue; // skip over node we're currently allocated to it
+                }
+                final Decision canAllocate = deciders.canAllocate(shard, node.getRoutingNode(), allocation);
+                // the current weight of the node in the cluster, as computed by the weight function;
+                // this is a comparison of the number of shards on this node to the number of shards
+                // that should be on each node on average (both taking the cluster as a whole into account
+                // as well as shards per index)
+                final float nodeWeight = sorter.weight(node);
+                // if the node we are examining has a worse (higher) weight than the node the shard is
+                // assigned to, then there is no way moving the shard to the node with the worse weight
+                // can make the balance of the cluster better, so we check for that here
+                final boolean betterWeightThanCurrent = nodeWeight <= currentWeight;
+                boolean rebalanceConditionsMet = false;
+                boolean deltaAboveThreshold = false;
+                float weightWithShardAdded = Float.POSITIVE_INFINITY;
+                if (betterWeightThanCurrent) {
+                    // get the delta between the weights of the node we are checking and the node that holds the shard
+                    final float currentDelta = absDelta(nodeWeight, currentWeight);
+                    // checks if the weight delta is above a certain threshold; if it is not above a certain threshold,
+                    // then even though the node we are examining has a better weight and may make the cluster balance
+                    // more even, it doesn't make sense to execute the heavyweight operation of relocating a shard unless
+                    // the gains make it worth it, as defined by the threshold
+                    deltaAboveThreshold = lessThan(currentDelta, threshold) == false;
+                    // simulate the weight of the node if we were to relocate the shard to it
+                    weightWithShardAdded = weight.weightShardAdded(this, node, idxName);
+                    // calculate the delta of the weights of the two nodes if we were to add the shard to the
+                    // node in question and move it away from the node that currently holds it.
+                    final float proposedDelta = weightWithShardAdded - weight.weightShardRemoved(this, currentNode, idxName);
+                    rebalanceConditionsMet = deltaAboveThreshold && proposedDelta < currentDelta;
+                    // if the simulated weight delta with the shard moved away is better than the weight delta
+                    // with the shard remaining on the current node, and we are allowed to allocate to the
+                    // node in question, then allow the rebalance
+                    if (rebalanceConditionsMet && canAllocate.type().higherThan(rebalanceDecisionType)) {
+                        // rebalance to the node, only will get overwritten if the decision here is to
+                        // THROTTLE and we get a decision with YES on another node
+                        rebalanceDecisionType = canAllocate.type();
+                        assignedNodeId = node.getNodeId();
+                    }
+                }
+                nodeDecisions.put(node.getNodeId(), new NodeRebalanceDecision(
+                    rebalanceConditionsMet ? canAllocate.type() : Type.NO,
+                    canAllocate,
+                    betterWeightThanCurrent,
+                    deltaAboveThreshold,
+                    nodeWeight,
+                    weightWithShardAdded)
+                );
+            }
+
+
+            if (canRebalance.type() != Type.YES) {
+                return new RebalanceDecision(canRebalance, canRebalance.type(), "rebalancing is not allowed", null,
+                                                nodeDecisions, currentWeight);
+            } else {
+                return RebalanceDecision.decision(canRebalance, rebalanceDecisionType, assignedNodeId,
+                                                  nodeDecisions, currentWeight, threshold);
+            }
+        }
+
         public Map<DiscoveryNode, Float> weighShard(ShardRouting shard) {
             final ModelNode[] modelNodes = sorter.modelNodes;
             final float[] weights = sorter.weights;
@@ -539,7 +662,7 @@ public class BalancedShardsAllocator extends AbstractComponent implements Shards
         public MoveDecision makeMoveDecision(final ShardRouting shardRouting) {
             if (shardRouting.started() == false) {
                 // we can only move started shards
-                return MoveDecision.DECISION_NOT_TAKEN;
+                return MoveDecision.NOT_TAKEN;
             }
 
             final boolean explain = allocation.debugDecision();
@@ -1110,15 +1233,11 @@ public class BalancedShardsAllocator extends AbstractComponent implements Shards
         private final String finalExplanation;
         @Nullable
         private final String assignedNodeId;
-        @Nullable
-        private final Map<String, WeightedDecision> nodeDecisions;
 
-        protected RelocationDecision(Type finalDecision, String finalExplanation, String assignedNodeId,
-                                     Map<String, WeightedDecision> nodeDecisions) {
+        protected RelocationDecision(Type finalDecision, String finalExplanation, String assignedNodeId) {
             this.finalDecision = finalDecision;
             this.finalExplanation = finalExplanation;
             this.assignedNodeId = assignedNodeId;
-            this.nodeDecisions = nodeDecisions;
         }
 
         /**
@@ -1153,15 +1272,6 @@ public class BalancedShardsAllocator extends AbstractComponent implements Shards
         public String getAssignedNodeId() {
             return assignedNodeId;
         }
-
-        /**
-         * Gets the individual node-level decisions that went into making the final decision as represented by
-         * {@link #getFinalDecisionType()}.  The map that is returned has the node id as the key and a {@link WeightedDecision}.
-         */
-        @Nullable
-        public Map<String, WeightedDecision> getNodeDecisions() {
-            return nodeDecisions;
-        }
     }
 
     /**
@@ -1169,18 +1279,21 @@ public class BalancedShardsAllocator extends AbstractComponent implements Shards
      */
     public static final class MoveDecision extends RelocationDecision {
         /** a constant representing no decision taken */
-        public static final MoveDecision DECISION_NOT_TAKEN = new MoveDecision(null, null, null, null, null);
+        public static final MoveDecision NOT_TAKEN = new MoveDecision(null, null, null, null, null);
         /** cached decisions so we don't have to recreate objects for common decisions when not in explain mode. */
         private static final MoveDecision CACHED_STAY_DECISION = new MoveDecision(Decision.YES, Type.NO, null, null, null);
         private static final MoveDecision CACHED_CANNOT_MOVE_DECISION = new MoveDecision(Decision.NO, Type.NO, null, null, null);
 
         @Nullable
         private final Decision canRemainDecision;
+        @Nullable
+        private final Map<String, WeightedDecision> nodeDecisions;
 
         private MoveDecision(Decision canRemainDecision, Type finalDecision, String finalExplanation,
                              String assignedNodeId, Map<String, WeightedDecision> nodeDecisions) {
-            super(finalDecision, finalExplanation, assignedNodeId, nodeDecisions);
+            super(finalDecision, finalExplanation, assignedNodeId);
             this.canRemainDecision = canRemainDecision;
+            this.nodeDecisions = nodeDecisions != null ? Collections.unmodifiableMap(nodeDecisions) : null;
         }
 
         /**
@@ -1250,6 +1363,147 @@ public class BalancedShardsAllocator extends AbstractComponent implements Shards
         public boolean cannotRemain() {
             return isDecisionTaken() && canRemainDecision.type() == Type.NO;
         }
+
+        /**
+         * Gets the individual node-level decisions that went into making the final decision as represented by
+         * {@link #getFinalDecisionType()}.  The map that is returned has the node id as the key and a {@link WeightedDecision}.
+         */
+        @Nullable
+        public Map<String, WeightedDecision> getNodeDecisions() {
+            return nodeDecisions;
+        }
+    }
+
+    /**
+     * Represents a decision to move a started shard to form a more optimally balanced cluster.
+     */
+    public static final class RebalanceDecision extends RelocationDecision {
+        /** a constant representing no decision taken */
+        public static final RebalanceDecision NOT_TAKEN = new RebalanceDecision(null, null, null, null, null, Float.POSITIVE_INFINITY);
+
+        @Nullable
+        private final Decision canRebalanceDecision;
+        @Nullable
+        private final Map<String, NodeRebalanceDecision> nodeDecisions;
+        private float currentWeight;
+
+        protected RebalanceDecision(Decision canRebalanceDecision, Type finalDecision, String finalExplanation) {
+            this(canRebalanceDecision, finalDecision, finalExplanation, null, null, Float.POSITIVE_INFINITY);
+        }
+
+        protected RebalanceDecision(Decision canRebalanceDecision, Type finalDecision, String finalExplanation,
+                                    String assignedNodeId, Map<String, NodeRebalanceDecision> nodeDecisions, float currentWeight) {
+            super(finalDecision, finalExplanation, assignedNodeId);
+            this.canRebalanceDecision = canRebalanceDecision;
+            this.nodeDecisions = nodeDecisions != null ? Collections.unmodifiableMap(nodeDecisions) : null;
+            this.currentWeight = currentWeight;
+        }
+
+        /**
+         * Creates a new {@link RebalanceDecision}, computing the explanation based on the decision parameters.
+         */
+        public static RebalanceDecision decision(Decision canRebalanceDecision, Type finalDecision, String assignedNodeId,
+                                                 Map<String, NodeRebalanceDecision> nodeDecisions, float currentWeight, float threshold) {
+            final String explanation = produceFinalExplanation(finalDecision, assignedNodeId, threshold);
+            return new RebalanceDecision(canRebalanceDecision, finalDecision, explanation, assignedNodeId, nodeDecisions, currentWeight);
+        }
+
+        /**
+         * Returns the decision for being allowed to rebalance the shard.
+         */
+        @Nullable
+        public Decision getCanRebalanceDecision() {
+            return canRebalanceDecision;
+        }
+
+        /**
+         * Gets the individual node-level decisions that went into making the final decision as represented by
+         * {@link #getFinalDecisionType()}.  The map that is returned has the node id as the key and a {@link NodeRebalanceDecision}.
+         */
+        @Nullable
+        public Map<String, NodeRebalanceDecision> getNodeDecisions() {
+            return nodeDecisions;
+        }
+
+        private static String produceFinalExplanation(final Type finalDecisionType, final String assignedNodeId, final float threshold) {
+            final String finalExplanation;
+            if (assignedNodeId != null) {
+                if (finalDecisionType == Type.THROTTLE) {
+                    finalExplanation = "throttle moving shard to node [" + assignedNodeId + "], as it is " +
+                                           "currently busy with other shard relocations";
+                } else {
+                    finalExplanation = "moving shard to node [" + assignedNodeId + "] to form a more balanced cluster";
+                }
+            } else {
+                finalExplanation = "cannot rebalance shard, no other node exists that would form a more balanced " +
+                                       "cluster within the defined threshold [" + threshold + "]";
+            }
+            return finalExplanation;
+        }
+    }
+
+    /**
+     * A node-level explanation for the decision to rebalance a shard.
+     */
+    public static final class NodeRebalanceDecision {
+        private final Type nodeDecisionType;
+        private final Decision canAllocate;
+        private final boolean betterWeightThanCurrent;
+        private final boolean deltaAboveThreshold;
+        private final float currentWeight;
+        private final float weightWithShardAdded;
+
+        NodeRebalanceDecision(Type nodeDecisionType, Decision canAllocate, boolean betterWeightThanCurrent,
+                              boolean deltaAboveThreshold, float currentWeight, float weightWithShardAdded) {
+            this.nodeDecisionType = Objects.requireNonNull(nodeDecisionType);
+            this.canAllocate = Objects.requireNonNull(canAllocate);
+            this.betterWeightThanCurrent = betterWeightThanCurrent;
+            this.deltaAboveThreshold = deltaAboveThreshold;
+            this.currentWeight = currentWeight;
+            this.weightWithShardAdded = weightWithShardAdded;
+        }
+
+        /**
+         * Returns the decision to rebalance to the node.
+         */
+        public Type getNodeDecisionType() {
+            return nodeDecisionType;
+        }
+
+        /**
+         * Returns whether the shard is allowed to be allocated to the node.
+         */
+        public Decision getCanAllocateDecision() {
+            return canAllocate;
+        }
+
+        /**
+         * Returns whether the weight of the node is better than the weight of the node where the shard currently resides.
+         */
+        public boolean isBetterWeightThanCurrent() {
+            return betterWeightThanCurrent;
+        }
+
+        /**
+         * Returns if the weight delta by assigning to this node was above the threshold to warrant a rebalance.
+         */
+        public boolean isDeltaAboveThreshold() {
+            return deltaAboveThreshold;
+        }
+
+        /**
+         * Returns the current weight of the node if the shard is not added to the node.
+         */
+        public float getCurrentWeight() {
+            return currentWeight;
+        }
+
+        /**
+         * Returns the weight of the node if the shard is added to the node.
+         */
+        public float getWeightWithShardAdded() {
+            return weightWithShardAdded;
+        }
     }
 
 }

core/src/main/java/org/elasticsearch/cluster/routing/allocation/decider/Decision.java

@@ -222,7 +222,7 @@ public abstract class Decision implements ToXContent {
         }
 
         /**
-         * Returns the explanation string, fully formatted. Only formats the string once
+         * Returns the explanation string, fully formatted.  Only formats the string once.
          */
         @Nullable
         public String getExplanation() {

core/src/main/java/org/elasticsearch/cluster/routing/allocation/decider/EnableAllocationDecider.java

@@ -103,28 +103,33 @@ public class EnableAllocationDecider extends AllocationDecider {
 
         final IndexMetaData indexMetaData = allocation.metaData().getIndexSafe(shardRouting.index());
         final Allocation enable;
+        final boolean usedIndexSetting;
         if (INDEX_ROUTING_ALLOCATION_ENABLE_SETTING.exists(indexMetaData.getSettings())) {
             enable = INDEX_ROUTING_ALLOCATION_ENABLE_SETTING.get(indexMetaData.getSettings());
+            usedIndexSetting = true;
         } else {
             enable = this.enableAllocation;
+            usedIndexSetting = false;
         }
         switch (enable) {
             case ALL:
                 return allocation.decision(Decision.YES, NAME, "all allocations are allowed");
             case NONE:
-                return allocation.decision(Decision.NO, NAME, "no allocations are allowed");
+                return allocation.decision(Decision.NO, NAME, "no allocations are allowed due to {}", setting(enable, usedIndexSetting));
             case NEW_PRIMARIES:
                 if (shardRouting.primary() && shardRouting.active() == false &&
                     shardRouting.recoverySource().getType() != RecoverySource.Type.EXISTING_STORE) {
                     return allocation.decision(Decision.YES, NAME, "new primary allocations are allowed");
                 } else {
-                    return allocation.decision(Decision.NO, NAME, "non-new primary allocations are forbidden");
+                    return allocation.decision(Decision.NO, NAME, "non-new primary allocations are forbidden due to {}",
+                                                setting(enable, usedIndexSetting));
                 }
             case PRIMARIES:
                 if (shardRouting.primary()) {
                     return allocation.decision(Decision.YES, NAME, "primary allocations are allowed");
                 } else {
-                    return allocation.decision(Decision.NO, NAME, "replica allocations are forbidden");
+                    return allocation.decision(Decision.NO, NAME, "replica allocations are forbidden due to {}",
+                                                setting(enable, usedIndexSetting));
                 }
             default:
                 throw new IllegalStateException("Unknown allocation option");
@@ -139,33 +144,60 @@ public class EnableAllocationDecider extends AllocationDecider {
 
         Settings indexSettings = allocation.metaData().getIndexSafe(shardRouting.index()).getSettings();
         final Rebalance enable;
+        final boolean usedIndexSetting;
         if (INDEX_ROUTING_REBALANCE_ENABLE_SETTING.exists(indexSettings)) {
             enable = INDEX_ROUTING_REBALANCE_ENABLE_SETTING.get(indexSettings);
+            usedIndexSetting = true;
         } else {
             enable = this.enableRebalance;
+            usedIndexSetting = false;
         }
         switch (enable) {
             case ALL:
                 return allocation.decision(Decision.YES, NAME, "all rebalancing is allowed");
             case NONE:
-                return allocation.decision(Decision.NO, NAME, "no rebalancing is allowed");
+                return allocation.decision(Decision.NO, NAME, "no rebalancing is allowed due to {}", setting(enable, usedIndexSetting));
             case PRIMARIES:
                 if (shardRouting.primary()) {
                     return allocation.decision(Decision.YES, NAME, "primary rebalancing is allowed");
                 } else {
-                    return allocation.decision(Decision.NO, NAME, "replica rebalancing is forbidden");
+                    return allocation.decision(Decision.NO, NAME, "replica rebalancing is forbidden due to {}",
+                                                setting(enable, usedIndexSetting));
                 }
             case REPLICAS:
                 if (shardRouting.primary() == false) {
                     return allocation.decision(Decision.YES, NAME, "replica rebalancing is allowed");
                 } else {
-                    return allocation.decision(Decision.NO, NAME, "primary rebalancing is forbidden");
+                    return allocation.decision(Decision.NO, NAME, "primary rebalancing is forbidden due to {}",
+                                                setting(enable, usedIndexSetting));
                 }
             default:
                 throw new IllegalStateException("Unknown rebalance option");
         }
     }
 
+    private static String setting(Allocation allocation, boolean usedIndexSetting) {
+        StringBuilder buf = new StringBuilder("[");
+        if (usedIndexSetting) {
+            buf.append(INDEX_ROUTING_ALLOCATION_ENABLE_SETTING.getKey());
+        } else {
+            buf.append(CLUSTER_ROUTING_ALLOCATION_ENABLE_SETTING.getKey());
+        }
+        buf.append("=").append(allocation.toString().toLowerCase(Locale.ROOT)).append("]");
+        return buf.toString();
+    }
+
+    private static String setting(Rebalance rebalance, boolean usedIndexSetting) {
+        StringBuilder buf = new StringBuilder("[");
+        if (usedIndexSetting) {
+            buf.append(INDEX_ROUTING_REBALANCE_ENABLE_SETTING.getKey());
+        } else {
+            buf.append(CLUSTER_ROUTING_REBALANCE_ENABLE_SETTING.getKey());
+        }
+        buf.append("=").append(rebalance.toString().toLowerCase(Locale.ROOT)).append("]");
+        return buf.toString();
+    }
+
     /**
      * Allocation values or rather their string representation to be used used with
      * {@link EnableAllocationDecider#CLUSTER_ROUTING_ALLOCATION_ENABLE_SETTING} /

core/src/main/java/org/elasticsearch/cluster/service/ClusterService.java

@@ -562,9 +562,9 @@ public class ClusterService extends AbstractLifecycleComponent {
                         executionTime,
                         previousClusterState.version(),
                         tasksSummary,
-                        previousClusterState.nodes().prettyPrint(),
-                        previousClusterState.routingTable().prettyPrint(),
-                        previousClusterState.getRoutingNodes().prettyPrint()),
+                        previousClusterState.nodes(),
+                        previousClusterState.routingTable(),
+                        previousClusterState.getRoutingNodes()),
                     e);
             }
             warnAboutSlowTaskIfNeeded(executionTime, tasksSummary);
@@ -656,7 +656,7 @@ public class ClusterService extends AbstractLifecycleComponent {
             newClusterState.status(ClusterState.ClusterStateStatus.BEING_APPLIED);
 
             if (logger.isTraceEnabled()) {
-                logger.trace("cluster state updated, source [{}]\n{}", tasksSummary, newClusterState.prettyPrint());
+                logger.trace("cluster state updated, source [{}]\n{}", tasksSummary, newClusterState);
             } else if (logger.isDebugEnabled()) {
                 logger.debug("cluster state updated, version [{}], source [{}]", newClusterState.version(), tasksSummary);
             }
@@ -671,7 +671,7 @@ public class ClusterService extends AbstractLifecycleComponent {
                 }
             }
 
-            nodeConnectionsService.connectToAddedNodes(clusterChangedEvent);
+            nodeConnectionsService.connectToNodes(clusterChangedEvent.nodesDelta().addedNodes());
 
             // if we are the master, publish the new state to all nodes
             // we publish here before we send a notification to all the listeners, since if it fails
@@ -686,6 +686,8 @@ public class ClusterService extends AbstractLifecycleComponent {
                         (Supplier<?>) () -> new ParameterizedMessage(
                             "failing [{}]: failed to commit cluster state version [{}]", tasksSummary, version),
                         t);
+                    // ensure that list of connected nodes in NodeConnectionsService is in-sync with the nodes of the current cluster state
+                    nodeConnectionsService.disconnectFromNodes(clusterChangedEvent.nodesDelta().addedNodes());
                     proccessedListeners.forEach(task -> task.listener.onFailure(task.source, t));
                     return;
                 }
@@ -711,7 +713,7 @@ public class ClusterService extends AbstractLifecycleComponent {
                 }
             }
 
-            nodeConnectionsService.disconnectFromRemovedNodes(clusterChangedEvent);
+            nodeConnectionsService.disconnectFromNodes(clusterChangedEvent.nodesDelta().removedNodes());
 
             newClusterState.status(ClusterState.ClusterStateStatus.APPLIED);
 
@@ -757,7 +759,7 @@ public class ClusterService extends AbstractLifecycleComponent {
             TimeValue executionTime = TimeValue.timeValueMillis(Math.max(0, TimeValue.nsecToMSec(currentTimeInNanos() - startTimeNS)));
             final long version = newClusterState.version();
             final String stateUUID = newClusterState.stateUUID();
-            final String prettyPrint = newClusterState.prettyPrint();
+            final String fullState = newClusterState.toString();
             logger.warn(
                 (Supplier<?>) () -> new ParameterizedMessage(
                     "failed to apply updated cluster state in [{}]:\nversion [{}], uuid [{}], source [{}]\n{}",
@@ -765,7 +767,7 @@ public class ClusterService extends AbstractLifecycleComponent {
                     version,
                     stateUUID,
                     tasksSummary,
-                    prettyPrint),
+                    fullState),
                 e);
             // TODO: do we want to call updateTask.onFailure here?
         }
@@ -824,9 +826,7 @@ public class ClusterService extends AbstractLifecycleComponent {
                     (Supplier<?>) () -> new ParameterizedMessage(
                         "exception thrown by listener while notifying of cluster state processed from [{}], old cluster state:\n" +
                             "{}\nnew cluster state:\n{}",
-                        source,
-                        oldState.prettyPrint(),
-                        newState.prettyPrint()),
+                        source, oldState, newState),
                     e);
             }
         }

core/src/main/java/org/elasticsearch/common/component/AbstractLifecycleComponent.java

@@ -21,6 +21,7 @@ package org.elasticsearch.common.component;
 
 import org.elasticsearch.common.settings.Settings;
 
+import java.io.IOException;
 import java.util.List;
 import java.util.concurrent.CopyOnWriteArrayList;
 
@@ -101,11 +102,17 @@ public abstract class AbstractLifecycleComponent extends AbstractComponent imple
             listener.beforeClose();
         }
         lifecycle.moveToClosed();
-        doClose();
+        try {
+            doClose();
+        } catch (IOException e) {
+            // TODO: we need to separate out closing (ie shutting down) services, vs releasing runtime transient
+            // structures. Shutting down services should use IOUtils.close
+            logger.warn("failed to close " + getClass().getName(), e);
+        }
         for (LifecycleListener listener : listeners) {
             listener.afterClose();
         }
     }
 
-    protected abstract void doClose();
+    protected abstract void doClose() throws IOException;
 }

core/src/main/java/org/elasticsearch/common/io/stream/BytesStreamOutput.java

@@ -69,7 +69,7 @@ public class BytesStreamOutput extends StreamOutput implements BytesStream {
 
     @Override
     public void writeByte(byte b) throws IOException {
-        ensureCapacity(count+1);
+        ensureCapacity(count + 1L);
         bytes.set(count, b);
         count++;
     }
@@ -87,7 +87,7 @@ public class BytesStreamOutput extends StreamOutput implements BytesStream {
         }
 
         // get enough pages for new size
-        ensureCapacity(count+length);
+        ensureCapacity(((long) count) + length);
 
         // bulk copy
         bytes.set(count, b, offset, length);
@@ -113,22 +113,17 @@ public class BytesStreamOutput extends StreamOutput implements BytesStream {
     }
 
     @Override
-    public void seek(long position) throws IOException {
-        if (position > Integer.MAX_VALUE) {
-            throw new IllegalArgumentException("position " + position + " > Integer.MAX_VALUE");
-        }
-
-        count = (int)position;
-        ensureCapacity(count);
+    public void seek(long position) {
+        ensureCapacity(position);
+        count = (int) position;
     }
 
     public void skip(int length) {
-        count += length;
-        ensureCapacity(count);
+        seek(((long) count) + length);
     }
 
     @Override
-    public void close() throws IOException {
+    public void close() {
         // empty for now.
     }
 
@@ -156,7 +151,10 @@ public class BytesStreamOutput extends StreamOutput implements BytesStream {
         return bytes.ramBytesUsed();
     }
 
-    private void ensureCapacity(int offset) {
+    private void ensureCapacity(long offset) {
+        if (offset > Integer.MAX_VALUE) {
+            throw new IllegalArgumentException(getClass().getSimpleName() + " cannot hold more than 2GB of data");
+        }
         bytes = bigArrays.grow(bytes, offset);
     }
 

core/src/main/java/org/elasticsearch/common/util/ExtensionPoint.java

@@ -1,250 +0,0 @@
-/*
- * Licensed to Elasticsearch under one or more contributor
- * license agreements. See the NOTICE file distributed with
- * this work for additional information regarding copyright
- * ownership. Elasticsearch licenses this file to you under
- * the Apache License, Version 2.0 (the "License"); you may
- * not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *    http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing,
- * software distributed under the License is distributed on an
- * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
- * KIND, either express or implied.  See the License for the
- * specific language governing permissions and limitations
- * under the License.
- */
-
-package org.elasticsearch.common.util;
-
-import org.elasticsearch.common.inject.Binder;
-import org.elasticsearch.common.inject.multibindings.MapBinder;
-import org.elasticsearch.common.inject.multibindings.Multibinder;
-import org.elasticsearch.common.settings.Settings;
-
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.HashSet;
-import java.util.Map;
-import java.util.Set;
-
-/**
- * This class defines an official elasticsearch extension point. It registers
- * all extensions by a single name and ensures that extensions are not registered
- * more than once.
- */
-public abstract class ExtensionPoint {
-    protected final String name;
-    protected final Class<?>[] singletons;
-
-    /**
-     * Creates a new extension point
-     *
-     * @param name           the human readable underscore case name of the extension point. This is used in error messages etc.
-     * @param singletons     a list of singletons to bind with this extension point - these are bound in {@link #bind(Binder)}
-     */
-    public ExtensionPoint(String name, Class<?>... singletons) {
-        this.name = name;
-        this.singletons = singletons;
-    }
-
-    /**
-     * Binds the extension as well as the singletons to the given guice binder.
-     *
-     * @param binder the binder to use
-     */
-    public final void bind(Binder binder) {
-        for (Class<?> c : singletons) {
-            binder.bind(c).asEagerSingleton();
-        }
-        bindExtensions(binder);
-    }
-
-    /**
-     * Subclasses can bind their type, map or set extensions here.
-     */
-    protected abstract void bindExtensions(Binder binder);
-
-    /**
-     * A map based extension point which allows to register keyed implementations ie. parsers or some kind of strategies.
-     */
-    public static class ClassMap<T> extends ExtensionPoint {
-        protected final Class<T> extensionClass;
-        protected final Map<String, Class<? extends T>> extensions = new HashMap<>();
-        private final Set<String> reservedKeys;
-
-        /**
-         * Creates a new {@link ClassMap}
-         *
-         * @param name           the human readable underscore case name of the extension point. This is used in error messages etc.
-         * @param extensionClass the base class that should be extended
-         * @param singletons     a list of singletons to bind with this extension point - these are bound in {@link #bind(Binder)}
-         * @param reservedKeys   a set of reserved keys by internal implementations
-         */
-        public ClassMap(String name, Class<T> extensionClass, Set<String> reservedKeys, Class<?>... singletons) {
-            super(name, singletons);
-            this.extensionClass = extensionClass;
-            this.reservedKeys = reservedKeys;
-        }
-
-        /**
-         * Returns the extension for the given key or <code>null</code>
-         */
-        public Class<? extends T> getExtension(String type) {
-            return extensions.get(type);
-        }
-
-        /**
-         * Registers an extension class for a given key. This method will thr
-         *
-         * @param key       the extensions key
-         * @param extension the extension
-         * @throws IllegalArgumentException iff the key is already registered or if the key is a reserved key for an internal implementation
-         */
-        public final void registerExtension(String key, Class<? extends T> extension) {
-            if (extensions.containsKey(key) || reservedKeys.contains(key)) {
-                throw new IllegalArgumentException("Can't register the same [" + this.name + "] more than once for [" + key + "]");
-            }
-            extensions.put(key, extension);
-        }
-
-        @Override
-        protected final void bindExtensions(Binder binder) {
-            MapBinder<String, T> parserMapBinder = MapBinder.newMapBinder(binder, String.class, extensionClass);
-            for (Map.Entry<String, Class<? extends T>> clazz : extensions.entrySet()) {
-                parserMapBinder.addBinding(clazz.getKey()).to(clazz.getValue());
-            }
-        }
-    }
-
-    /**
-     * A Type extension point which basically allows to registered keyed extensions like {@link ClassMap}
-     * but doesn't instantiate and bind all the registered key value pairs but instead replace a singleton based on a given setting via {@link #bindType(Binder, Settings, String, String)}
-     * Note: {@link #bind(Binder)} is not supported by this class
-     */
-    public static final class SelectedType<T> extends ClassMap<T> {
-
-        public SelectedType(String name, Class<T> extensionClass) {
-            super(name, extensionClass, Collections.emptySet());
-        }
-
-        /**
-         * Binds the extension class to the class that is registered for the give configured for the settings key in
-         * the settings object.
-         *
-         * @param binder       the binder to use
-         * @param settings     the settings to look up the key to find the implementation to bind
-         * @param settingsKey  the key to use with the settings
-         * @param defaultValue the default value if the settings do not contain the key, or null if there is no default
-         * @return the actual bound type key
-         */
-        public String bindType(Binder binder, Settings settings, String settingsKey, String defaultValue) {
-            final String type = settings.get(settingsKey, defaultValue);
-            if (type == null) {
-                throw new IllegalArgumentException("Missing setting [" + settingsKey + "]");
-            }
-            final Class<? extends T> instance = getExtension(type);
-            if (instance == null) {
-                throw new IllegalArgumentException("Unknown [" + this.name + "] type [" + type + "] possible values: "
-                    + extensions.keySet());
-            }
-            if (extensionClass == instance) {
-                binder.bind(extensionClass).asEagerSingleton();
-            } else {
-                binder.bind(extensionClass).to(instance).asEagerSingleton();
-            }
-            return type;
-        }
-
-    }
-
-    /**
-     * A set based extension point which allows to register extended classes that might be used to chain additional functionality etc.
-     */
-    public static final class ClassSet<T> extends ExtensionPoint {
-        protected final Class<T> extensionClass;
-        private final Set<Class<? extends T>> extensions = new HashSet<>();
-
-        /**
-         * Creates a new {@link ClassSet}
-         *
-         * @param name           the human readable underscore case name of the extension point. This is used in error messages etc.
-         * @param extensionClass the base class that should be extended
-         * @param singletons     a list of singletons to bind with this extension point - these are bound in {@link #bind(Binder)}
-         */
-        public ClassSet(String name, Class<T> extensionClass, Class<?>... singletons) {
-            super(name, singletons);
-            this.extensionClass = extensionClass;
-        }
-
-        /**
-         * Registers a new extension
-         *
-         * @param extension the extension to register
-         * @throws IllegalArgumentException iff the class is already registered
-         */
-        public void registerExtension(Class<? extends T> extension) {
-            if (extensions.contains(extension)) {
-                throw new IllegalArgumentException("Can't register the same [" + this.name + "] more than once for [" + extension.getName() + "]");
-            }
-            extensions.add(extension);
-        }
-
-        @Override
-        protected void bindExtensions(Binder binder) {
-            Multibinder<T> allocationMultibinder = Multibinder.newSetBinder(binder, extensionClass);
-            for (Class<? extends T> clazz : extensions) {
-                binder.bind(clazz).asEagerSingleton();
-                allocationMultibinder.addBinding().to(clazz);
-            }
-        }
-
-        public boolean isEmpty() {
-            return extensions.isEmpty();
-        }
-    }
-
-    /**
-     * A an instance of a map, mapping one instance value to another. Both key and value are instances, not classes
-     * like with other extension points.
-     */
-    public static final class InstanceMap<K, V> extends ExtensionPoint {
-        private final Map<K, V> map = new HashMap<>();
-        private final Class<K> keyType;
-        private final Class<V> valueType;
-
-        /**
-         * Creates a new {@link ClassSet}
-         *
-         * @param name           the human readable underscore case name of the extension point. This is used in error messages.
-         * @param singletons     a list of singletons to bind with this extension point - these are bound in {@link #bind(Binder)}
-         */
-        public InstanceMap(String name, Class<K> keyType, Class<V> valueType, Class<?>... singletons) {
-            super(name, singletons);
-            this.keyType = keyType;
-            this.valueType = valueType;
-        }
-
-        /**
-         * Registers a mapping from {@code key} to {@code value}
-         *
-         * @throws IllegalArgumentException iff the key is already registered
-         */
-        public void registerExtension(K key, V value) {
-            V old = map.put(key, value);
-            if (old != null) {
-                throw new IllegalArgumentException("Cannot register [" + this.name + "] with key [" + key + "] to [" + value + "], already registered to [" + old + "]");
-            }
-        }
-
-        @Override
-        protected void bindExtensions(Binder binder) {
-            MapBinder<K, V> mapBinder = MapBinder.newMapBinder(binder, keyType, valueType);
-            for (Map.Entry<K, V> entry : map.entrySet()) {
-                mapBinder.addBinding(entry.getKey()).toInstance(entry.getValue());
-            }
-        }
-    }
-}

core/src/main/java/org/elasticsearch/common/xcontent/XContentGenerator.java

@@ -94,4 +94,9 @@ public interface XContentGenerator extends Closeable, Flushable {
 
     void copyCurrentStructure(XContentParser parser) throws IOException;
 
+    /**
+     * Returns {@code true} if this XContentGenerator has been closed. A closed generator can not do any more output.
+     */
+    boolean isClosed();
+
 }

core/src/main/java/org/elasticsearch/common/xcontent/json/JsonXContentGenerator.java

@@ -419,4 +419,8 @@ public class JsonXContentGenerator implements XContentGenerator {
         generator.close();
     }
 
+    @Override
+    public boolean isClosed() {
+        return generator.isClosed();
+    }
 }

core/src/main/java/org/elasticsearch/common/xcontent/support/XContentMapValues.java

@@ -185,8 +185,8 @@ public class XContentMapValues {
         // we want all sub properties to match as soon as an object matches
 
         return (map) -> filter(map,
-            include, include.getInitialState(),
-            exclude, exclude.getInitialState(),
+            include, 0,
+            exclude, 0,
             matchAllAutomaton);
     }
 
@@ -237,7 +237,7 @@ public class XContentMapValues {
                     // the object matched, so consider that the include matches every inner property
                     // we only care about excludes now
                     subIncludeAutomaton = matchAllAutomaton;
-                    subIncludeState = includeAutomaton.getInitialState();
+                    subIncludeState = 0;
                 }
             }
 

core/src/main/java/org/elasticsearch/discovery/DiscoveryModule.java

@@ -19,20 +19,6 @@
 
 package org.elasticsearch.discovery;
 
-import org.elasticsearch.common.inject.AbstractModule;
-import org.elasticsearch.common.network.NetworkService;
-import org.elasticsearch.common.settings.Setting;
-import org.elasticsearch.common.settings.Setting.Property;
-import org.elasticsearch.common.settings.Settings;
-import org.elasticsearch.common.util.ExtensionPoint;
-import org.elasticsearch.discovery.zen.ZenDiscovery;
-import org.elasticsearch.plugins.DiscoveryPlugin;
-import org.elasticsearch.transport.TransportService;
-import org.elasticsearch.discovery.zen.ZenPing;
-import org.elasticsearch.discovery.zen.ZenPingService;
-import org.elasticsearch.discovery.zen.UnicastHostsProvider;
-import org.elasticsearch.discovery.zen.UnicastZenPing;
-
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
@@ -41,6 +27,16 @@ import java.util.Objects;
 import java.util.function.Function;
 import java.util.function.Supplier;
 
+import org.elasticsearch.common.inject.AbstractModule;
+import org.elasticsearch.common.network.NetworkService;
+import org.elasticsearch.common.settings.Setting;
+import org.elasticsearch.common.settings.Setting.Property;
+import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.discovery.zen.UnicastHostsProvider;
+import org.elasticsearch.discovery.zen.ZenDiscovery;
+import org.elasticsearch.plugins.DiscoveryPlugin;
+import org.elasticsearch.transport.TransportService;
+
 /**
  * A module for loading classes for node discovery.
  */
@@ -52,8 +48,7 @@ public class DiscoveryModule extends AbstractModule {
         new Setting<>("discovery.zen.hosts_provider", DISCOVERY_TYPE_SETTING, Function.identity(), Property.NodeScope);
 
     private final Settings settings;
-    private final Map<String, Supplier<UnicastHostsProvider>> unicastHostProviders;
-    private final ExtensionPoint.ClassSet<ZenPing> zenPings = new ExtensionPoint.ClassSet<>("zen_ping", ZenPing.class);
+    private final UnicastHostsProvider hostsProvider;
     private final Map<String, Class<? extends Discovery>> discoveryTypes = new HashMap<>();
 
     public DiscoveryModule(Settings settings, TransportService transportService, NetworkService networkService,
@@ -62,16 +57,30 @@ public class DiscoveryModule extends AbstractModule {
         addDiscoveryType("none", NoneDiscovery.class);
         addDiscoveryType("zen", ZenDiscovery.class);
 
-        Map<String, Supplier<UnicastHostsProvider>> hostProviders = new HashMap<>();
-        hostProviders.put("zen", () -> Collections::emptyList);
-        for (DiscoveryPlugin plugin : plugins) {
-            plugin.getZenHostsProviders(transportService, networkService).entrySet().forEach(entry -> {
-                if (hostProviders.put(entry.getKey(), entry.getValue()) != null) {
-                    throw new IllegalArgumentException("Cannot specify zen hosts provider [" + entry.getKey() + "] twice");
-                }
-            });
+        String discoveryType = DISCOVERY_TYPE_SETTING.get(settings);
+        if (discoveryType.equals("none") == false) {
+            Map<String, Supplier<UnicastHostsProvider>> hostProviders = new HashMap<>();
+            hostProviders.put("zen", () -> Collections::emptyList);
+            for (DiscoveryPlugin plugin : plugins) {
+                plugin.getZenHostsProviders(transportService, networkService).entrySet().forEach(entry -> {
+                    if (hostProviders.put(entry.getKey(), entry.getValue()) != null) {
+                        throw new IllegalArgumentException("Cannot specify zen hosts provider [" + entry.getKey() + "] twice");
+                    }
+                });
+            }
+            String hostsProviderName = DISCOVERY_HOSTS_PROVIDER_SETTING.get(settings);
+            Supplier<UnicastHostsProvider> hostsProviderSupplier = hostProviders.get(hostsProviderName);
+            if (hostsProviderSupplier == null) {
+                throw new IllegalArgumentException("Unknown zen hosts provider [" + hostsProviderName + "]");
+            }
+            hostsProvider = Objects.requireNonNull(hostsProviderSupplier.get());
+        } else {
+            hostsProvider = null;
         }
-        unicastHostProviders = Collections.unmodifiableMap(hostProviders);
+    }
+
+    public UnicastHostsProvider getHostsProvider() {
+        return hostsProvider;
     }
 
     /**
@@ -84,10 +93,6 @@ public class DiscoveryModule extends AbstractModule {
         discoveryTypes.put(type, clazz);
     }
 
-    public void addZenPing(Class<? extends ZenPing> clazz) {
-        zenPings.registerExtension(clazz);
-    }
-
     @Override
     protected void configure() {
         String discoveryType = DISCOVERY_TYPE_SETTING.get(settings);
@@ -97,18 +102,7 @@ public class DiscoveryModule extends AbstractModule {
         }
 
         if (discoveryType.equals("none") == false) {
-            bind(ZenPingService.class).asEagerSingleton();
-            String hostsProviderName = DISCOVERY_HOSTS_PROVIDER_SETTING.get(settings);
-            Supplier<UnicastHostsProvider> hostsProviderSupplier = unicastHostProviders.get(hostsProviderName);
-            if (hostsProviderSupplier == null) {
-                throw new IllegalArgumentException("Unknown zen hosts provider [" + hostsProviderName + "]");
-            }
-            UnicastHostsProvider hostsProvider = Objects.requireNonNull(hostsProviderSupplier.get());
             bind(UnicastHostsProvider.class).toInstance(hostsProvider);
-            if (zenPings.isEmpty()) {
-                zenPings.registerExtension(UnicastZenPing.class);
-            }
-            zenPings.bind(binder());
         }
         bind(Discovery.class).to(discoveryClass).asEagerSingleton();
     }

core/src/main/java/org/elasticsearch/discovery/zen/FaultDetection.java

@@ -19,6 +19,8 @@
 
 package org.elasticsearch.discovery.zen;
 
+import java.io.Closeable;
+
 import org.elasticsearch.cluster.ClusterName;
 import org.elasticsearch.cluster.node.DiscoveryNode;
 import org.elasticsearch.common.component.AbstractComponent;
@@ -36,7 +38,7 @@ import static org.elasticsearch.common.unit.TimeValue.timeValueSeconds;
  * A base class for {@link MasterFaultDetection} & {@link NodesFaultDetection},
  * making sure both use the same setting.
  */
-public abstract class FaultDetection extends AbstractComponent {
+public abstract class FaultDetection extends AbstractComponent implements Closeable {
 
     public static final Setting<Boolean> CONNECT_ON_NETWORK_DISCONNECT_SETTING =
         Setting.boolSetting("discovery.zen.fd.connect_on_network_disconnect", false, Property.NodeScope);
@@ -80,6 +82,7 @@ public abstract class FaultDetection extends AbstractComponent {
         }
     }
 
+    @Override
     public void close() {
         transportService.removeConnectionListener(connectionListener);
     }

core/src/main/java/org/elasticsearch/discovery/zen/NodeJoinController.java

@@ -464,7 +464,7 @@ public class NodeJoinController extends AbstractComponent {
         }
 
         private ClusterState.Builder becomeMasterAndTrimConflictingNodes(ClusterState currentState, List<DiscoveryNode> joiningNodes) {
-            assert currentState.nodes().getMasterNodeId() == null : currentState.prettyPrint();
+            assert currentState.nodes().getMasterNodeId() == null : currentState;
             DiscoveryNodes.Builder nodesBuilder = DiscoveryNodes.builder(currentState.nodes());
             nodesBuilder.masterNodeId(currentState.nodes().getLocalNodeId());
             ClusterBlocks clusterBlocks = ClusterBlocks.builder().blocks(currentState.blocks())

core/src/main/java/org/elasticsearch/discovery/zen/UnicastZenPing.java

@@ -19,6 +19,26 @@
 
 package org.elasticsearch.discovery.zen;
 
+import java.io.Closeable;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Queue;
+import java.util.Set;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.RejectedExecutionException;
+import java.util.concurrent.ThreadFactory;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicInteger;
+import java.util.concurrent.atomic.AtomicReference;
+import java.util.function.Function;
+
 import com.carrotsearch.hppc.cursors.ObjectCursor;
 import org.apache.logging.log4j.message.ParameterizedMessage;
 import org.apache.logging.log4j.util.Supplier;
@@ -30,8 +50,7 @@ import org.elasticsearch.cluster.node.DiscoveryNode;
 import org.elasticsearch.cluster.node.DiscoveryNodes;
 import org.elasticsearch.common.Nullable;
 import org.elasticsearch.common.UUIDs;
-import org.elasticsearch.common.component.AbstractLifecycleComponent;
-import org.elasticsearch.common.inject.Inject;
+import org.elasticsearch.common.component.AbstractComponent;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.settings.Setting;
@@ -56,34 +75,13 @@ import org.elasticsearch.transport.TransportResponse;
 import org.elasticsearch.transport.TransportResponseHandler;
 import org.elasticsearch.transport.TransportService;
 
-import java.io.Closeable;
-import java.io.IOException;
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.Collection;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Map;
-import java.util.Queue;
-import java.util.Set;
-import java.util.concurrent.CopyOnWriteArrayList;
-import java.util.concurrent.CountDownLatch;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.RejectedExecutionException;
-import java.util.concurrent.ThreadFactory;
-import java.util.concurrent.TimeUnit;
-import java.util.concurrent.atomic.AtomicBoolean;
-import java.util.concurrent.atomic.AtomicInteger;
-import java.util.concurrent.atomic.AtomicReference;
-import java.util.function.Function;
-
 import static java.util.Collections.emptyList;
 import static java.util.Collections.emptyMap;
 import static java.util.Collections.emptySet;
 import static org.elasticsearch.common.util.concurrent.ConcurrentCollections.newConcurrentMap;
 import static org.elasticsearch.discovery.zen.ZenPing.PingResponse.readPingResponse;
 
-public class UnicastZenPing extends AbstractLifecycleComponent implements ZenPing {
+public class UnicastZenPing extends AbstractComponent implements ZenPing {
 
     public static final String ACTION_NAME = "internal:discovery/zen/unicast";
     public static final Setting<List<String>> DISCOVERY_ZEN_PING_UNICAST_HOSTS_SETTING =
@@ -125,15 +123,13 @@ public class UnicastZenPing extends AbstractLifecycleComponent implements ZenPin
 
     private volatile boolean closed = false;
 
-    @Inject
     public UnicastZenPing(Settings settings, ThreadPool threadPool, TransportService transportService,
-                          UnicastHostsProvider unicastHostsProviders) {
+                          UnicastHostsProvider unicastHostsProvider) {
         super(settings);
         this.threadPool = threadPool;
         this.transportService = transportService;
         this.clusterName = ClusterName.CLUSTER_NAME_SETTING.get(settings);
-
-        this.hostsProvider = unicastHostsProviders;
+        this.hostsProvider = unicastHostsProvider;
 
         this.concurrentConnects = DISCOVERY_ZEN_PING_UNICAST_CONCURRENT_CONNECTS_SETTING.get(settings);
         List<String> hosts = DISCOVERY_ZEN_PING_UNICAST_HOSTS_SETTING.get(settings);
@@ -190,26 +186,14 @@ public class UnicastZenPing extends AbstractLifecycleComponent implements ZenPin
     }
 
     @Override
-    protected void doStart() {
-    }
-
-    @Override
-    protected void doStop() {
-    }
-
-    @Override
-    protected void doClose() {
+    public void close() throws IOException {
         ThreadPool.terminate(unicastConnectExecutor, 0, TimeUnit.SECONDS);
-        try {
-            IOUtils.close(receivedResponses.values());
-        } catch (IOException e) {
-            throw new ElasticsearchException("Error wile closing send ping handlers", e);
-        }
+        IOUtils.close(receivedResponses.values());
         closed = true;
     }
 
     @Override
-    public void setPingContextProvider(PingContextProvider contextProvider) {
+    public void start(PingContextProvider contextProvider) {
         this.contextProvider = contextProvider;
     }
 
@@ -501,9 +485,6 @@ public class UnicastZenPing extends AbstractLifecycleComponent implements ZenPin
     }
 
     private UnicastPingResponse handlePingRequest(final UnicastPingRequest request) {
-        if (!lifecycle.started()) {
-            throw new IllegalStateException("received ping request while not started");
-        }
         temporalResponses.add(request.pingResponse);
         threadPool.schedule(TimeValue.timeValueMillis(request.timeout.millis() * 2), ThreadPool.Names.SAME, new Runnable() {
             @Override

core/src/main/java/org/elasticsearch/discovery/zen/ZenDiscovery.java

@@ -22,6 +22,7 @@ package org.elasticsearch.discovery.zen;
 import org.apache.logging.log4j.Logger;
 import org.apache.logging.log4j.message.ParameterizedMessage;
 import org.apache.logging.log4j.util.Supplier;
+import org.apache.lucene.util.IOUtils;
 import org.elasticsearch.ElasticsearchException;
 import org.elasticsearch.ExceptionsHelper;
 import org.elasticsearch.cluster.ClusterChangedEvent;
@@ -67,6 +68,7 @@ import java.io.IOException;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Set;
+import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.atomic.AtomicReference;
@@ -105,7 +107,7 @@ public class ZenDiscovery extends AbstractLifecycleComponent implements Discover
     private AllocationService allocationService;
     private final ClusterName clusterName;
     private final DiscoverySettings discoverySettings;
-    private final ZenPingService pingService;
+    private final ZenPing zenPing;
     private final MasterFaultDetection masterFD;
     private final NodesFaultDetection nodesFD;
     private final PublishClusterStateAction publishClusterState;
@@ -137,18 +139,16 @@ public class ZenDiscovery extends AbstractLifecycleComponent implements Discover
     private volatile NodeRemovalClusterStateTaskExecutor nodeRemovalExecutor;
 
     @Inject
-    public ZenDiscovery(Settings settings, ThreadPool threadPool,
-                        TransportService transportService, final ClusterService clusterService, ClusterSettings clusterSettings,
-                        ZenPingService pingService) {
+    public ZenDiscovery(Settings settings, ThreadPool threadPool, TransportService transportService,
+                        ClusterService clusterService, ClusterSettings clusterSettings, ZenPing zenPing) {
         super(settings);
         this.clusterService = clusterService;
         this.clusterName = clusterService.getClusterName();
         this.transportService = transportService;
         this.discoverySettings = new DiscoverySettings(settings, clusterSettings);
-        this.pingService = pingService;
+        this.zenPing = zenPing;
         this.electMaster = new ElectMasterService(settings);
         this.pingTimeout = PING_TIMEOUT_SETTING.get(settings);
-
         this.joinTimeout = JOIN_TIMEOUT_SETTING.get(settings);
         this.joinRetryAttempts = JOIN_RETRY_ATTEMPTS_SETTING.get(settings);
         this.joinRetryDelay = JOIN_RETRY_DELAY_SETTING.get(settings);
@@ -171,7 +171,6 @@ public class ZenDiscovery extends AbstractLifecycleComponent implements Discover
 
         this.masterFD = new MasterFaultDetection(settings, threadPool, transportService, clusterService);
         this.masterFD.addListener(new MasterNodeFailureListener());
-
         this.nodesFD = new NodesFaultDetection(settings, threadPool, transportService, clusterService.getClusterName());
         this.nodesFD.addListener(new NodeFaultDetectionListener());
 
@@ -183,9 +182,7 @@ public class ZenDiscovery extends AbstractLifecycleComponent implements Discover
                         new NewPendingClusterStateListener(),
                         discoverySettings,
                         clusterService.getClusterName());
-        this.pingService.setPingContextProvider(this);
         this.membership = new MembershipAction(settings, transportService, this, new MembershipListener());
-
         this.joinThreadControl = new JoinThreadControl(threadPool);
 
         transportService.registerRequestHandler(
@@ -201,7 +198,7 @@ public class ZenDiscovery extends AbstractLifecycleComponent implements Discover
     protected void doStart() {
         nodesFD.setLocalNode(clusterService.localNode());
         joinThreadControl.start();
-        pingService.start();
+        zenPing.start(this);
         this.nodeJoinController = new NodeJoinController(clusterService, allocationService, electMaster, discoverySettings, settings);
         this.nodeRemovalExecutor = new NodeRemovalClusterStateTaskExecutor(allocationService, electMaster, this::rejoin, logger);
     }
@@ -233,7 +230,6 @@ public class ZenDiscovery extends AbstractLifecycleComponent implements Discover
     @Override
     protected void doStop() {
         joinThreadControl.stop();
-        pingService.stop();
         masterFD.stop("zen disco stop");
         nodesFD.stop();
         DiscoveryNodes nodes = nodes();
@@ -264,10 +260,8 @@ public class ZenDiscovery extends AbstractLifecycleComponent implements Discover
     }
 
     @Override
-    protected void doClose() {
-        masterFD.close();
-        nodesFD.close();
-        pingService.close();
+    protected void doClose() throws IOException {
+        IOUtils.close(masterFD, nodesFD, zenPing);
     }
 
     @Override
@@ -322,6 +316,11 @@ public class ZenDiscovery extends AbstractLifecycleComponent implements Discover
 
         // update the set of nodes to ping after the new cluster state has been published
         nodesFD.updateNodesAndPing(clusterChangedEvent.state());
+
+        // clean the pending cluster queue - we are currently master, so any pending cluster state should be failed
+        // note that we also clean the queue on master failure (see handleMasterGone) but a delayed cluster state publish
+        // from a stale master can still make it in the queue during the election (but not be committed)
+        publishClusterState.pendingStatesQueue().failAllStatesAndClear(new ElasticsearchException("elected as master"));
     }
 
     /**
@@ -362,6 +361,10 @@ public class ZenDiscovery extends AbstractLifecycleComponent implements Discover
         return publishClusterState.pendingStatesQueue().pendingClusterStates();
     }
 
+    PendingClusterStatesQueue pendingClusterStatesQueue() {
+        return publishClusterState.pendingStatesQueue();
+    }
+
     /**
      * the main function of a join thread. This function is guaranteed to join the cluster
      * or spawn a new join thread upon failure to do so.
@@ -862,7 +865,7 @@ public class ZenDiscovery extends AbstractLifecycleComponent implements Discover
 
     private DiscoveryNode findMaster() {
         logger.trace("starting to ping");
-        List<ZenPing.PingResponse> fullPingResponses = pingService.pingAndWait(pingTimeout).toList();
+        List<ZenPing.PingResponse> fullPingResponses = pingAndWait(pingTimeout).toList();
         if (fullPingResponses == null) {
             logger.trace("No full ping responses");
             return null;
@@ -1004,6 +1007,28 @@ public class ZenDiscovery extends AbstractLifecycleComponent implements Discover
         }
     }
 
+    private ZenPing.PingCollection pingAndWait(TimeValue timeout) {
+        final ZenPing.PingCollection response = new ZenPing.PingCollection();
+        final CountDownLatch latch = new CountDownLatch(1);
+        try {
+            zenPing.ping(pings -> {
+                response.addPings(pings);
+                latch.countDown();
+            }, timeout);
+        } catch (Exception ex) {
+            logger.warn("Ping execution failed", ex);
+            latch.countDown();
+        }
+
+        try {
+            latch.await();
+            return response;
+        } catch (InterruptedException e) {
+            logger.trace("pingAndWait interrupted");
+            return response;
+        }
+    }
+
     private class NewPendingClusterStateListener implements PublishClusterStateAction.NewPendingClusterStateListener {
 
         @Override

core/src/main/java/org/elasticsearch/discovery/zen/ZenPing.java

@@ -19,15 +19,7 @@
 
 package org.elasticsearch.discovery.zen;
 
-import org.elasticsearch.cluster.ClusterName;
-import org.elasticsearch.cluster.ClusterState;
-import org.elasticsearch.cluster.node.DiscoveryNode;
-import org.elasticsearch.common.component.LifecycleComponent;
-import org.elasticsearch.common.io.stream.StreamInput;
-import org.elasticsearch.common.io.stream.StreamOutput;
-import org.elasticsearch.common.io.stream.Streamable;
-import org.elasticsearch.common.unit.TimeValue;
-
+import java.io.Closeable;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Collection;
@@ -36,11 +28,19 @@ import java.util.List;
 import java.util.Map;
 import java.util.concurrent.atomic.AtomicLong;
 
+import org.elasticsearch.cluster.ClusterName;
+import org.elasticsearch.cluster.ClusterState;
+import org.elasticsearch.cluster.node.DiscoveryNode;
+import org.elasticsearch.common.io.stream.StreamInput;
+import org.elasticsearch.common.io.stream.StreamOutput;
+import org.elasticsearch.common.io.stream.Streamable;
+import org.elasticsearch.common.unit.TimeValue;
+
 import static org.elasticsearch.gateway.GatewayService.STATE_NOT_RECOVERED_BLOCK;
 
-public interface ZenPing extends LifecycleComponent {
+public interface ZenPing extends Closeable {
 
-    void setPingContextProvider(PingContextProvider contextProvider);
+    void start(PingContextProvider contextProvider);
 
     void ping(PingListener listener, TimeValue timeout);
 

core/src/main/java/org/elasticsearch/discovery/zen/ZenPingService.java

@@ -1,105 +0,0 @@
-/*
- * Licensed to Elasticsearch under one or more contributor
- * license agreements. See the NOTICE file distributed with
- * this work for additional information regarding copyright
- * ownership. Elasticsearch licenses this file to you under
- * the Apache License, Version 2.0 (the "License"); you may
- * not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *    http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing,
- * software distributed under the License is distributed on an
- * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
- * KIND, either express or implied.  See the License for the
- * specific language governing permissions and limitations
- * under the License.
- */
-
-package org.elasticsearch.discovery.zen;
-
-import org.elasticsearch.common.component.AbstractLifecycleComponent;
-import org.elasticsearch.common.inject.Inject;
-import org.elasticsearch.common.settings.Settings;
-import org.elasticsearch.common.unit.TimeValue;
-
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.List;
-import java.util.Set;
-import java.util.concurrent.CountDownLatch;
-import java.util.concurrent.atomic.AtomicBoolean;
-
-public class ZenPingService extends AbstractLifecycleComponent {
-
-    private List<ZenPing> zenPings = Collections.emptyList();
-
-    @Inject
-    public ZenPingService(Settings settings, Set<ZenPing> zenPings) {
-        super(settings);
-        this.zenPings = Collections.unmodifiableList(new ArrayList<>(zenPings));
-    }
-
-    public List<ZenPing> zenPings() {
-        return this.zenPings;
-    }
-
-    public void setPingContextProvider(PingContextProvider contextProvider) {
-        if (lifecycle.started()) {
-            throw new IllegalStateException("Can't set nodes provider when started");
-        }
-        for (ZenPing zenPing : zenPings) {
-            zenPing.setPingContextProvider(contextProvider);
-        }
-    }
-
-    @Override
-    protected void doStart() {
-        for (ZenPing zenPing : zenPings) {
-            zenPing.start();
-        }
-    }
-
-    @Override
-    protected void doStop() {
-        for (ZenPing zenPing : zenPings) {
-            zenPing.stop();
-        }
-    }
-
-    @Override
-    protected void doClose() {
-        for (ZenPing zenPing : zenPings) {
-            zenPing.close();
-        }
-    }
-
-    public ZenPing.PingCollection pingAndWait(TimeValue timeout) {
-        final ZenPing.PingCollection response = new ZenPing.PingCollection();
-        final CountDownLatch latch = new CountDownLatch(zenPings.size());
-        for (ZenPing zenPing : zenPings) {
-            final AtomicBoolean counted = new AtomicBoolean();
-            try {
-                zenPing.ping(pings -> {
-                    response.addPings(pings);
-                    if (counted.compareAndSet(false, true)) {
-                        latch.countDown();
-                    }
-                }, timeout);
-            } catch (Exception ex) {
-                logger.warn("Ping execution failed", ex);
-                if (counted.compareAndSet(false, true)) {
-                    latch.countDown();
-                }
-            }
-        }
-        try {
-            latch.await();
-            return response;
-        } catch (InterruptedException e) {
-            logger.trace("pingAndWait interrupted");
-            return response;
-        }
-    }
-}

core/src/main/java/org/elasticsearch/index/IndexService.java

@@ -52,6 +52,7 @@ import org.elasticsearch.index.query.QueryShardContext;
 import org.elasticsearch.index.shard.IndexEventListener;
 import org.elasticsearch.index.shard.IndexSearcherWrapper;
 import org.elasticsearch.index.shard.IndexShard;
+import org.elasticsearch.index.shard.IndexShardClosedException;
 import org.elasticsearch.index.shard.IndexingOperationListener;
 import org.elasticsearch.index.shard.SearchOperationListener;
 import org.elasticsearch.index.shard.ShadowIndexShard;
@@ -144,7 +145,10 @@ public class IndexService extends AbstractIndexComponent implements IndicesClust
         this.indexAnalyzers = registry.build(indexSettings);
         this.similarityService = similarityService;
         this.mapperService = new MapperService(indexSettings, indexAnalyzers, similarityService, mapperRegistry,
-            IndexService.this::newQueryShardContext);
+            // we parse all percolator queries as they would be parsed on shard 0
+            () -> newQueryShardContext(0, null, () -> {
+                throw new IllegalArgumentException("Percolator queries are not allowed to use the curent timestamp");
+            }));
         this.indexFieldData = new IndexFieldDataService(indexSettings, indicesFieldDataCache, circuitBreakerService, mapperService);
         this.shardStoreDeleter = shardStoreDeleter;
         this.bigArrays = bigArrays;
@@ -452,7 +456,10 @@ public class IndexService extends AbstractIndexComponent implements IndicesClust
 
     /**
      * Creates a new QueryShardContext. The context has not types set yet, if types are required set them via
-     * {@link QueryShardContext#setTypes(String...)}
+     * {@link QueryShardContext#setTypes(String...)}.
+     *
+     * Passing a {@code null} {@link IndexReader} will return a valid context, however it won't be able to make
+     * {@link IndexReader}-specific optimizations, such as rewriting containing range queries.
      */
     public QueryShardContext newQueryShardContext(int shardId, IndexReader indexReader, LongSupplier nowInMillis) {
         return new QueryShardContext(
@@ -463,15 +470,6 @@ public class IndexService extends AbstractIndexComponent implements IndicesClust
             nowInMillis);
     }
 
-    /**
-     * Creates a new QueryShardContext. The context has not types set yet, if types are required set them via
-     * {@link QueryShardContext#setTypes(String...)}. This context may be used for query parsing but cannot be
-     * used for rewriting since it does not know about the current {@link IndexReader}.
-     */
-    public QueryShardContext newQueryShardContext() {
-        return newQueryShardContext(0, null, System::currentTimeMillis);
-    }
-
     /**
      * The {@link ThreadPool} to use for this index.
      */
@@ -692,7 +690,7 @@ public class IndexService extends AbstractIndexComponent implements IndicesClust
                             if (shard.isRefreshNeeded()) {
                                 shard.refresh("schedule");
                             }
-                        } catch (EngineClosedException | AlreadyClosedException ex) {
+                        } catch (IndexShardClosedException | AlreadyClosedException ex) {
                             // fine - continue;
                         }
                         continue;

core/src/main/java/org/elasticsearch/index/IndexingSlowLog.java

@@ -133,23 +133,20 @@ public final class IndexingSlowLog implements IndexingOperationListener {
         this.reformat = reformat;
     }
 
-
     @Override
-    public void postIndex(Engine.Index index, boolean created) {
-        final long took = index.endTime() - index.startTime();
-        postIndexing(index.parsedDoc(), took);
-    }
-
-
-    private void postIndexing(ParsedDocument doc, long tookInNanos) {
-        if (indexWarnThreshold >= 0 && tookInNanos > indexWarnThreshold) {
-            indexLogger.warn("{}", new SlowLogParsedDocumentPrinter(index, doc, tookInNanos, reformat, maxSourceCharsToLog));
-        } else if (indexInfoThreshold >= 0 && tookInNanos > indexInfoThreshold) {
-            indexLogger.info("{}", new SlowLogParsedDocumentPrinter(index, doc, tookInNanos, reformat, maxSourceCharsToLog));
-        } else if (indexDebugThreshold >= 0 && tookInNanos > indexDebugThreshold) {
-            indexLogger.debug("{}", new SlowLogParsedDocumentPrinter(index, doc, tookInNanos, reformat, maxSourceCharsToLog));
-        } else if (indexTraceThreshold >= 0 && tookInNanos > indexTraceThreshold) {
-            indexLogger.trace("{}", new SlowLogParsedDocumentPrinter(index, doc, tookInNanos, reformat, maxSourceCharsToLog));
+    public void postIndex(Engine.Index indexOperation, Engine.IndexResult result) {
+        if (result.hasFailure() == false) {
+            final ParsedDocument doc = indexOperation.parsedDoc();
+            final long tookInNanos = result.getTook();
+            if (indexWarnThreshold >= 0 && tookInNanos > indexWarnThreshold) {
+                indexLogger.warn("{}", new SlowLogParsedDocumentPrinter(index, doc, tookInNanos, reformat, maxSourceCharsToLog));
+            } else if (indexInfoThreshold >= 0 && tookInNanos > indexInfoThreshold) {
+                indexLogger.info("{}", new SlowLogParsedDocumentPrinter(index, doc, tookInNanos, reformat, maxSourceCharsToLog));
+            } else if (indexDebugThreshold >= 0 && tookInNanos > indexDebugThreshold) {
+                indexLogger.debug("{}", new SlowLogParsedDocumentPrinter(index, doc, tookInNanos, reformat, maxSourceCharsToLog));
+            } else if (indexTraceThreshold >= 0 && tookInNanos > indexTraceThreshold) {
+                indexLogger.trace("{}", new SlowLogParsedDocumentPrinter(index, doc, tookInNanos, reformat, maxSourceCharsToLog));
+            }
         }
     }
 

core/src/main/java/org/elasticsearch/index/engine/DeleteFailedEngineException.java

@@ -24,12 +24,13 @@ import org.elasticsearch.index.shard.ShardId;
 
 import java.io.IOException;
 
+/**
+ * Deprecated as not used in 6.0, should be removed in 7.0
+ * Still exists for bwc in serializing/deserializing from
+ * 5.x nodes
+ */
+@Deprecated
 public class DeleteFailedEngineException extends EngineException {
-
-    public DeleteFailedEngineException(ShardId shardId, Engine.Delete delete, Throwable cause) {
-        super(shardId, "Delete failed for [" + delete.uid().text() + "]", cause);
-    }
-
     public DeleteFailedEngineException(StreamInput in) throws IOException{
         super(in);
     }

core/src/main/java/org/elasticsearch/index/engine/DeleteVersionValue.java

@@ -48,4 +48,12 @@ class DeleteVersionValue extends VersionValue {
     public long ramBytesUsed() {
         return BASE_RAM_BYTES_USED;
     }
+
+    @Override
+    public String toString() {
+        return "DeleteVersionValue{" +
+            "version=" + version() + ", " +
+            "time=" + time +
+            '}';
+    }
 }

core/src/main/java/org/elasticsearch/index/engine/Engine.java

@@ -77,6 +77,7 @@ import java.util.Base64;
 import java.util.Comparator;
 import java.util.HashMap;
 import java.util.List;
+import java.util.Locale;
 import java.util.Map;
 import java.util.Objects;
 import java.util.concurrent.TimeUnit;
@@ -277,9 +278,135 @@ public abstract class Engine implements Closeable {
         }
     }
 
-    public abstract void index(Index operation) throws EngineException;
+    /**
+     * Perform document index operation on the engine
+     * @param index operation to perform
+     * @return {@link IndexResult} containing updated translog location, version and
+     * document specific failures
+     *
+     * Note: engine level failures (i.e. persistent engine failures) are thrown
+     */
+    public abstract IndexResult index(final Index index);
 
-    public abstract void delete(Delete delete) throws EngineException;
+    /**
+     * Perform document delete operation on the engine
+     * @param delete operation to perform
+     * @return {@link DeleteResult} containing updated translog location, version and
+     * document specific failures
+     *
+     * Note: engine level failures (i.e. persistent engine failures) are thrown
+     */
+    public abstract DeleteResult delete(final Delete delete);
+
+    /**
+     * Base class for index and delete operation results
+     * Holds result meta data (e.g. translog location, updated version)
+     * for an executed write {@link Operation}
+     **/
+    public abstract static class Result {
+        private final Operation.TYPE operationType;
+        private final long version;
+        private final Exception failure;
+        private final SetOnce<Boolean> freeze = new SetOnce<>();
+        private Translog.Location translogLocation;
+        private long took;
+
+        protected Result(Operation.TYPE operationType, Exception failure, long version) {
+            this.operationType = operationType;
+            this.failure = failure;
+            this.version = version;
+        }
+
+        protected Result(Operation.TYPE operationType, long version) {
+            this(operationType, null, version);
+        }
+
+        /** whether the operation had failure */
+        public boolean hasFailure() {
+            return failure != null;
+        }
+
+        /** get the updated document version */
+        public long getVersion() {
+            return version;
+        }
+
+        /** get the translog location after executing the operation */
+        public Translog.Location getTranslogLocation() {
+            return translogLocation;
+        }
+
+        /** get document failure while executing the operation {@code null} in case of no failure */
+        public Exception getFailure() {
+            return failure;
+        }
+
+        /** get total time in nanoseconds */
+        public long getTook() {
+            return took;
+        }
+
+        public Operation.TYPE getOperationType() {
+            return operationType;
+        }
+
+        void setTranslogLocation(Translog.Location translogLocation) {
+            if (freeze.get() == null) {
+                assert failure == null : "failure has to be null to set translog location";
+                this.translogLocation = translogLocation;
+            } else {
+                throw new IllegalStateException("result is already frozen");
+            }
+        }
+
+        void setTook(long took) {
+            if (freeze.get() == null) {
+                this.took = took;
+            } else {
+                throw new IllegalStateException("result is already frozen");
+            }
+        }
+
+        void freeze() {
+            freeze.set(true);
+        }
+    }
+
+    public static class IndexResult extends Result {
+        private final boolean created;
+
+        public IndexResult(long version, boolean created) {
+            super(Operation.TYPE.INDEX, version);
+            this.created = created;
+        }
+
+        public IndexResult(Exception failure, long version) {
+            super(Operation.TYPE.INDEX, failure, version);
+            this.created = false;
+        }
+
+        public boolean isCreated() {
+            return created;
+        }
+    }
+
+    public static class DeleteResult extends Result {
+        private final boolean found;
+
+        public DeleteResult(long version, boolean found) {
+            super(Operation.TYPE.DELETE, version);
+            this.found = found;
+        }
+
+        public DeleteResult(Exception failure, long version) {
+            super(Operation.TYPE.DELETE, failure, version);
+            this.found = false;
+        }
+
+        public boolean isFound() {
+            return found;
+        }
+    }
 
     /**
      * Attempts to do a special commit where the given syncID is put into the commit data. The attempt
@@ -767,13 +894,27 @@ public abstract class Engine implements Closeable {
     }
 
     public abstract static class Operation {
+
+        /** type of operation (index, delete), subclasses use static types */
+        public enum TYPE {
+            INDEX, DELETE;
+
+            private final String lowercase;
+
+            TYPE() {
+                this.lowercase = this.toString().toLowerCase(Locale.ROOT);
+            }
+
+            public String getLowercase() {
+                return lowercase;
+            }
+        }
+
         private final Term uid;
-        private long version;
+        private final long version;
         private final VersionType versionType;
         private final Origin origin;
-        private Translog.Location location;
         private final long startTime;
-        private long endTime;
 
         public Operation(Term uid, long version, VersionType versionType, Origin origin, long startTime) {
             this.uid = uid;
@@ -806,27 +947,7 @@ public abstract class Engine implements Closeable {
             return this.version;
         }
 
-        public void updateVersion(long version) {
-            this.version = version;
-        }
-
-        public void setTranslogLocation(Translog.Location location) {
-            this.location = location;
-        }
-
-        public Translog.Location getTranslogLocation() {
-            return this.location;
-        }
-
-        public int sizeInBytes() {
-            if (location != null) {
-                return location.size;
-            } else {
-                return estimatedSizeInBytes();
-            }
-        }
-
-        protected abstract int estimatedSizeInBytes();
+        public abstract int estimatedSizeInBytes();
 
         public VersionType versionType() {
             return this.versionType;
@@ -839,20 +960,11 @@ public abstract class Engine implements Closeable {
             return this.startTime;
         }
 
-        public void endTime(long endTime) {
-            this.endTime = endTime;
-        }
-
-        /**
-         * Returns operation end time in nanoseconds.
-         */
-        public long endTime() {
-            return this.endTime;
-        }
-
-        abstract String type();
+        public abstract String type();
 
         abstract String id();
+
+        abstract TYPE operationType();
     }
 
     public static class Index extends Operation {
@@ -860,7 +972,6 @@ public abstract class Engine implements Closeable {
         private final ParsedDocument doc;
         private final long autoGeneratedIdTimestamp;
         private final boolean isRetry;
-        private boolean created;
 
         public Index(Term uid, ParsedDocument doc, long version, VersionType versionType, Origin origin, long startTime,
                      long autoGeneratedIdTimestamp, boolean isRetry) {
@@ -892,6 +1003,11 @@ public abstract class Engine implements Closeable {
             return this.doc.id();
         }
 
+        @Override
+        TYPE operationType() {
+            return TYPE.INDEX;
+        }
+
         public String routing() {
             return this.doc.routing();
         }
@@ -904,12 +1020,6 @@ public abstract class Engine implements Closeable {
             return this.doc.ttl();
         }
 
-        @Override
-        public void updateVersion(long version) {
-            super.updateVersion(version);
-            this.doc.version().setLongValue(version);
-        }
-
         public String parent() {
             return this.doc.parent();
         }
@@ -922,16 +1032,8 @@ public abstract class Engine implements Closeable {
             return this.doc.source();
         }
 
-        public boolean isCreated() {
-            return created;
-        }
-
-        public void setCreated(boolean created) {
-            this.created = created;
-        }
-
         @Override
-        protected int estimatedSizeInBytes() {
+        public int estimatedSizeInBytes() {
             return (id().length() + type().length()) * 2 + source().length() + 12;
         }
 
@@ -958,21 +1060,19 @@ public abstract class Engine implements Closeable {
 
         private final String type;
         private final String id;
-        private boolean found;
 
-        public Delete(String type, String id, Term uid, long version, VersionType versionType, Origin origin, long startTime, boolean found) {
+        public Delete(String type, String id, Term uid, long version, VersionType versionType, Origin origin, long startTime) {
             super(uid, version, versionType, origin, startTime);
             this.type = type;
             this.id = id;
-            this.found = found;
         }
 
         public Delete(String type, String id, Term uid) {
-            this(type, id, uid, Versions.MATCH_ANY, VersionType.INTERNAL, Origin.PRIMARY, System.nanoTime(), false);
+            this(type, id, uid, Versions.MATCH_ANY, VersionType.INTERNAL, Origin.PRIMARY, System.nanoTime());
         }
 
         public Delete(Delete template, VersionType versionType) {
-            this(template.type(), template.id(), template.uid(), template.version(), versionType, template.origin(), template.startTime(), template.found());
+            this(template.type(), template.id(), template.uid(), template.version(), versionType, template.origin(), template.startTime());
         }
 
         @Override
@@ -985,20 +1085,15 @@ public abstract class Engine implements Closeable {
             return this.id;
         }
 
-        public void updateVersion(long version, boolean found) {
-            updateVersion(version);
-            this.found = found;
-        }
-
-        public boolean found() {
-            return this.found;
+        @Override
+        TYPE operationType() {
+            return TYPE.DELETE;
         }
 
         @Override
-        protected int estimatedSizeInBytes() {
+        public int estimatedSizeInBytes() {
             return (uid().field().length() + uid().text().length()) * 2 + 20;
         }
-
     }
 
     public static class Get {

core/src/main/java/org/elasticsearch/index/engine/IndexFailedEngineException.java

@@ -26,20 +26,18 @@ import org.elasticsearch.index.shard.ShardId;
 import java.io.IOException;
 import java.util.Objects;
 
+/**
+ * Deprecated as not used in 6.0, should be removed in 7.0
+ * Still exists for bwc in serializing/deserializing from
+ * 5.x nodes
+ */
+@Deprecated
 public class IndexFailedEngineException extends EngineException {
 
     private final String type;
 
     private final String id;
 
-    public IndexFailedEngineException(ShardId shardId, String type, String id, Throwable cause) {
-        super(shardId, "Index failed for [" + type + "#" + id + "]", cause);
-        Objects.requireNonNull(type, "type must not be null");
-        Objects.requireNonNull(id, "id must not be null");
-        this.type = type;
-        this.id = id;
-    }
-
     public IndexFailedEngineException(StreamInput in) throws IOException{
         super(in);
         type = in.readString();

core/src/main/java/org/elasticsearch/index/engine/InternalEngine.java

@@ -35,6 +35,7 @@ import org.apache.lucene.index.Term;
 import org.apache.lucene.search.IndexSearcher;
 import org.apache.lucene.search.SearcherFactory;
 import org.apache.lucene.search.SearcherManager;
+import org.apache.lucene.search.TermQuery;
 import org.apache.lucene.store.AlreadyClosedException;
 import org.apache.lucene.store.Directory;
 import org.apache.lucene.store.LockObtainFailedException;
@@ -57,6 +58,7 @@ import org.elasticsearch.common.util.concurrent.KeyedLock;
 import org.elasticsearch.common.util.concurrent.ReleasableLock;
 import org.elasticsearch.index.IndexSettings;
 import org.elasticsearch.index.VersionType;
+import org.elasticsearch.index.mapper.ParseContext;
 import org.elasticsearch.index.mapper.Uid;
 import org.elasticsearch.index.merge.MergeStats;
 import org.elasticsearch.index.merge.OnGoingMerge;
@@ -386,46 +388,61 @@ public class InternalEngine extends Engine {
         return currentVersion;
     }
 
-    private static VersionValueSupplier NEW_VERSION_VALUE = (u, t) -> new VersionValue(u);
-
-    @FunctionalInterface
-    private interface VersionValueSupplier {
-        VersionValue apply(long updatedVersion, long time);
-    }
-
-    private <T extends Engine.Operation> void maybeAddToTranslog(
-            final T op,
-            final long updatedVersion,
-            final Function<T, Translog.Operation> toTranslogOp,
-            final VersionValueSupplier toVersionValue) throws IOException {
-        if (op.origin() != Operation.Origin.LOCAL_TRANSLOG_RECOVERY) {
-            final Translog.Location translogLocation = translog.add(toTranslogOp.apply(op));
-            op.setTranslogLocation(translogLocation);
-        }
-        versionMap.putUnderLock(op.uid().bytes(), toVersionValue.apply(updatedVersion, engineConfig.getThreadPool().estimatedTimeInMillis()));
-
-    }
-
     @Override
-    public void index(Index index) {
+    public IndexResult index(Index index) {
+        IndexResult result;
         try (ReleasableLock lock = readLock.acquire()) {
             ensureOpen();
             if (index.origin().isRecovery()) {
                 // Don't throttle recovery operations
-                innerIndex(index);
+                result = innerIndex(index);
             } else {
                 try (Releasable r = throttle.acquireThrottle()) {
-                    innerIndex(index);
+                    result = innerIndex(index);
                 }
             }
-        } catch (IllegalStateException | IOException e) {
-            try {
-                maybeFailEngine("index", e);
-            } catch (Exception inner) {
-                e.addSuppressed(inner);
-            }
-            throw new IndexFailedEngineException(shardId, index.type(), index.id(), e);
+        } catch (Exception e) {
+            result = new IndexResult(checkIfDocumentFailureOrThrow(index, e), index.version());
         }
+        return result;
+    }
+
+    /**
+     * Inspects exception thrown when executing index or delete operations
+     *
+     * @return failure if the failure is a document specific failure (e.g. analysis chain failure)
+     * or throws Exception if the failure caused the engine to fail (e.g. out of disk, lucene tragic event)
+     *
+     * Note: pkg-private for testing
+     */
+    final Exception checkIfDocumentFailureOrThrow(final Operation operation, final Exception failure) {
+        boolean isDocumentFailure;
+        try {
+            // When indexing a document into Lucene, Lucene distinguishes between environment related errors
+            // (like out of disk space) and document specific errors (like analysis chain problems) by setting
+            // the IndexWriter.getTragicEvent() value for the former. maybeFailEngine checks for these kind of
+            // errors and returns true if that is the case. We use that to indicate a document level failure
+            // and set the error in operation.setFailure. In case of environment related errors, the failure
+            // is bubbled up
+            isDocumentFailure = maybeFailEngine(operation.operationType().getLowercase(), failure) == false;
+        } catch (Exception inner) {
+            // we failed checking whether the failure can fail the engine, treat it as a persistent engine failure
+            isDocumentFailure = false;
+            failure.addSuppressed(inner);
+        }
+        if (isDocumentFailure) {
+            return failure;
+        } else {
+            // throw original exception in case the exception caused the engine to fail
+            rethrow(failure);
+            return null;
+        }
+    }
+
+    // hack to rethrow original exception in case of engine level failures during index/delete operation
+    @SuppressWarnings("unchecked")
+    private static <T extends Throwable> void rethrow(Throwable t) throws T {
+        throw (T) t;
     }
 
     private boolean canOptimizeAddDocument(Index index) {
@@ -452,7 +469,9 @@ public class InternalEngine extends Engine {
         return false;
     }
 
-    private void innerIndex(Index index) throws IOException {
+    private IndexResult innerIndex(Index index) throws IOException {
+        final Translog.Location location;
+        final long updatedVersion;
         try (Releasable ignored = acquireLock(index.uid())) {
             lastWriteNanos = index.startTime();
             /* if we have an autoGeneratedID that comes into the engine we can potentially optimize
@@ -484,7 +503,8 @@ public class InternalEngine extends Engine {
             // if anything is fishy here ie. there is a retry we go and force updateDocument below so we are updating the document in the
             // lucene index without checking the version map but we still do the version check
             final boolean forceUpdateDocument;
-            if (canOptimizeAddDocument(index)) {
+            final boolean canOptimizeAddDocument = canOptimizeAddDocument(index);
+            if (canOptimizeAddDocument) {
                 long deOptimizeTimestamp = maxUnsafeAutoIdTimestamp.get();
                 if (index.isRetry()) {
                     forceUpdateDocument = true;
@@ -516,60 +536,81 @@ public class InternalEngine extends Engine {
                 }
             }
             final long expectedVersion = index.version();
+            final IndexResult indexResult;
             if (checkVersionConflict(index, currentVersion, expectedVersion, deleted)) {
-                index.setCreated(false);
-                return;
-            }
-            final long updatedVersion = updateVersion(index, currentVersion, expectedVersion);
-            index.setCreated(deleted);
-            if (currentVersion == Versions.NOT_FOUND && forceUpdateDocument == false) {
-                // document does not exists, we can optimize for create
-                index(index, indexWriter);
+                // skip index operation because of version conflict on recovery
+                indexResult = new IndexResult(expectedVersion, false);
             } else {
-                update(index, indexWriter);
+                updatedVersion = index.versionType().updateVersion(currentVersion, expectedVersion);
+                index.parsedDoc().version().setLongValue(updatedVersion);
+                if (currentVersion == Versions.NOT_FOUND && forceUpdateDocument == false) {
+                    // document does not exists, we can optimize for create, but double check if assertions are running
+                    assert assertDocDoesNotExist(index, canOptimizeAddDocument == false);
+                    index(index.docs(), indexWriter);
+                } else {
+                    update(index.uid(), index.docs(), indexWriter);
+                }
+                indexResult = new IndexResult(updatedVersion, deleted);
+                location = index.origin() != Operation.Origin.LOCAL_TRANSLOG_RECOVERY
+                        ? translog.add(new Translog.Index(index, indexResult))
+                        : null;
+                versionMap.putUnderLock(index.uid().bytes(), new VersionValue(updatedVersion));
+                indexResult.setTranslogLocation(location);
             }
-            maybeAddToTranslog(index, updatedVersion, Translog.Index::new, NEW_VERSION_VALUE);
+            indexResult.setTook(System.nanoTime() - index.startTime());
+            indexResult.freeze();
+            return indexResult;
         }
     }
 
-    private long updateVersion(Engine.Operation op, long currentVersion, long expectedVersion) {
-        final long updatedVersion = op.versionType().updateVersion(currentVersion, expectedVersion);
-        op.updateVersion(updatedVersion);
-        return updatedVersion;
-    }
-
-    private static void index(final Index index, final IndexWriter indexWriter) throws IOException {
-        if (index.docs().size() > 1) {
-            indexWriter.addDocuments(index.docs());
+    private static void index(final List<ParseContext.Document> docs, final IndexWriter indexWriter) throws IOException {
+        if (docs.size() > 1) {
+            indexWriter.addDocuments(docs);
         } else {
-            indexWriter.addDocument(index.docs().get(0));
+            indexWriter.addDocument(docs.get(0));
         }
     }
 
-    private static void update(final Index index, final IndexWriter indexWriter) throws IOException {
-        if (index.docs().size() > 1) {
-            indexWriter.updateDocuments(index.uid(), index.docs());
+    /**
+     * Asserts that the doc in the index operation really doesn't exist
+     */
+    private boolean assertDocDoesNotExist(final Index index, final boolean allowDeleted) throws IOException {
+        final VersionValue versionValue = versionMap.getUnderLock(index.uid());
+        if (versionValue != null) {
+            if (versionValue.delete() == false || allowDeleted == false) {
+                throw new AssertionError("doc [" + index.type() + "][" + index.id() + "] exists in version map (version " + versionValue + ")");
+            }
         } else {
-            indexWriter.updateDocument(index.uid(), index.docs().get(0));
+            try (final Searcher searcher = acquireSearcher("assert doc doesn't exist")) {
+                final long docsWithId = searcher.searcher().count(new TermQuery(index.uid()));
+                if (docsWithId > 0) {
+                    throw new AssertionError("doc [" + index.type() + "][" + index.id() + "] exists [" + docsWithId + "] times in index");
+                }
+            }
+        }
+        return true;
+    }
+
+    private static void update(final Term uid, final List<ParseContext.Document> docs, final IndexWriter indexWriter) throws IOException {
+        if (docs.size() > 1) {
+            indexWriter.updateDocuments(uid, docs);
+        } else {
+            indexWriter.updateDocument(uid, docs.get(0));
         }
     }
 
     @Override
-    public void delete(Delete delete) throws EngineException {
+    public DeleteResult delete(Delete delete) {
+        DeleteResult result;
         try (ReleasableLock lock = readLock.acquire()) {
             ensureOpen();
             // NOTE: we don't throttle this when merges fall behind because delete-by-id does not create new segments:
-            innerDelete(delete);
-        } catch (IllegalStateException | IOException e) {
-            try {
-                maybeFailEngine("delete", e);
-            } catch (Exception inner) {
-                e.addSuppressed(inner);
-            }
-            throw new DeleteFailedEngineException(shardId, delete, e);
+            result = innerDelete(delete);
+        } catch (Exception e) {
+            result = new DeleteResult(checkIfDocumentFailureOrThrow(delete, e), delete.version());
         }
-
         maybePruneDeletedTombstones();
+        return result;
     }
 
     private void maybePruneDeletedTombstones() {
@@ -580,7 +621,10 @@ public class InternalEngine extends Engine {
         }
     }
 
-    private void innerDelete(Delete delete) throws IOException {
+    private DeleteResult innerDelete(Delete delete) throws IOException {
+        final Translog.Location location;
+        final long updatedVersion;
+        final boolean found;
         try (Releasable ignored = acquireLock(delete.uid())) {
             lastWriteNanos = delete.startTime();
             final long currentVersion;
@@ -596,19 +640,28 @@ public class InternalEngine extends Engine {
             }
 
             final long expectedVersion = delete.version();
-            if (checkVersionConflict(delete, currentVersion, expectedVersion, deleted)) return;
-
-            final long updatedVersion = updateVersion(delete, currentVersion, expectedVersion);
-
-            final boolean found = deleteIfFound(delete, currentVersion, deleted, versionValue);
-
-            delete.updateVersion(updatedVersion, found);
-
-            maybeAddToTranslog(delete, updatedVersion, Translog.Delete::new, DeleteVersionValue::new);
+            final DeleteResult deleteResult;
+            if (checkVersionConflict(delete, currentVersion, expectedVersion, deleted)) {
+                // skip executing delete because of version conflict on recovery
+                deleteResult = new DeleteResult(expectedVersion, true);
+            } else {
+                updatedVersion = delete.versionType().updateVersion(currentVersion, expectedVersion);
+                found = deleteIfFound(delete.uid(), currentVersion, deleted, versionValue);
+                deleteResult = new DeleteResult(updatedVersion, found);
+                location = delete.origin() != Operation.Origin.LOCAL_TRANSLOG_RECOVERY
+                        ? translog.add(new Translog.Delete(delete, deleteResult))
+                        : null;
+                versionMap.putUnderLock(delete.uid().bytes(),
+                        new DeleteVersionValue(updatedVersion, engineConfig.getThreadPool().estimatedTimeInMillis()));
+                deleteResult.setTranslogLocation(location);
+            }
+            deleteResult.setTook(System.nanoTime() - delete.startTime());
+            deleteResult.freeze();
+            return deleteResult;
         }
     }
 
-    private boolean deleteIfFound(Delete delete, long currentVersion, boolean deleted, VersionValue versionValue) throws IOException {
+    private boolean deleteIfFound(Term uid, long currentVersion, boolean deleted, VersionValue versionValue) throws IOException {
         final boolean found;
         if (currentVersion == Versions.NOT_FOUND) {
             // doc does not exist and no prior deletes
@@ -618,7 +671,7 @@ public class InternalEngine extends Engine {
             found = false;
         } else {
             // we deleted a currently existing document
-            indexWriter.deleteDocuments(delete.uid());
+            indexWriter.deleteDocuments(uid);
             found = true;
         }
         return found;
@@ -1086,7 +1139,8 @@ public class InternalEngine extends Engine {
         }
     }
 
-    private IndexWriter createWriter(boolean create) throws IOException {
+    // pkg-private for testing
+    IndexWriter createWriter(boolean create) throws IOException {
         try {
             final IndexWriterConfig iwc = new IndexWriterConfig(engineConfig.getAnalyzer());
             iwc.setCommitOnClose(false); // we by default don't commit on close

core/src/main/java/org/elasticsearch/index/engine/ShadowEngine.java

@@ -106,12 +106,12 @@ public class ShadowEngine extends Engine {
 
 
     @Override
-    public void index(Index index) throws EngineException {
+    public IndexResult index(Index index) {
         throw new UnsupportedOperationException(shardId + " index operation not allowed on shadow engine");
     }
 
     @Override
-    public void delete(Delete delete) throws EngineException {
+    public DeleteResult delete(Delete delete) {
         throw new UnsupportedOperationException(shardId + " delete operation not allowed on shadow engine");
     }
 

core/src/main/java/org/elasticsearch/index/engine/VersionValue.java

@@ -57,4 +57,11 @@ class VersionValue implements Accountable {
     public Collection<Accountable> getChildResources() {
         return Collections.emptyList();
     }
+
+    @Override
+    public String toString() {
+        return "VersionValue{" +
+            "version=" + version +
+            '}';
+    }
 }

core/src/main/java/org/elasticsearch/index/mapper/DocumentMapperParser.java

@@ -69,7 +69,7 @@ public class DocumentMapperParser {
     }
 
     public Mapper.TypeParser.ParserContext parserContext(String type) {
-        return new Mapper.TypeParser.ParserContext(type, indexAnalyzers, similarityService::getSimilarity, mapperService, typeParsers::get, indexVersionCreated, parseFieldMatcher, queryShardContextSupplier.get());
+        return new Mapper.TypeParser.ParserContext(type, indexAnalyzers, similarityService::getSimilarity, mapperService, typeParsers::get, indexVersionCreated, parseFieldMatcher, queryShardContextSupplier);
     }
 
     public DocumentMapper parse(@Nullable String type, CompressedXContent source) throws MapperParsingException {

core/src/main/java/org/elasticsearch/index/mapper/Mapper.java

@@ -20,7 +20,6 @@
 package org.elasticsearch.index.mapper;
 
 import org.elasticsearch.Version;
-import org.elasticsearch.common.Nullable;
 import org.elasticsearch.common.ParseFieldMatcher;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.xcontent.ToXContent;
@@ -31,6 +30,7 @@ import org.elasticsearch.index.similarity.SimilarityProvider;
 import java.util.Map;
 import java.util.Objects;
 import java.util.function.Function;
+import java.util.function.Supplier;
 
 public abstract class Mapper implements ToXContent, Iterable<Mapper> {
 
@@ -93,11 +93,13 @@ public abstract class Mapper implements ToXContent, Iterable<Mapper> {
 
             private final ParseFieldMatcher parseFieldMatcher;
 
-            private final QueryShardContext queryShardContext;
+            private final Supplier<QueryShardContext> queryShardContextSupplier;
+            private QueryShardContext queryShardContext;
 
             public ParserContext(String type, IndexAnalyzers indexAnalyzers, Function<String, SimilarityProvider> similarityLookupService,
                                  MapperService mapperService, Function<String, TypeParser> typeParsers,
-                                 Version indexVersionCreated, ParseFieldMatcher parseFieldMatcher, QueryShardContext queryShardContext) {
+                                 Version indexVersionCreated, ParseFieldMatcher parseFieldMatcher,
+                                 Supplier<QueryShardContext> queryShardContextSupplier) {
                 this.type = type;
                 this.indexAnalyzers = indexAnalyzers;
                 this.similarityLookupService = similarityLookupService;
@@ -105,7 +107,7 @@ public abstract class Mapper implements ToXContent, Iterable<Mapper> {
                 this.typeParsers = typeParsers;
                 this.indexVersionCreated = indexVersionCreated;
                 this.parseFieldMatcher = parseFieldMatcher;
-                this.queryShardContext = queryShardContext;
+                this.queryShardContextSupplier = queryShardContextSupplier;
             }
 
             public String type() {
@@ -137,6 +139,10 @@ public abstract class Mapper implements ToXContent, Iterable<Mapper> {
             }
 
             public QueryShardContext queryShardContext() {
+                // No need for synchronization, this class must be used in a single thread
+                if (queryShardContext == null) {
+                    queryShardContext = queryShardContextSupplier.get();
+                }
                 return queryShardContext;
             }
 
@@ -155,7 +161,7 @@ public abstract class Mapper implements ToXContent, Iterable<Mapper> {
 
             static class MultiFieldParserContext extends ParserContext {
                 MultiFieldParserContext(ParserContext in) {
-                    super(in.type(), in.indexAnalyzers, in.similarityLookupService(), in.mapperService(), in.typeParsers(), in.indexVersionCreated(), in.parseFieldMatcher(), in.queryShardContext());
+                    super(in.type(), in.indexAnalyzers, in.similarityLookupService(), in.mapperService(), in.typeParsers(), in.indexVersionCreated(), in.parseFieldMatcher(), in::queryShardContext);
                 }
             }
 

core/src/main/java/org/elasticsearch/index/mapper/MapperService.java

@@ -54,7 +54,6 @@ import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.function.Function;
-import java.util.function.LongSupplier;
 import java.util.function.Supplier;
 import java.util.stream.Collectors;
 

core/src/main/java/org/elasticsearch/index/query/FuzzyQueryBuilder.java

@@ -28,6 +28,8 @@ import org.elasticsearch.common.ParsingException;
 import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
+import org.elasticsearch.common.logging.DeprecationLogger;
+import org.elasticsearch.common.logging.Loggers;
 import org.elasticsearch.common.lucene.BytesRefs;
 import org.elasticsearch.common.unit.Fuzziness;
 import org.elasticsearch.common.xcontent.XContentBuilder;
@@ -49,6 +51,8 @@ import java.util.Optional;
 public class FuzzyQueryBuilder extends AbstractQueryBuilder<FuzzyQueryBuilder> implements MultiTermQueryBuilder {
     public static final String NAME = "fuzzy";
 
+    private static final DeprecationLogger DEPRECATION_LOGGER = new DeprecationLogger(Loggers.getLogger(FuzzyQueryBuilder.class));
+
     /** Default maximum edit distance. Defaults to AUTO. */
     public static final Fuzziness DEFAULT_FUZZINESS = Fuzziness.AUTO;
 
@@ -151,6 +155,7 @@ public class FuzzyQueryBuilder extends AbstractQueryBuilder<FuzzyQueryBuilder> i
      * @param value The value of the term
      */
     public FuzzyQueryBuilder(String fieldName, Object value) {
+        DEPRECATION_LOGGER.deprecated("{} query is deprecated. Instead use the [match] query with fuzziness parameter", NAME);
         if (Strings.isEmpty(fieldName)) {
             throw new IllegalArgumentException("field name cannot be null or empty");
         }

core/src/main/java/org/elasticsearch/index/query/QueryRewriteContext.java

@@ -67,7 +67,7 @@ public class QueryRewriteContext implements ParseFieldMatcherSupplier {
     /**
      * Returns a clients to fetch resources from local or remove nodes.
      */
-    public final Client getClient() {
+    public Client getClient() {
         return client;
     }
 
@@ -86,7 +86,9 @@ public class QueryRewriteContext implements ParseFieldMatcherSupplier {
         return mapperService;
     }
 
-    /** Return the current {@link IndexReader}, or {@code null} if we are on the coordinating node. */
+    /** Return the current {@link IndexReader}, or {@code null} if no index reader is available, for
+     *  instance if we are on the coordinating node or if this rewrite context is used to index
+     *  queries (percolation). */
     public IndexReader getIndexReader() {
         return reader;
     }

core/src/main/java/org/elasticsearch/index/query/QueryShardContext.java

@@ -421,4 +421,9 @@ public class QueryShardContext extends QueryRewriteContext {
         return super.nowInMillis();
     }
 
+    @Override
+    public Client getClient() {
+        failIfFrozen(); // we somebody uses a terms filter with lookup for instance can't be cached...
+        return super.getClient();
+    }
 }

core/src/main/java/org/elasticsearch/index/query/QueryStringQueryBuilder.java

@@ -26,6 +26,7 @@ import org.apache.lucene.search.BoostQuery;
 import org.apache.lucene.search.FuzzyQuery;
 import org.apache.lucene.search.Query;
 import org.apache.lucene.util.automaton.Operations;
+import org.elasticsearch.Version;
 import org.elasticsearch.common.ParseField;
 import org.elasticsearch.common.ParsingException;
 import org.elasticsearch.common.io.stream.StreamInput;
@@ -59,9 +60,10 @@ import java.util.TreeMap;
 public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQueryBuilder> {
     public static final String NAME = "query_string";
 
+    public static final Version V_5_1_0_UNRELEASED = Version.fromId(5010099);
+
     public static final boolean DEFAULT_AUTO_GENERATE_PHRASE_QUERIES = false;
     public static final int DEFAULT_MAX_DETERMINED_STATES = Operations.DEFAULT_MAX_DETERMINIZED_STATES;
-    public static final boolean DEFAULT_LOWERCASE_EXPANDED_TERMS = true;
     public static final boolean DEFAULT_ENABLE_POSITION_INCREMENTS = true;
     public static final boolean DEFAULT_ESCAPE = false;
     public static final boolean DEFAULT_USE_DIS_MAX = true;
@@ -71,7 +73,7 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
     public static final float DEFAULT_TIE_BREAKER = 0.0f;
     public static final Fuzziness DEFAULT_FUZZINESS = Fuzziness.AUTO;
     public static final Operator DEFAULT_OPERATOR = Operator.OR;
-    public static final Locale DEFAULT_LOCALE = Locale.ROOT;
+    public static final boolean DEFAULT_SPLIT_ON_WHITESPACE = true;
 
     private static final ParseField QUERY_FIELD = new ParseField("query");
     private static final ParseField FIELDS_FIELD = new ParseField("fields");
@@ -82,7 +84,8 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
     private static final ParseField ALLOW_LEADING_WILDCARD_FIELD = new ParseField("allow_leading_wildcard");
     private static final ParseField AUTO_GENERATE_PHRASE_QUERIES_FIELD = new ParseField("auto_generate_phrase_queries");
     private static final ParseField MAX_DETERMINED_STATES_FIELD = new ParseField("max_determined_states");
-    private static final ParseField LOWERCASE_EXPANDED_TERMS_FIELD = new ParseField("lowercase_expanded_terms");
+    private static final ParseField LOWERCASE_EXPANDED_TERMS_FIELD = new ParseField("lowercase_expanded_terms")
+            .withAllDeprecated("Decision is now made by the analyzer");
     private static final ParseField ENABLE_POSITION_INCREMENTS_FIELD = new ParseField("enable_position_increment");
     private static final ParseField ESCAPE_FIELD = new ParseField("escape");
     private static final ParseField USE_DIS_MAX_FIELD = new ParseField("use_dis_max");
@@ -96,9 +99,10 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
     private static final ParseField MINIMUM_SHOULD_MATCH_FIELD = new ParseField("minimum_should_match");
     private static final ParseField QUOTE_FIELD_SUFFIX_FIELD = new ParseField("quote_field_suffix");
     private static final ParseField LENIENT_FIELD = new ParseField("lenient");
-    private static final ParseField LOCALE_FIELD = new ParseField("locale");
+    private static final ParseField LOCALE_FIELD = new ParseField("locale")
+            .withAllDeprecated("Decision is now made by the analyzer");
     private static final ParseField TIME_ZONE_FIELD = new ParseField("time_zone");
-
+    private static final ParseField SPLIT_ON_WHITESPACE = new ParseField("split_on_whitespace");
 
     private final String queryString;
 
@@ -126,12 +130,8 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
 
     private Boolean analyzeWildcard;
 
-    private boolean lowercaseExpandedTerms = DEFAULT_LOWERCASE_EXPANDED_TERMS;
-
     private boolean enablePositionIncrements = DEFAULT_ENABLE_POSITION_INCREMENTS;
 
-    private Locale locale = DEFAULT_LOCALE;
-
     private Fuzziness fuzziness = DEFAULT_FUZZINESS;
 
     private int fuzzyPrefixLength = DEFAULT_FUZZY_PREFIX_LENGTH;
@@ -159,6 +159,8 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
     /** To limit effort spent determinizing regexp queries. */
     private int maxDeterminizedStates = DEFAULT_MAX_DETERMINED_STATES;
 
+    private boolean splitOnWhitespace = DEFAULT_SPLIT_ON_WHITESPACE;
+
     public QueryStringQueryBuilder(String queryString) {
         if (queryString == null) {
             throw new IllegalArgumentException("query text missing");
@@ -184,9 +186,13 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
         autoGeneratePhraseQueries = in.readBoolean();
         allowLeadingWildcard = in.readOptionalBoolean();
         analyzeWildcard = in.readOptionalBoolean();
-        lowercaseExpandedTerms = in.readBoolean();
+        if (in.getVersion().before(V_5_1_0_UNRELEASED)) {
+            in.readBoolean(); // lowercase_expanded_terms
+        }
         enablePositionIncrements = in.readBoolean();
-        locale = Locale.forLanguageTag(in.readString());
+        if (in.getVersion().before(V_5_1_0_UNRELEASED)) {
+            in.readString(); // locale
+        }
         fuzziness = new Fuzziness(in);
         fuzzyPrefixLength = in.readVInt();
         fuzzyMaxExpansions = in.readVInt();
@@ -200,6 +206,11 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
         timeZone = in.readOptionalTimeZone();
         escape = in.readBoolean();
         maxDeterminizedStates = in.readVInt();
+        if (in.getVersion().onOrAfter(V_5_1_0_UNRELEASED)) {
+            splitOnWhitespace = in.readBoolean();
+        } else {
+            splitOnWhitespace = DEFAULT_SPLIT_ON_WHITESPACE;
+        }
     }
 
     @Override
@@ -218,9 +229,13 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
         out.writeBoolean(this.autoGeneratePhraseQueries);
         out.writeOptionalBoolean(this.allowLeadingWildcard);
         out.writeOptionalBoolean(this.analyzeWildcard);
-        out.writeBoolean(this.lowercaseExpandedTerms);
+        if (out.getVersion().before(V_5_1_0_UNRELEASED)) {
+            out.writeBoolean(true); // lowercase_expanded_terms
+        }
         out.writeBoolean(this.enablePositionIncrements);
-        out.writeString(this.locale.toLanguageTag());
+        if (out.getVersion().before(V_5_1_0_UNRELEASED)) {
+            out.writeString(Locale.ROOT.toLanguageTag()); // locale
+        }
         this.fuzziness.writeTo(out);
         out.writeVInt(this.fuzzyPrefixLength);
         out.writeVInt(this.fuzzyMaxExpansions);
@@ -234,6 +249,9 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
         out.writeOptionalTimeZone(timeZone);
         out.writeBoolean(this.escape);
         out.writeVInt(this.maxDeterminizedStates);
+        if (out.getVersion().onOrAfter(V_5_1_0_UNRELEASED)) {
+            out.writeBoolean(this.splitOnWhitespace);
+        }
     }
 
     public String queryString() {
@@ -389,19 +407,6 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
         return this.allowLeadingWildcard;
     }
 
-    /**
-     * Whether terms of wildcard, prefix, fuzzy and range queries are to be automatically
-     * lower-cased or not.  Default is <tt>true</tt>.
-     */
-    public QueryStringQueryBuilder lowercaseExpandedTerms(boolean lowercaseExpandedTerms) {
-        this.lowercaseExpandedTerms = lowercaseExpandedTerms;
-        return this;
-    }
-
-    public boolean lowercaseExpandedTerms() {
-        return this.lowercaseExpandedTerms;
-    }
-
     /**
      * Set to <tt>true</tt> to enable position increments in result query. Defaults to
      * <tt>true</tt>.
@@ -473,6 +478,11 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
         return phraseSlop;
     }
 
+    public QueryStringQueryBuilder rewrite(String rewrite) {
+        this.rewrite = rewrite;
+        return this;
+    }
+
     /**
      * Set to <tt>true</tt> to enable analysis on wildcard and prefix queries.
      */
@@ -485,11 +495,6 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
         return this.analyzeWildcard;
     }
 
-    public QueryStringQueryBuilder rewrite(String rewrite) {
-        this.rewrite = rewrite;
-        return this;
-    }
-
     public String rewrite() {
         return this.rewrite;
     }
@@ -528,15 +533,6 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
         return this.lenient;
     }
 
-    public QueryStringQueryBuilder locale(Locale locale) {
-        this.locale = locale == null ? DEFAULT_LOCALE : locale;
-        return this;
-    }
-
-    public Locale locale() {
-        return this.locale;
-    }
-
     /**
      * In case of date field, we can adjust the from/to fields using a timezone
      */
@@ -570,6 +566,19 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
         return this.escape;
     }
 
+    /**
+     * Whether query text should be split on whitespace prior to analysis.
+     * Default is <code>{@value #DEFAULT_SPLIT_ON_WHITESPACE}</code>.
+     */
+    public QueryStringQueryBuilder splitOnWhitespace(boolean value) {
+        this.splitOnWhitespace = value;
+        return this;
+    }
+
+    public boolean splitOnWhitespace() {
+        return splitOnWhitespace;
+    }
+
     @Override
     protected void doXContent(XContentBuilder builder, Params params) throws IOException {
         builder.startObject(NAME);
@@ -597,7 +606,6 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
         if (this.allowLeadingWildcard != null) {
             builder.field(ALLOW_LEADING_WILDCARD_FIELD.getPreferredName(), this.allowLeadingWildcard);
         }
-        builder.field(LOWERCASE_EXPANDED_TERMS_FIELD.getPreferredName(), this.lowercaseExpandedTerms);
         builder.field(ENABLE_POSITION_INCREMENTS_FIELD.getPreferredName(), this.enablePositionIncrements);
         this.fuzziness.toXContent(builder, params);
         builder.field(FUZZY_PREFIX_LENGTH_FIELD.getPreferredName(), this.fuzzyPrefixLength);
@@ -621,11 +629,11 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
         if (this.lenient != null) {
             builder.field(LENIENT_FIELD.getPreferredName(), this.lenient);
         }
-        builder.field(LOCALE_FIELD.getPreferredName(), this.locale.toLanguageTag());
         if (this.timeZone != null) {
             builder.field(TIME_ZONE_FIELD.getPreferredName(), this.timeZone.getID());
         }
         builder.field(ESCAPE_FIELD.getPreferredName(), this.escape);
+        builder.field(SPLIT_ON_WHITESPACE.getPreferredName(), this.splitOnWhitespace);
         printBoostAndQueryName(builder);
         builder.endObject();
     }
@@ -642,7 +650,6 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
         float boost = AbstractQueryBuilder.DEFAULT_BOOST;
         boolean autoGeneratePhraseQueries = QueryStringQueryBuilder.DEFAULT_AUTO_GENERATE_PHRASE_QUERIES;
         int maxDeterminizedStates = QueryStringQueryBuilder.DEFAULT_MAX_DETERMINED_STATES;
-        boolean lowercaseExpandedTerms = QueryStringQueryBuilder.DEFAULT_LOWERCASE_EXPANDED_TERMS;
         boolean enablePositionIncrements = QueryStringQueryBuilder.DEFAULT_ENABLE_POSITION_INCREMENTS;
         boolean escape = QueryStringQueryBuilder.DEFAULT_ESCAPE;
         boolean useDisMax = QueryStringQueryBuilder.DEFAULT_USE_DIS_MAX;
@@ -657,10 +664,10 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
         Boolean lenient = null;
         Operator defaultOperator = QueryStringQueryBuilder.DEFAULT_OPERATOR;
         String timeZone = null;
-        Locale locale = QueryStringQueryBuilder.DEFAULT_LOCALE;
         Fuzziness fuzziness = QueryStringQueryBuilder.DEFAULT_FUZZINESS;
         String fuzzyRewrite = null;
         String rewrite = null;
+        boolean splitOnWhitespace = DEFAULT_SPLIT_ON_WHITESPACE;
         Map<String, Float> fieldsAndWeights = new HashMap<>();
         while ((token = parser.nextToken()) != XContentParser.Token.END_OBJECT) {
             if (token == XContentParser.Token.FIELD_NAME) {
@@ -707,7 +714,7 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
                 } else if (parseContext.getParseFieldMatcher().match(currentFieldName, MAX_DETERMINED_STATES_FIELD)) {
                     maxDeterminizedStates = parser.intValue();
                 } else if (parseContext.getParseFieldMatcher().match(currentFieldName, LOWERCASE_EXPANDED_TERMS_FIELD)) {
-                    lowercaseExpandedTerms = parser.booleanValue();
+                    // ignore, deprecated setting
                 } else if (parseContext.getParseFieldMatcher().match(currentFieldName, ENABLE_POSITION_INCREMENTS_FIELD)) {
                     enablePositionIncrements = parser.booleanValue();
                 } else if (parseContext.getParseFieldMatcher().match(currentFieldName, ESCAPE_FIELD)) {
@@ -739,8 +746,7 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
                 } else if (parseContext.getParseFieldMatcher().match(currentFieldName, LENIENT_FIELD)) {
                     lenient = parser.booleanValue();
                 } else if (parseContext.getParseFieldMatcher().match(currentFieldName, LOCALE_FIELD)) {
-                    String localeStr = parser.text();
-                    locale = Locale.forLanguageTag(localeStr);
+                    // ignore, deprecated setting
                 } else if (parseContext.getParseFieldMatcher().match(currentFieldName, TIME_ZONE_FIELD)) {
                     try {
                         timeZone = parser.text();
@@ -750,6 +756,8 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
                     }
                 } else if (parseContext.getParseFieldMatcher().match(currentFieldName, AbstractQueryBuilder.NAME_FIELD)) {
                     queryName = parser.text();
+                } else if (parseContext.getParseFieldMatcher().match(currentFieldName, SPLIT_ON_WHITESPACE)) {
+                    splitOnWhitespace = parser.booleanValue();
                 } else {
                     throw new ParsingException(parser.getTokenLocation(), "[" + QueryStringQueryBuilder.NAME +
                             "] query does not support [" + currentFieldName + "]");
@@ -772,7 +780,6 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
         queryStringQuery.allowLeadingWildcard(allowLeadingWildcard);
         queryStringQuery.autoGeneratePhraseQueries(autoGeneratePhraseQueries);
         queryStringQuery.maxDeterminizedStates(maxDeterminizedStates);
-        queryStringQuery.lowercaseExpandedTerms(lowercaseExpandedTerms);
         queryStringQuery.enablePositionIncrements(enablePositionIncrements);
         queryStringQuery.escape(escape);
         queryStringQuery.useDisMax(useDisMax);
@@ -788,9 +795,9 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
         queryStringQuery.quoteFieldSuffix(quoteFieldSuffix);
         queryStringQuery.lenient(lenient);
         queryStringQuery.timeZone(timeZone);
-        queryStringQuery.locale(locale);
         queryStringQuery.boost(boost);
         queryStringQuery.queryName(queryName);
+        queryStringQuery.splitOnWhitespace(splitOnWhitespace);
         return Optional.of(queryStringQuery);
     }
 
@@ -810,10 +817,8 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
                 Objects.equals(quoteFieldSuffix, other.quoteFieldSuffix) &&
                 Objects.equals(autoGeneratePhraseQueries, other.autoGeneratePhraseQueries) &&
                 Objects.equals(allowLeadingWildcard, other.allowLeadingWildcard) &&
-                Objects.equals(lowercaseExpandedTerms, other.lowercaseExpandedTerms) &&
                 Objects.equals(enablePositionIncrements, other.enablePositionIncrements) &&
                 Objects.equals(analyzeWildcard, other.analyzeWildcard) &&
-                Objects.equals(locale.toLanguageTag(), other.locale.toLanguageTag()) &&
                 Objects.equals(fuzziness, other.fuzziness) &&
                 Objects.equals(fuzzyPrefixLength, other.fuzzyPrefixLength) &&
                 Objects.equals(fuzzyMaxExpansions, other.fuzzyMaxExpansions) &&
@@ -827,16 +832,17 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
                 timeZone == null ? other.timeZone == null : other.timeZone != null &&
                 Objects.equals(timeZone.getID(), other.timeZone.getID()) &&
                 Objects.equals(escape, other.escape) &&
-                Objects.equals(maxDeterminizedStates, other.maxDeterminizedStates);
+                Objects.equals(maxDeterminizedStates, other.maxDeterminizedStates) &&
+                Objects.equals(splitOnWhitespace, other.splitOnWhitespace);
     }
 
     @Override
     protected int doHashCode() {
         return Objects.hash(queryString, defaultField, fieldsAndWeights, defaultOperator, analyzer, quoteAnalyzer,
-                quoteFieldSuffix, autoGeneratePhraseQueries, allowLeadingWildcard, lowercaseExpandedTerms,
-                enablePositionIncrements, analyzeWildcard, locale.toLanguageTag(), fuzziness, fuzzyPrefixLength,
+                quoteFieldSuffix, autoGeneratePhraseQueries, allowLeadingWildcard, analyzeWildcard,
+                enablePositionIncrements, fuzziness, fuzzyPrefixLength,
                 fuzzyMaxExpansions, fuzzyRewrite, phraseSlop, useDisMax, tieBreaker, rewrite, minimumShouldMatch, lenient,
-                timeZone == null ? 0 : timeZone.getID(), escape, maxDeterminizedStates);
+                timeZone == null ? 0 : timeZone.getID(), escape, maxDeterminizedStates, splitOnWhitespace);
     }
 
     @Override
@@ -890,9 +896,7 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
         qpSettings.autoGeneratePhraseQueries(autoGeneratePhraseQueries);
         qpSettings.allowLeadingWildcard(allowLeadingWildcard == null ? context.queryStringAllowLeadingWildcard() : allowLeadingWildcard);
         qpSettings.analyzeWildcard(analyzeWildcard == null ? context.queryStringAnalyzeWildcard() : analyzeWildcard);
-        qpSettings.lowercaseExpandedTerms(lowercaseExpandedTerms);
         qpSettings.enablePositionIncrements(enablePositionIncrements);
-        qpSettings.locale(locale);
         qpSettings.fuzziness(fuzziness);
         qpSettings.fuzzyPrefixLength(fuzzyPrefixLength);
         qpSettings.fuzzyMaxExpansions(fuzzyMaxExpansions);
@@ -904,6 +908,7 @@ public class QueryStringQueryBuilder extends AbstractQueryBuilder<QueryStringQue
         qpSettings.lenient(lenient == null ? context.queryStringLenient() : lenient);
         qpSettings.timeZone(timeZone);
         qpSettings.maxDeterminizedStates(maxDeterminizedStates);
+        qpSettings.splitOnWhitespace(splitOnWhitespace);
 
         MapperQueryParser queryParser = context.queryParser(qpSettings);
         Query query;

core/src/main/java/org/elasticsearch/index/query/SimpleQueryParser.java

@@ -30,10 +30,10 @@ import org.apache.lucene.search.FuzzyQuery;
 import org.apache.lucene.search.PrefixQuery;
 import org.apache.lucene.search.Query;
 import org.apache.lucene.search.SynonymQuery;
+import org.apache.lucene.util.BytesRef;
 import org.elasticsearch.index.mapper.MappedFieldType;
 
 import java.io.IOException;
-import java.util.Locale;
 import java.util.Map;
 import java.util.Objects;
 import java.util.List;
@@ -98,14 +98,13 @@ public class SimpleQueryParser extends org.apache.lucene.queryparser.simple.Simp
      */
     @Override
     public Query newFuzzyQuery(String text, int fuzziness) {
-        if (settings.lowercaseExpandedTerms()) {
-            text = text.toLowerCase(settings.locale());
-        }
         BooleanQuery.Builder bq = new BooleanQuery.Builder();
         bq.setDisableCoord(true);
         for (Map.Entry<String,Float> entry : weights.entrySet()) {
+            final String fieldName = entry.getKey();
             try {
-                Query query = new FuzzyQuery(new Term(entry.getKey(), text), fuzziness);
+                final BytesRef term = getAnalyzer().normalize(fieldName, text);
+                Query query = new FuzzyQuery(new Term(fieldName, term), fuzziness);
                 bq.add(wrapWithBoost(query, entry.getValue()), BooleanClause.Occur.SHOULD);
             } catch (RuntimeException e) {
                 rethrowUnlessLenient(e);
@@ -120,9 +119,18 @@ public class SimpleQueryParser extends org.apache.lucene.queryparser.simple.Simp
         bq.setDisableCoord(true);
         for (Map.Entry<String,Float> entry : weights.entrySet()) {
             try {
-                Query q = createPhraseQuery(entry.getKey(), text, slop);
+                String field = entry.getKey();
+                if (settings.quoteFieldSuffix() != null) {
+                    String quoteField = field + settings.quoteFieldSuffix();
+                    MappedFieldType quotedFieldType = context.fieldMapper(quoteField);
+                    if (quotedFieldType != null) {
+                        field = quoteField;
+                    }
+                }
+                Float boost = entry.getValue();
+                Query q = createPhraseQuery(field, text, slop);
                 if (q != null) {
-                    bq.add(wrapWithBoost(q, entry.getValue()), BooleanClause.Occur.SHOULD);
+                    bq.add(wrapWithBoost(q, boost), BooleanClause.Occur.SHOULD);
                 }
             } catch (RuntimeException e) {
                 rethrowUnlessLenient(e);
@@ -137,20 +145,19 @@ public class SimpleQueryParser extends org.apache.lucene.queryparser.simple.Simp
      */
     @Override
     public Query newPrefixQuery(String text) {
-        if (settings.lowercaseExpandedTerms()) {
-            text = text.toLowerCase(settings.locale());
-        }
         BooleanQuery.Builder bq = new BooleanQuery.Builder();
         bq.setDisableCoord(true);
         for (Map.Entry<String,Float> entry : weights.entrySet()) {
+            final String fieldName = entry.getKey();
             try {
                 if (settings.analyzeWildcard()) {
-                    Query analyzedQuery = newPossiblyAnalyzedQuery(entry.getKey(), text);
+                    Query analyzedQuery = newPossiblyAnalyzedQuery(fieldName, text);
                     if (analyzedQuery != null) {
                         bq.add(wrapWithBoost(analyzedQuery, entry.getValue()), BooleanClause.Occur.SHOULD);
                     }
                 } else {
-                    Query query = new PrefixQuery(new Term(entry.getKey(), text));
+                    Term term = new Term(fieldName, getAnalyzer().normalize(fieldName, text));
+                    Query query = new PrefixQuery(term);
                     bq.add(wrapWithBoost(query, entry.getValue()), BooleanClause.Occur.SHOULD);
                 }
             } catch (RuntimeException e) {
@@ -173,11 +180,11 @@ public class SimpleQueryParser extends org.apache.lucene.queryparser.simple.Simp
      * of {@code TermQuery}s and {@code PrefixQuery}s
      */
     private Query newPossiblyAnalyzedQuery(String field, String termStr) {
-        List<List<String>> tlist = new ArrayList<> ();
+        List<List<BytesRef>> tlist = new ArrayList<> ();
         // get Analyzer from superclass and tokenize the term
         try (TokenStream source = getAnalyzer().tokenStream(field, termStr)) {
             source.reset();
-            List<String> currentPos = new ArrayList<>();
+            List<BytesRef> currentPos = new ArrayList<>();
             CharTermAttribute termAtt = source.addAttribute(CharTermAttribute.class);
             PositionIncrementAttribute posAtt = source.addAttribute(PositionIncrementAttribute.class);
 
@@ -188,7 +195,8 @@ public class SimpleQueryParser extends org.apache.lucene.queryparser.simple.Simp
                         tlist.add(currentPos);
                         currentPos = new ArrayList<>();
                     }
-                    currentPos.add(termAtt.toString());
+                    final BytesRef term = getAnalyzer().normalize(field, termAtt.toString());
+                    currentPos.add(term);
                     hasMoreTokens = source.incrementToken();
                 }
                 if (currentPos.isEmpty() == false) {
@@ -214,7 +222,7 @@ public class SimpleQueryParser extends org.apache.lucene.queryparser.simple.Simp
         // build a boolean query with prefix on the last position only.
         BooleanQuery.Builder builder = new BooleanQuery.Builder();
         for (int pos = 0; pos < tlist.size(); pos++) {
-            List<String> plist = tlist.get(pos);
+            List<BytesRef> plist = tlist.get(pos);
             boolean isLastPos = (pos == tlist.size()-1);
             Query posQuery;
             if (plist.size() == 1) {
@@ -232,7 +240,7 @@ public class SimpleQueryParser extends org.apache.lucene.queryparser.simple.Simp
                 posQuery = new SynonymQuery(terms);
             } else {
                 BooleanQuery.Builder innerBuilder = new BooleanQuery.Builder();
-                for (String token : plist) {
+                for (BytesRef token : plist) {
                     innerBuilder.add(new BooleanClause(new PrefixQuery(new Term(field, token)),
                         BooleanClause.Occur.SHOULD));
                 }
@@ -248,14 +256,12 @@ public class SimpleQueryParser extends org.apache.lucene.queryparser.simple.Simp
      * their default values
      */
     static class Settings {
-        /** Locale to use for parsing. */
-        private Locale locale = SimpleQueryStringBuilder.DEFAULT_LOCALE;
-        /** Specifies whether parsed terms should be lowercased. */
-        private boolean lowercaseExpandedTerms = SimpleQueryStringBuilder.DEFAULT_LOWERCASE_EXPANDED_TERMS;
         /** Specifies whether lenient query parsing should be used. */
         private boolean lenient = SimpleQueryStringBuilder.DEFAULT_LENIENT;
         /** Specifies whether wildcards should be analyzed. */
         private boolean analyzeWildcard = SimpleQueryStringBuilder.DEFAULT_ANALYZE_WILDCARD;
+        /** Specifies a suffix, if any, to apply to field names for phrase matching. */
+        private String quoteFieldSuffix = null;
 
         /**
          * Generates default {@link Settings} object (uses ROOT locale, does
@@ -264,36 +270,6 @@ public class SimpleQueryParser extends org.apache.lucene.queryparser.simple.Simp
         public Settings() {
         }
 
-        public Settings(Locale locale, Boolean lowercaseExpandedTerms, Boolean lenient, Boolean analyzeWildcard) {
-            this.locale = locale;
-            this.lowercaseExpandedTerms = lowercaseExpandedTerms;
-            this.lenient = lenient;
-            this.analyzeWildcard = analyzeWildcard;
-        }
-
-        /** Specifies the locale to use for parsing, Locale.ROOT by default. */
-        public void locale(Locale locale) {
-            this.locale = (locale != null) ? locale : SimpleQueryStringBuilder.DEFAULT_LOCALE;
-        }
-
-        /** Returns the locale to use for parsing. */
-        public Locale locale() {
-            return this.locale;
-        }
-
-        /**
-         * Specifies whether to lowercase parse terms, defaults to true if
-         * unset.
-         */
-        public void lowercaseExpandedTerms(boolean lowercaseExpandedTerms) {
-            this.lowercaseExpandedTerms = lowercaseExpandedTerms;
-        }
-
-        /** Returns whether to lowercase parse terms. */
-        public boolean lowercaseExpandedTerms() {
-            return this.lowercaseExpandedTerms;
-        }
-
         /** Specifies whether to use lenient parsing, defaults to false. */
         public void lenient(boolean lenient) {
             this.lenient = lenient;
@@ -314,12 +290,24 @@ public class SimpleQueryParser extends org.apache.lucene.queryparser.simple.Simp
             return analyzeWildcard;
         }
 
+        /**
+         * Set the suffix to append to field names for phrase matching.
+         */
+        public void quoteFieldSuffix(String suffix) {
+            this.quoteFieldSuffix = suffix;
+        }
+
+        /**
+         * Return the suffix to append for phrase matching, or {@code null} if
+         * no suffix should be appended.
+         */
+        public String quoteFieldSuffix() {
+            return quoteFieldSuffix;
+        }
+
         @Override
         public int hashCode() {
-            // checking the return value of toLanguageTag() for locales only.
-            // For further reasoning see
-            // https://issues.apache.org/jira/browse/LUCENE-4021
-            return Objects.hash(locale.toLanguageTag(), lowercaseExpandedTerms, lenient, analyzeWildcard);
+            return Objects.hash(lenient, analyzeWildcard, quoteFieldSuffix);
         }
 
         @Override
@@ -331,14 +319,8 @@ public class SimpleQueryParser extends org.apache.lucene.queryparser.simple.Simp
                 return false;
             }
             Settings other = (Settings) obj;
-
-            // checking the return value of toLanguageTag() for locales only.
-            // For further reasoning see
-            // https://issues.apache.org/jira/browse/LUCENE-4021
-            return (Objects.equals(locale.toLanguageTag(), other.locale.toLanguageTag())
-                    && Objects.equals(lowercaseExpandedTerms, other.lowercaseExpandedTerms)
-                    && Objects.equals(lenient, other.lenient)
-                    && Objects.equals(analyzeWildcard, other.analyzeWildcard));
+            return Objects.equals(lenient, other.lenient) && Objects.equals(analyzeWildcard, other.analyzeWildcard)
+                    && Objects.equals(quoteFieldSuffix, other.quoteFieldSuffix);
         }
     }
 }

core/src/main/java/org/elasticsearch/index/query/SimpleQueryStringBuilder.java

@@ -22,6 +22,7 @@ package org.elasticsearch.index.query;
 import org.apache.lucene.analysis.Analyzer;
 import org.apache.lucene.search.BooleanQuery;
 import org.apache.lucene.search.Query;
+import org.elasticsearch.Version;
 import org.elasticsearch.common.ParseField;
 import org.elasticsearch.common.ParsingException;
 import org.elasticsearch.common.Strings;
@@ -78,10 +79,6 @@ import java.util.TreeMap;
  * > online documentation</a>.
  */
 public class SimpleQueryStringBuilder extends AbstractQueryBuilder<SimpleQueryStringBuilder> {
-    /** Default locale used for parsing.*/
-    public static final Locale DEFAULT_LOCALE = Locale.ROOT;
-    /** Default for lowercasing parsed terms.*/
-    public static final boolean DEFAULT_LOWERCASE_EXPANDED_TERMS = true;
     /** Default for using lenient query parsing.*/
     public static final boolean DEFAULT_LENIENT = false;
     /** Default for wildcard analysis.*/
@@ -94,16 +91,21 @@ public class SimpleQueryStringBuilder extends AbstractQueryBuilder<SimpleQuerySt
     /** Name for (de-)serialization. */
     public static final String NAME = "simple_query_string";
 
+    public static final Version V_5_1_0_UNRELEASED = Version.fromId(5010099);
+
     private static final ParseField MINIMUM_SHOULD_MATCH_FIELD = new ParseField("minimum_should_match");
     private static final ParseField ANALYZE_WILDCARD_FIELD = new ParseField("analyze_wildcard");
     private static final ParseField LENIENT_FIELD = new ParseField("lenient");
-    private static final ParseField LOWERCASE_EXPANDED_TERMS_FIELD = new ParseField("lowercase_expanded_terms");
-    private static final ParseField LOCALE_FIELD = new ParseField("locale");
+    private static final ParseField LOWERCASE_EXPANDED_TERMS_FIELD = new ParseField("lowercase_expanded_terms")
+            .withAllDeprecated("Decision is now made by the analyzer");
+    private static final ParseField LOCALE_FIELD = new ParseField("locale")
+            .withAllDeprecated("Decision is now made by the analyzer");
     private static final ParseField FLAGS_FIELD = new ParseField("flags");
     private static final ParseField DEFAULT_OPERATOR_FIELD = new ParseField("default_operator");
     private static final ParseField ANALYZER_FIELD = new ParseField("analyzer");
     private static final ParseField QUERY_FIELD = new ParseField("query");
     private static final ParseField FIELDS_FIELD = new ParseField("fields");
+    private static final ParseField QUOTE_FIELD_SUFFIX_FIELD = new ParseField("quote_field_suffix");
 
     /** Query text to parse. */
     private final String queryText;
@@ -153,11 +155,18 @@ public class SimpleQueryStringBuilder extends AbstractQueryBuilder<SimpleQuerySt
         flags = in.readInt();
         analyzer = in.readOptionalString();
         defaultOperator = Operator.readFromStream(in);
-        settings.lowercaseExpandedTerms(in.readBoolean());
+        if (in.getVersion().before(V_5_1_0_UNRELEASED)) {
+            in.readBoolean(); // lowercase_expanded_terms
+        }
         settings.lenient(in.readBoolean());
         settings.analyzeWildcard(in.readBoolean());
-        settings.locale(Locale.forLanguageTag(in.readString()));
+        if (in.getVersion().before(V_5_1_0_UNRELEASED)) {
+            in.readString(); // locale
+        }
         minimumShouldMatch = in.readOptionalString();
+        if (in.getVersion().onOrAfter(V_5_1_0_UNRELEASED)) {
+            settings.quoteFieldSuffix(in.readOptionalString());
+        }
     }
 
     @Override
@@ -171,11 +180,18 @@ public class SimpleQueryStringBuilder extends AbstractQueryBuilder<SimpleQuerySt
         out.writeInt(flags);
         out.writeOptionalString(analyzer);
         defaultOperator.writeTo(out);
-        out.writeBoolean(settings.lowercaseExpandedTerms());
+        if (out.getVersion().before(V_5_1_0_UNRELEASED)) {
+            out.writeBoolean(true); // lowercase_expanded_terms
+        }
         out.writeBoolean(settings.lenient());
         out.writeBoolean(settings.analyzeWildcard());
-        out.writeString(settings.locale().toLanguageTag());
+        if (out.getVersion().before(V_5_1_0_UNRELEASED)) {
+            out.writeString(Locale.ROOT.toLanguageTag()); // locale
+        }
         out.writeOptionalString(minimumShouldMatch);
+        if (out.getVersion().onOrAfter(V_5_1_0_UNRELEASED)) {
+            out.writeOptionalString(settings.quoteFieldSuffix());
+        }
     }
 
     /** Returns the text to parse the query from. */
@@ -268,28 +284,18 @@ public class SimpleQueryStringBuilder extends AbstractQueryBuilder<SimpleQuerySt
     }
 
     /**
-     * Specifies whether parsed terms for this query should be lower-cased.
-     * Defaults to true if not set.
+     * Set the suffix to append to field names for phrase matching.
      */
-    public SimpleQueryStringBuilder lowercaseExpandedTerms(boolean lowercaseExpandedTerms) {
-        this.settings.lowercaseExpandedTerms(lowercaseExpandedTerms);
+    public SimpleQueryStringBuilder quoteFieldSuffix(String suffix) {
+        settings.quoteFieldSuffix(suffix);
         return this;
     }
 
-    /** Returns whether parsed terms should be lower cased for this query. */
-    public boolean lowercaseExpandedTerms() {
-        return this.settings.lowercaseExpandedTerms();
-    }
-
-    /** Specifies the locale for parsing terms. Defaults to ROOT if none is set. */
-    public SimpleQueryStringBuilder locale(Locale locale) {
-        this.settings.locale(locale);
-        return this;
-    }
-
-    /** Returns the locale for parsing terms for this query. */
-    public Locale locale() {
-        return this.settings.locale();
+    /**
+     * Return the suffix to append to field names for phrase matching.
+     */
+    public String quoteFieldSuffix() {
+        return settings.quoteFieldSuffix();
     }
 
     /** Specifies whether query parsing should be lenient. Defaults to false. */
@@ -404,10 +410,11 @@ public class SimpleQueryStringBuilder extends AbstractQueryBuilder<SimpleQuerySt
 
         builder.field(FLAGS_FIELD.getPreferredName(), flags);
         builder.field(DEFAULT_OPERATOR_FIELD.getPreferredName(), defaultOperator.name().toLowerCase(Locale.ROOT));
-        builder.field(LOWERCASE_EXPANDED_TERMS_FIELD.getPreferredName(), settings.lowercaseExpandedTerms());
         builder.field(LENIENT_FIELD.getPreferredName(), settings.lenient());
         builder.field(ANALYZE_WILDCARD_FIELD.getPreferredName(), settings.analyzeWildcard());
-        builder.field(LOCALE_FIELD.getPreferredName(), (settings.locale().toLanguageTag()));
+        if (settings.quoteFieldSuffix() != null) {
+            builder.field(QUOTE_FIELD_SUFFIX_FIELD.getPreferredName(), settings.quoteFieldSuffix());
+        }
 
         if (minimumShouldMatch != null) {
             builder.field(MINIMUM_SHOULD_MATCH_FIELD.getPreferredName(), minimumShouldMatch);
@@ -430,9 +437,8 @@ public class SimpleQueryStringBuilder extends AbstractQueryBuilder<SimpleQuerySt
         String analyzerName = null;
         int flags = SimpleQueryStringFlag.ALL.value();
         boolean lenient = SimpleQueryStringBuilder.DEFAULT_LENIENT;
-        boolean lowercaseExpandedTerms = SimpleQueryStringBuilder.DEFAULT_LOWERCASE_EXPANDED_TERMS;
         boolean analyzeWildcard = SimpleQueryStringBuilder.DEFAULT_ANALYZE_WILDCARD;
-        Locale locale = null;
+        String quoteFieldSuffix = null;
 
         XContentParser.Token token;
         while ((token = parser.nextToken()) != XContentParser.Token.END_OBJECT) {
@@ -483,10 +489,9 @@ public class SimpleQueryStringBuilder extends AbstractQueryBuilder<SimpleQuerySt
                         }
                     }
                 } else if (parseContext.getParseFieldMatcher().match(currentFieldName, LOCALE_FIELD)) {
-                    String localeStr = parser.text();
-                    locale = Locale.forLanguageTag(localeStr);
+                    // ignore, deprecated setting
                 } else if (parseContext.getParseFieldMatcher().match(currentFieldName, LOWERCASE_EXPANDED_TERMS_FIELD)) {
-                    lowercaseExpandedTerms = parser.booleanValue();
+                    // ignore, deprecated setting
                 } else if (parseContext.getParseFieldMatcher().match(currentFieldName, LENIENT_FIELD)) {
                     lenient = parser.booleanValue();
                 } else if (parseContext.getParseFieldMatcher().match(currentFieldName, ANALYZE_WILDCARD_FIELD)) {
@@ -495,6 +500,8 @@ public class SimpleQueryStringBuilder extends AbstractQueryBuilder<SimpleQuerySt
                     queryName = parser.text();
                 } else if (parseContext.getParseFieldMatcher().match(currentFieldName, MINIMUM_SHOULD_MATCH_FIELD)) {
                     minimumShouldMatch = parser.textOrNull();
+                } else if (parseContext.getParseFieldMatcher().match(currentFieldName, QUOTE_FIELD_SUFFIX_FIELD)) {
+                    quoteFieldSuffix = parser.textOrNull();
                 } else {
                     throw new ParsingException(parser.getTokenLocation(), "[" + SimpleQueryStringBuilder.NAME +
                             "] unsupported field [" + parser.currentName() + "]");
@@ -512,8 +519,8 @@ public class SimpleQueryStringBuilder extends AbstractQueryBuilder<SimpleQuerySt
 
         SimpleQueryStringBuilder qb = new SimpleQueryStringBuilder(queryBody);
         qb.boost(boost).fields(fieldsAndWeights).analyzer(analyzerName).queryName(queryName).minimumShouldMatch(minimumShouldMatch);
-        qb.flags(flags).defaultOperator(defaultOperator).locale(locale).lowercaseExpandedTerms(lowercaseExpandedTerms);
-        qb.lenient(lenient).analyzeWildcard(analyzeWildcard).boost(boost);
+        qb.flags(flags).defaultOperator(defaultOperator);
+        qb.lenient(lenient).analyzeWildcard(analyzeWildcard).boost(boost).quoteFieldSuffix(quoteFieldSuffix);
         return Optional.of(qb);
     }
 

core/src/main/java/org/elasticsearch/index/shard/IndexShard.java

@@ -536,26 +536,27 @@ public class IndexShard extends AbstractIndexShardComponent implements IndicesCl
         return new Engine.Index(uid, doc, version, versionType, origin, startTime, autoGeneratedIdTimestamp, isRetry);
     }
 
-    public void index(Engine.Index index) {
+    public Engine.IndexResult index(Engine.Index index) {
         ensureWriteAllowed(index);
         Engine engine = getEngine();
-        index(engine, index);
+        return index(engine, index);
     }
 
-    private void index(Engine engine, Engine.Index index) {
+    private Engine.IndexResult index(Engine engine, Engine.Index index) {
         active.set(true);
+        final Engine.IndexResult result;
         index = indexingOperationListeners.preIndex(index);
         try {
             if (logger.isTraceEnabled()) {
                 logger.trace("index [{}][{}]{}", index.type(), index.id(), index.docs());
             }
-            engine.index(index);
-            index.endTime(System.nanoTime());
+            result = engine.index(index);
         } catch (Exception e) {
             indexingOperationListeners.postIndex(index, e);
             throw e;
         }
-        indexingOperationListeners.postIndex(index, index.isCreated());
+        indexingOperationListeners.postIndex(index, result);
+        return result;
     }
 
     public Engine.Delete prepareDeleteOnPrimary(String type, String id, long version, VersionType versionType) {
@@ -577,30 +578,30 @@ public class IndexShard extends AbstractIndexShardComponent implements IndicesCl
 
     static Engine.Delete prepareDelete(String type, String id, Term uid, long version, VersionType versionType, Engine.Operation.Origin origin) {
         long startTime = System.nanoTime();
-        return new Engine.Delete(type, id, uid, version, versionType, origin, startTime, false);
+        return new Engine.Delete(type, id, uid, version, versionType, origin, startTime);
     }
 
-    public void delete(Engine.Delete delete) {
+    public Engine.DeleteResult delete(Engine.Delete delete) {
         ensureWriteAllowed(delete);
         Engine engine = getEngine();
-        delete(engine, delete);
+        return delete(engine, delete);
     }
 
-    private void delete(Engine engine, Engine.Delete delete) {
+    private Engine.DeleteResult delete(Engine engine, Engine.Delete delete) {
         active.set(true);
+        final Engine.DeleteResult result;
         delete = indexingOperationListeners.preDelete(delete);
         try {
             if (logger.isTraceEnabled()) {
                 logger.trace("delete [{}]", delete.uid().text());
             }
-            engine.delete(delete);
-            delete.endTime(System.nanoTime());
+            result = engine.delete(delete);
         } catch (Exception e) {
             indexingOperationListeners.postDelete(delete, e);
             throw e;
         }
-
-        indexingOperationListeners.postDelete(delete);
+        indexingOperationListeners.postDelete(delete, result);
+        return result;
     }
 
     public Engine.GetResult get(Engine.Get get) {

core/src/main/java/org/elasticsearch/index/shard/IndexingOperationListener.java

@@ -38,12 +38,17 @@ public interface IndexingOperationListener {
     }
 
     /**
-     * Called after the indexing operation occurred.
+     * Called after the indexing operation occurred. Note that this is
+     * also called when indexing a document did not succeed due to document
+     * related failures. See {@link #postIndex(Engine.Index, Exception)}
+     * for engine level failures
      */
-    default void postIndex(Engine.Index index, boolean created) {}
+    default void postIndex(Engine.Index index, Engine.IndexResult result) {}
 
     /**
-     * Called after the indexing operation occurred with exception.
+     * Called after the indexing operation occurred with engine level exception.
+     * See {@link #postIndex(Engine.Index, Engine.IndexResult)} for document
+     * related failures
      */
     default void postIndex(Engine.Index index, Exception ex) {}
 
@@ -56,12 +61,17 @@ public interface IndexingOperationListener {
 
 
     /**
-     * Called after the delete operation occurred.
+     * Called after the delete operation occurred. Note that this is
+     * also called when deleting a document did not succeed due to document
+     * related failures. See {@link #postDelete(Engine.Delete, Exception)}
+     * for engine level failures
      */
-    default void postDelete(Engine.Delete delete) {}
+    default void postDelete(Engine.Delete delete, Engine.DeleteResult result) {}
 
     /**
-     * Called after the delete operation occurred with exception.
+     * Called after the delete operation occurred with engine level exception.
+     * See {@link #postDelete(Engine.Delete, Engine.DeleteResult)} for document
+     * related failures
      */
     default void postDelete(Engine.Delete delete, Exception ex) {}
 
@@ -91,11 +101,11 @@ public interface IndexingOperationListener {
         }
 
         @Override
-        public void postIndex(Engine.Index index, boolean created) {
+        public void postIndex(Engine.Index index, Engine.IndexResult result) {
             assert index != null;
             for (IndexingOperationListener listener : listeners) {
                 try {
-                    listener.postIndex(index, created);
+                    listener.postIndex(index, result);
                 } catch (Exception e) {
                     logger.warn((Supplier<?>) () -> new ParameterizedMessage("postIndex listener [{}] failed", listener), e);
                 }
@@ -129,11 +139,11 @@ public interface IndexingOperationListener {
         }
 
         @Override
-        public void postDelete(Engine.Delete delete) {
+        public void postDelete(Engine.Delete delete, Engine.DeleteResult result) {
             assert delete != null;
             for (IndexingOperationListener listener : listeners) {
                 try {
-                    listener.postDelete(delete);
+                    listener.postDelete(delete, result);
                 } catch (Exception e) {
                     logger.warn((Supplier<?>) () -> new ParameterizedMessage("postDelete listener [{}] failed", listener), e);
                 }

core/src/main/java/org/elasticsearch/index/shard/InternalIndexingStats.java

@@ -74,14 +74,18 @@ final class InternalIndexingStats implements IndexingOperationListener {
     }
 
     @Override
-    public void postIndex(Engine.Index index, boolean created) {
-        if (!index.origin().isRecovery()) {
-            long took = index.endTime() - index.startTime();
-            totalStats.indexMetric.inc(took);
-            totalStats.indexCurrent.dec();
-            StatsHolder typeStats = typeStats(index.type());
-            typeStats.indexMetric.inc(took);
-            typeStats.indexCurrent.dec();
+    public void postIndex(Engine.Index index, Engine.IndexResult result) {
+        if (result.hasFailure() == false) {
+            if (!index.origin().isRecovery()) {
+                long took = result.getTook();
+                totalStats.indexMetric.inc(took);
+                totalStats.indexCurrent.dec();
+                StatsHolder typeStats = typeStats(index.type());
+                typeStats.indexMetric.inc(took);
+                typeStats.indexCurrent.dec();
+            }
+        } else {
+            postIndex(index, result.getFailure());
         }
     }
 
@@ -106,14 +110,18 @@ final class InternalIndexingStats implements IndexingOperationListener {
     }
 
     @Override
-    public void postDelete(Engine.Delete delete) {
-        if (!delete.origin().isRecovery()) {
-            long took = delete.endTime() - delete.startTime();
-            totalStats.deleteMetric.inc(took);
-            totalStats.deleteCurrent.dec();
-            StatsHolder typeStats = typeStats(delete.type());
-            typeStats.deleteMetric.inc(took);
-            typeStats.deleteCurrent.dec();
+    public void postDelete(Engine.Delete delete, Engine.DeleteResult result) {
+        if (result.hasFailure() == false) {
+            if (!delete.origin().isRecovery()) {
+                long took = result.getTook();
+                totalStats.deleteMetric.inc(took);
+                totalStats.deleteCurrent.dec();
+                StatsHolder typeStats = typeStats(delete.type());
+                typeStats.deleteMetric.inc(took);
+                typeStats.deleteCurrent.dec();
+            }
+        } else {
+            postDelete(delete, result.getFailure());
         }
     }
 

core/src/main/java/org/elasticsearch/index/shard/TranslogRecoveryPerformer.java

@@ -170,7 +170,7 @@ public class TranslogRecoveryPerformer {
                         logger.trace("[translog] recover [delete] op of [{}][{}]", uid.type(), uid.id());
                     }
                     final Engine.Delete engineDelete = new Engine.Delete(uid.type(), uid.id(), delete.uid(), delete.version(),
-                        delete.versionType().versionTypeForReplicationAndRecovery(), origin, System.nanoTime(), false);
+                        delete.versionType().versionTypeForReplicationAndRecovery(), origin, System.nanoTime());
                     delete(engine, engineDelete);
                     break;
                 default:

core/src/main/java/org/elasticsearch/index/translog/Translog.java

@@ -830,13 +830,13 @@ public class Translog extends AbstractIndexShardComponent implements IndexShardC
             }
         }
 
-        public Index(Engine.Index index) {
+        public Index(Engine.Index index, Engine.IndexResult indexResult) {
             this.id = index.id();
             this.type = index.type();
             this.source = index.source();
             this.routing = index.routing();
             this.parent = index.parent();
-            this.version = index.version();
+            this.version = indexResult.getVersion();
             this.timestamp = index.timestamp();
             this.ttl = index.ttl();
             this.versionType = index.versionType();
@@ -994,9 +994,9 @@ public class Translog extends AbstractIndexShardComponent implements IndexShardC
             assert versionType.validateVersionForWrites(this.version);
         }
 
-        public Delete(Engine.Delete delete) {
+        public Delete(Engine.Delete delete, Engine.DeleteResult deleteResult) {
             this.uid = delete.uid();
-            this.version = delete.version();
+            this.version = deleteResult.getVersion();
             this.versionType = delete.versionType();
         }
 

core/src/main/java/org/elasticsearch/indices/AbstractIndexShardCacheEntity.java

@@ -19,40 +19,15 @@
 
 package org.elasticsearch.indices;
 
-import org.apache.lucene.index.DirectoryReader;
 import org.elasticsearch.common.bytes.BytesReference;
 import org.elasticsearch.common.cache.RemovalNotification;
-import org.elasticsearch.common.io.stream.BytesStreamOutput;
-import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.index.cache.request.ShardRequestCache;
 import org.elasticsearch.index.shard.IndexShard;
 
-import java.io.IOException;
-
 /**
  * Abstract base class for the an {@link IndexShard} level {@linkplain IndicesRequestCache.CacheEntity}.
  */
 abstract class AbstractIndexShardCacheEntity implements IndicesRequestCache.CacheEntity {
-    @FunctionalInterface
-    public interface Loader {
-        void load(StreamOutput out) throws IOException;
-    }
-
-    private final Loader loader;
-    private boolean loadedFromCache = true;
-
-    protected AbstractIndexShardCacheEntity(Loader loader) {
-        this.loader = loader;
-    }
-
-    /**
-     * When called after passing this through
-     * {@link IndicesRequestCache#getOrCompute(IndicesRequestCache.CacheEntity, DirectoryReader, BytesReference)} this will return whether
-     * or not the result was loaded from the cache.
-     */
-    public final boolean loadedFromCache() {
-        return loadedFromCache;
-    }
 
     /**
      * Get the {@linkplain ShardRequestCache} used to track cache statistics.
@@ -60,27 +35,7 @@ abstract class AbstractIndexShardCacheEntity implements IndicesRequestCache.Cach
     protected abstract ShardRequestCache stats();
 
     @Override
-    public final IndicesRequestCache.Value loadValue() throws IOException {
-        /* BytesStreamOutput allows to pass the expected size but by default uses
-         * BigArrays.PAGE_SIZE_IN_BYTES which is 16k. A common cached result ie.
-         * a date histogram with 3 buckets is ~100byte so 16k might be very wasteful
-         * since we don't shrink to the actual size once we are done serializing.
-         * By passing 512 as the expected size we will resize the byte array in the stream
-         * slowly until we hit the page size and don't waste too much memory for small query
-         * results.*/
-        final int expectedSizeInBytes = 512;
-        try (BytesStreamOutput out = new BytesStreamOutput(expectedSizeInBytes)) {
-            loader.load(out);
-            // for now, keep the paged data structure, which might have unused bytes to fill a page, but better to keep
-            // the memory properly paged instead of having varied sized bytes
-            final BytesReference reference = out.bytes();
-            loadedFromCache = false;
-            return new IndicesRequestCache.Value(reference, out.ramBytesUsed());
-        }
-    }
-
-    @Override
-    public final void onCached(IndicesRequestCache.Key key, IndicesRequestCache.Value value) {
+    public final void onCached(IndicesRequestCache.Key key, BytesReference value) {
         stats().onCached(key, value);
     }
 
@@ -95,7 +50,7 @@ abstract class AbstractIndexShardCacheEntity implements IndicesRequestCache.Cach
     }
 
     @Override
-    public final void onRemoval(RemovalNotification<IndicesRequestCache.Key, IndicesRequestCache.Value> notification) {
+    public final void onRemoval(RemovalNotification<IndicesRequestCache.Key, BytesReference> notification) {
         stats().onRemoval(notification.getKey(), notification.getValue(),
                 notification.getRemovalReason() == RemovalNotification.RemovalReason.EVICTED);
     }

core/src/main/java/org/elasticsearch/indices/IndexingMemoryController.java

@@ -189,11 +189,6 @@ public class IndexingMemoryController extends AbstractComponent implements Index
         statusChecker.run();
     }
 
-    /** called by IndexShard to record that this many bytes were written to translog */
-    public void bytesWritten(int bytes) {
-        statusChecker.bytesWritten(bytes);
-    }
-
     /** Asks this shard to throttle indexing to one thread */
     protected void activateThrottling(IndexShard shard) {
         shard.activateThrottling();
@@ -205,17 +200,20 @@ public class IndexingMemoryController extends AbstractComponent implements Index
     }
 
     @Override
-    public void postIndex(Engine.Index index, boolean created) {
-        recordOperationBytes(index);
+    public void postIndex(Engine.Index index, Engine.IndexResult result) {
+        recordOperationBytes(index, result);
     }
 
     @Override
-    public void postDelete(Engine.Delete delete) {
-        recordOperationBytes(delete);
+    public void postDelete(Engine.Delete delete, Engine.DeleteResult result) {
+        recordOperationBytes(delete, result);
     }
 
-    private void recordOperationBytes(Engine.Operation op) {
-        bytesWritten(op.sizeInBytes());
+    /** called by IndexShard to record estimated bytes written to translog for the operation */
+    private void recordOperationBytes(Engine.Operation operation, Engine.Result result) {
+        if (result.hasFailure() == false) {
+            statusChecker.bytesWritten(operation.estimatedSizeInBytes());
+        }
     }
 
     private static final class ShardAndBytesUsed implements Comparable<ShardAndBytesUsed> {

core/src/main/java/org/elasticsearch/indices/IndicesRequestCache.java

@@ -41,12 +41,12 @@ import org.elasticsearch.common.unit.TimeValue;
 import org.elasticsearch.common.util.concurrent.ConcurrentCollections;
 
 import java.io.Closeable;
-import java.io.IOException;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.Iterator;
 import java.util.Set;
 import java.util.concurrent.ConcurrentMap;
+import java.util.function.Supplier;
 
 /**
  * The indices request cache allows to cache a shard level request stage responses, helping with improving
@@ -62,7 +62,7 @@ import java.util.concurrent.ConcurrentMap;
  * is functional.
  */
 public final class IndicesRequestCache extends AbstractComponent implements RemovalListener<IndicesRequestCache.Key,
-    IndicesRequestCache.Value>, Closeable {
+    BytesReference>, Closeable {
 
     /**
      * A setting to enable or disable request caching on an index level. Its dynamic by default
@@ -79,14 +79,14 @@ public final class IndicesRequestCache extends AbstractComponent implements Remo
     private final Set<CleanupKey> keysToClean = ConcurrentCollections.newConcurrentSet();
     private final ByteSizeValue size;
     private final TimeValue expire;
-    private final Cache<Key, Value> cache;
+    private final Cache<Key, BytesReference> cache;
 
     IndicesRequestCache(Settings settings) {
         super(settings);
         this.size = INDICES_CACHE_QUERY_SIZE.get(settings);
         this.expire = INDICES_CACHE_QUERY_EXPIRE.exists(settings) ? INDICES_CACHE_QUERY_EXPIRE.get(settings) : null;
         long sizeInBytes = size.getBytes();
-        CacheBuilder<Key, Value> cacheBuilder = CacheBuilder.<Key, Value>builder()
+        CacheBuilder<Key, BytesReference> cacheBuilder = CacheBuilder.<Key, BytesReference>builder()
             .setMaximumWeight(sizeInBytes).weigher((k, v) -> k.ramBytesUsed() + v.ramBytesUsed()).removalListener(this);
         if (expire != null) {
             cacheBuilder.setExpireAfterAccess(expire);
@@ -105,15 +105,16 @@ public final class IndicesRequestCache extends AbstractComponent implements Remo
     }
 
     @Override
-    public void onRemoval(RemovalNotification<Key, Value> notification) {
+    public void onRemoval(RemovalNotification<Key, BytesReference> notification) {
         notification.getKey().entity.onRemoval(notification);
     }
 
-    BytesReference getOrCompute(CacheEntity cacheEntity, DirectoryReader reader, BytesReference cacheKey) throws Exception {
+    BytesReference getOrCompute(CacheEntity cacheEntity, Supplier<BytesReference> loader,
+            DirectoryReader reader, BytesReference cacheKey) throws Exception {
         final Key key =  new Key(cacheEntity, reader.getVersion(), cacheKey);
-        Loader loader = new Loader(cacheEntity);
-        Value value = cache.computeIfAbsent(key, loader);
-        if (loader.isLoaded()) {
+        Loader cacheLoader = new Loader(cacheEntity, loader);
+        BytesReference value = cache.computeIfAbsent(key, cacheLoader);
+        if (cacheLoader.isLoaded()) {
             key.entity.onMiss();
             // see if its the first time we see this reader, and make sure to register a cleanup key
             CleanupKey cleanupKey = new CleanupKey(cacheEntity, reader.getVersion());
@@ -126,16 +127,18 @@ public final class IndicesRequestCache extends AbstractComponent implements Remo
         } else {
             key.entity.onHit();
         }
-        return value.reference;
+        return value;
     }
 
-    private static class Loader implements CacheLoader<Key, Value> {
+    private static class Loader implements CacheLoader<Key, BytesReference> {
 
         private final CacheEntity entity;
+        private final Supplier<BytesReference> loader;
         private boolean loaded;
 
-        Loader(CacheEntity entity) {
+        Loader(CacheEntity entity, Supplier<BytesReference> loader) {
             this.entity = entity;
+            this.loader = loader;
         }
 
         public boolean isLoaded() {
@@ -143,8 +146,8 @@ public final class IndicesRequestCache extends AbstractComponent implements Remo
         }
 
         @Override
-        public Value load(Key key) throws Exception {
-            Value value = entity.loadValue();
+        public BytesReference load(Key key) throws Exception {
+            BytesReference value = loader.get();
             entity.onCached(key, value);
             loaded = true;
             return value;
@@ -154,16 +157,12 @@ public final class IndicesRequestCache extends AbstractComponent implements Remo
     /**
      * Basic interface to make this cache testable.
      */
-    interface CacheEntity {
-        /**
-         * Loads the actual cache value. this is the heavy lifting part.
-         */
-        Value loadValue() throws IOException;
+    interface CacheEntity extends Accountable {
 
         /**
-         * Called after the value was loaded via {@link #loadValue()}
+         * Called after the value was loaded.
          */
-        void onCached(Key key, Value value);
+        void onCached(Key key, BytesReference value);
 
         /**
          * Returns <code>true</code> iff the resource behind this entity is still open ie.
@@ -190,32 +189,12 @@ public final class IndicesRequestCache extends AbstractComponent implements Remo
         /**
          * Called when this entity instance is removed
          */
-        void onRemoval(RemovalNotification<Key, Value> notification);
-    }
-
-
-
-    static class Value implements Accountable {
-        final BytesReference reference;
-        final long ramBytesUsed;
-
-        Value(BytesReference reference, long ramBytesUsed) {
-            this.reference = reference;
-            this.ramBytesUsed = ramBytesUsed;
-        }
-
-        @Override
-        public long ramBytesUsed() {
-            return ramBytesUsed;
-        }
-
-        @Override
-        public Collection<Accountable> getChildResources() {
-            return Collections.emptyList();
-        }
+        void onRemoval(RemovalNotification<Key, BytesReference> notification);
     }
 
     static class Key implements Accountable {
+        private static final long BASE_RAM_BYTES_USED = RamUsageEstimator.shallowSizeOfInstance(Key.class);
+
         public final CacheEntity entity; // use as identity equality
         public final long readerVersion; // use the reader version to now keep a reference to a "short" lived reader until its reaped
         public final BytesReference value;
@@ -228,7 +207,7 @@ public final class IndicesRequestCache extends AbstractComponent implements Remo
 
         @Override
         public long ramBytesUsed() {
-            return RamUsageEstimator.NUM_BYTES_OBJECT_REF + Long.BYTES + value.length();
+            return BASE_RAM_BYTES_USED + entity.ramBytesUsed() + value.length();
         }
 
         @Override

core/src/main/java/org/elasticsearch/indices/IndicesService.java

@@ -23,11 +23,11 @@ import com.carrotsearch.hppc.cursors.ObjectCursor;
 
 import org.apache.logging.log4j.Logger;
 import org.apache.logging.log4j.message.ParameterizedMessage;
-import org.apache.logging.log4j.util.Supplier;
 import org.apache.lucene.index.DirectoryReader;
 import org.apache.lucene.store.LockObtainFailedException;
 import org.apache.lucene.util.CollectionUtil;
 import org.apache.lucene.util.IOUtils;
+import org.apache.lucene.util.RamUsageEstimator;
 import org.elasticsearch.ElasticsearchException;
 import org.elasticsearch.action.admin.indices.stats.CommonStats;
 import org.elasticsearch.action.admin.indices.stats.CommonStatsFlags;
@@ -51,9 +51,11 @@ import org.elasticsearch.common.bytes.BytesArray;
 import org.elasticsearch.common.bytes.BytesReference;
 import org.elasticsearch.common.component.AbstractLifecycleComponent;
 import org.elasticsearch.common.io.FileSystemUtils;
+import org.elasticsearch.common.io.stream.BytesStreamOutput;
 import org.elasticsearch.common.io.stream.NamedWriteableAwareStreamInput;
 import org.elasticsearch.common.io.stream.NamedWriteableRegistry;
 import org.elasticsearch.common.io.stream.StreamInput;
+import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.lease.Releasable;
 import org.elasticsearch.common.settings.ClusterSettings;
 import org.elasticsearch.common.settings.IndexScopedSettings;
@@ -98,7 +100,6 @@ import org.elasticsearch.index.shard.IndexingOperationListener;
 import org.elasticsearch.index.shard.IndexingStats;
 import org.elasticsearch.index.shard.ShardId;
 import org.elasticsearch.index.store.IndexStoreConfig;
-import org.elasticsearch.indices.AbstractIndexShardCacheEntity.Loader;
 import org.elasticsearch.indices.breaker.CircuitBreakerService;
 import org.elasticsearch.indices.cluster.IndicesClusterStateService;
 import org.elasticsearch.indices.fielddata.cache.IndicesFieldDataCache;
@@ -132,8 +133,10 @@ import java.util.concurrent.Executors;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicInteger;
+import java.util.function.Consumer;
 import java.util.function.Function;
 import java.util.function.Predicate;
+import java.util.function.Supplier;
 import java.util.stream.Collectors;
 
 import static java.util.Collections.emptyList;
@@ -1110,7 +1113,7 @@ public class IndicesService extends AbstractLifecycleComponent
         if (shard == null) {
             return;
         }
-        indicesRequestCache.clear(new IndexShardCacheEntity(shard, null));
+        indicesRequestCache.clear(new IndexShardCacheEntity(shard));
         logger.trace("{} explicit cache clear", shard.shardId());
     }
 
@@ -1122,13 +1125,19 @@ public class IndicesService extends AbstractLifecycleComponent
      */
     public void loadIntoContext(ShardSearchRequest request, SearchContext context, QueryPhase queryPhase) throws Exception {
         assert canCache(request, context);
-        final IndexShardCacheEntity entity = new IndexShardCacheEntity(context.indexShard(), out -> {
-            queryPhase.execute(context);
-            context.queryResult().writeToNoId(out);
-        });
         final DirectoryReader directoryReader = context.searcher().getDirectoryReader();
-        final BytesReference bytesReference = indicesRequestCache.getOrCompute(entity, directoryReader, request.cacheKey());
-        if (entity.loadedFromCache()) {
+        
+        boolean[] loadedFromCache = new boolean[] { true };
+        BytesReference bytesReference = cacheShardLevelResult(context.indexShard(), directoryReader, request.cacheKey(), out -> {
+            queryPhase.execute(context);
+            try {
+                context.queryResult().writeToNoId(out);
+            } catch (IOException e) {
+                throw new AssertionError("Could not serialize response", e);
+            }
+            loadedFromCache[0] = false;
+        });
+        if (loadedFromCache[0]) {
             // restore the cached query result into the context
             final QuerySearchResult result = context.queryResult();
             StreamInput in = new NamedWriteableAwareStreamInput(bytesReference.streamInput(), namedWriteableRegistry);
@@ -1154,7 +1163,11 @@ public class IndicesService extends AbstractLifecycleComponent
         }
         BytesReference cacheKey = new BytesArray("fieldstats:" + field);
         BytesReference statsRef = cacheShardLevelResult(shard, searcher.getDirectoryReader(), cacheKey, out -> {
-            out.writeOptionalWriteable(fieldType.stats(searcher.reader()));
+            try {
+                out.writeOptionalWriteable(fieldType.stats(searcher.reader()));
+            } catch (IOException e) {
+                throw new IllegalStateException("Failed to write field stats output", e);
+            }
         });
         try (StreamInput in = statsRef.streamInput()) {
             return in.readOptionalWriteable(FieldStats::readFrom);
@@ -1173,17 +1186,33 @@ public class IndicesService extends AbstractLifecycleComponent
      * @param loader loads the data into the cache if needed
      * @return the contents of the cache or the result of calling the loader
      */
-    private BytesReference cacheShardLevelResult(IndexShard shard, DirectoryReader reader, BytesReference cacheKey, Loader loader)
+    private BytesReference cacheShardLevelResult(IndexShard shard, DirectoryReader reader, BytesReference cacheKey, Consumer<StreamOutput> loader)
             throws Exception {
-        IndexShardCacheEntity cacheEntity = new IndexShardCacheEntity(shard, loader);
-        return indicesRequestCache.getOrCompute(cacheEntity, reader, cacheKey);
+        IndexShardCacheEntity cacheEntity = new IndexShardCacheEntity(shard);
+        Supplier<BytesReference> supplier = () -> {
+            /* BytesStreamOutput allows to pass the expected size but by default uses
+             * BigArrays.PAGE_SIZE_IN_BYTES which is 16k. A common cached result ie.
+             * a date histogram with 3 buckets is ~100byte so 16k might be very wasteful
+             * since we don't shrink to the actual size once we are done serializing.
+             * By passing 512 as the expected size we will resize the byte array in the stream
+             * slowly until we hit the page size and don't waste too much memory for small query
+             * results.*/
+            final int expectedSizeInBytes = 512;
+            try (BytesStreamOutput out = new BytesStreamOutput(expectedSizeInBytes)) {
+                loader.accept(out);
+                // for now, keep the paged data structure, which might have unused bytes to fill a page, but better to keep
+                // the memory properly paged instead of having varied sized bytes
+                return out.bytes();
+            }
+        };
+        return indicesRequestCache.getOrCompute(cacheEntity, supplier, reader, cacheKey);
     }
 
     static final class IndexShardCacheEntity extends AbstractIndexShardCacheEntity {
+        private static final long BASE_RAM_BYTES_USED = RamUsageEstimator.shallowSizeOfInstance(IndexShardCacheEntity.class);
         private final IndexShard indexShard;
 
-        protected IndexShardCacheEntity(IndexShard indexShard, Loader loader) {
-            super(loader);
+        protected IndexShardCacheEntity(IndexShard indexShard) {
             this.indexShard = indexShard;
         }
 
@@ -1201,6 +1230,13 @@ public class IndicesService extends AbstractLifecycleComponent
         public Object getCacheIdentity() {
             return indexShard;
         }
+
+        @Override
+        public long ramBytesUsed() {
+            // No need to take the IndexShard into account since it is shared
+            // across many entities
+            return BASE_RAM_BYTES_USED;
+        }
     }
 
     @FunctionalInterface

core/src/main/java/org/elasticsearch/ingest/IngestMetadata.java

@@ -116,7 +116,7 @@ public final class IngestMetadata implements MetaData.Custom {
 
     @Override
     public EnumSet<MetaData.XContentContext> context() {
-        return MetaData.API_AND_GATEWAY;
+        return MetaData.ALL_CONTEXTS;
     }
 
     @Override

core/src/main/java/org/elasticsearch/monitor/os/OsStats.java

@@ -19,6 +19,7 @@
 
 package org.elasticsearch.monitor.os;
 
+import org.elasticsearch.Version;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.io.stream.Writeable;
@@ -31,7 +32,7 @@ import java.util.Arrays;
 import java.util.Objects;
 
 public class OsStats implements Writeable, ToXContent {
-
+    public static final Version V_5_1_0 = Version.fromId(5010099);
     private final long timestamp;
     private final Cpu cpu;
     private final Mem mem;
@@ -51,7 +52,11 @@ public class OsStats implements Writeable, ToXContent {
         this.cpu = new Cpu(in);
         this.mem = new Mem(in);
         this.swap = new Swap(in);
-        this.cgroup = in.readOptionalWriteable(Cgroup::new);
+        if (in.getVersion().onOrAfter(V_5_1_0)) {
+            this.cgroup = in.readOptionalWriteable(Cgroup::new);
+        } else {
+            this.cgroup = null;
+        }
     }
 
     @Override
@@ -60,7 +65,9 @@ public class OsStats implements Writeable, ToXContent {
         cpu.writeTo(out);
         mem.writeTo(out);
         swap.writeTo(out);
-        out.writeOptionalWriteable(cgroup);
+        if (out.getVersion().onOrAfter(V_5_1_0)) {
+            out.writeOptionalWriteable(cgroup);
+        }
     }
 
     public long getTimestamp() {

core/src/main/java/org/elasticsearch/node/Node.java

@@ -76,6 +76,9 @@ import org.elasticsearch.common.util.BigArrays;
 import org.elasticsearch.discovery.Discovery;
 import org.elasticsearch.discovery.DiscoveryModule;
 import org.elasticsearch.discovery.DiscoverySettings;
+import org.elasticsearch.discovery.zen.UnicastHostsProvider;
+import org.elasticsearch.discovery.zen.UnicastZenPing;
+import org.elasticsearch.discovery.zen.ZenPing;
 import org.elasticsearch.env.Environment;
 import org.elasticsearch.env.NodeEnvironment;
 import org.elasticsearch.gateway.GatewayAllocator;
@@ -319,7 +322,8 @@ public class Node implements Closeable {
             final ClusterService clusterService = new ClusterService(settings, settingsModule.getClusterSettings(), threadPool);
             clusterService.add(scriptModule.getScriptService());
             resourcesToClose.add(clusterService);
-            final TribeService tribeService = new TribeService(settings, clusterService, nodeEnvironment.nodeId(), classpathPlugins);
+            final TribeService tribeService = new TribeService(settings, clusterService, nodeEnvironment.nodeId(),
+                s -> newTribeClientNode(s, classpathPlugins));
             resourcesToClose.add(tribeService);
             final IngestService ingestService = new IngestService(settings, threadPool, this.environment,
                 scriptModule.getScriptService(), analysisModule.getAnalysisRegistry(), pluginsService.filterPlugins(IngestPlugin.class));
@@ -393,7 +397,10 @@ public class Node implements Closeable {
                     b.bind(HttpServer.class).toProvider(Providers.of(null));
                 };
             }
-            modules.add(new DiscoveryModule(this.settings, transportService, networkService, pluginsService.filterPlugins(DiscoveryPlugin.class)));
+            final DiscoveryModule discoveryModule = new DiscoveryModule(this.settings, transportService, networkService,
+                pluginsService.filterPlugins(DiscoveryPlugin.class));
+            final ZenPing zenPing = newZenPing(settings, threadPool, transportService, discoveryModule.getHostsProvider());
+            modules.add(discoveryModule);
             pluginsService.processModules(modules);
             modules.add(b -> {
                     b.bind(IndicesQueriesRegistry.class).toInstance(searchModule.getQueryParserRegistry());
@@ -425,6 +432,7 @@ public class Node implements Closeable {
                     b.bind(UpdateHelper.class).toInstance(new UpdateHelper(settings, scriptModule.getScriptService()));
                     b.bind(MetaDataIndexUpgradeService.class).toInstance(new MetaDataIndexUpgradeService(settings,
                         indicesModule.getMapperRegistry(), settingsModule.getIndexScopedSettings()));
+                    b.bind(ZenPing.class).toInstance(zenPing);
                     {
                         RecoverySettings recoverySettings = new RecoverySettings(settings, settingsModule.getClusterSettings());
                         processRecoverySettings(settingsModule.getClusterSettings(), recoverySettings);
@@ -881,4 +889,15 @@ public class Node implements Closeable {
         }
         return customNameResolvers;
     }
+
+    /** Create a new ZenPing instance for use in zen discovery. */
+    protected ZenPing newZenPing(Settings settings, ThreadPool threadPool, TransportService transportService,
+                                 UnicastHostsProvider hostsProvider) {
+        return new UnicastZenPing(settings, threadPool, transportService, hostsProvider);
+    }
+
+    /** Constructs an internal node used as a client into a cluster fronted by this tribe node. */
+    protected Node newTribeClientNode(Settings settings, Collection<Class<? extends Plugin>> classpathPlugins) {
+        return new Node(new Environment(settings), classpathPlugins);
+    }
 }

core/src/main/java/org/elasticsearch/plugins/RemovePluginCommand.java

@@ -19,6 +19,19 @@
 
 package org.elasticsearch.plugins;
 
+import joptsimple.OptionSet;
+import joptsimple.OptionSpec;
+
+import org.apache.lucene.util.IOUtils;
+import org.elasticsearch.cli.ExitCodes;
+import org.elasticsearch.cli.SettingCommand;
+import org.elasticsearch.cli.Terminal;
+import org.elasticsearch.cli.UserException;
+import org.elasticsearch.common.Strings;
+import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.env.Environment;
+import org.elasticsearch.node.internal.InternalSettingsPreparer;
+
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.StandardCopyOption;
@@ -26,18 +39,6 @@ import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
 
-import joptsimple.OptionSet;
-import joptsimple.OptionSpec;
-import org.apache.lucene.util.IOUtils;
-import org.elasticsearch.cli.ExitCodes;
-import org.elasticsearch.cli.SettingCommand;
-import org.elasticsearch.cli.UserException;
-import org.elasticsearch.common.Strings;
-import org.elasticsearch.cli.Terminal;
-import org.elasticsearch.common.settings.Settings;
-import org.elasticsearch.env.Environment;
-import org.elasticsearch.node.internal.InternalSettingsPreparer;
-
 import static org.elasticsearch.cli.Terminal.Verbosity.VERBOSE;
 
 /**
@@ -67,7 +68,7 @@ final class RemovePluginCommand extends SettingCommand {
         final Path pluginDir = env.pluginsFile().resolve(pluginName);
         if (Files.exists(pluginDir) == false) {
             throw new UserException(
-                    ExitCodes.USAGE,
+                    ExitCodes.CONFIG,
                     "plugin " + pluginName + " not found; run 'elasticsearch-plugin list' to get list of installed plugins");
         }
 

core/src/main/java/org/elasticsearch/rest/action/RestActions.java

@@ -192,7 +192,6 @@ public class RestActions {
         queryBuilder.defaultField(request.param("df"));
         queryBuilder.analyzer(request.param("analyzer"));
         queryBuilder.analyzeWildcard(request.paramAsBoolean("analyze_wildcard", false));
-        queryBuilder.lowercaseExpandedTerms(request.paramAsBoolean("lowercase_expanded_terms", true));
         queryBuilder.lenient(request.paramAsBoolean("lenient", null));
         String defaultOperator = request.param("default_operator");
         if (defaultOperator != null) {

core/src/main/java/org/elasticsearch/rest/action/RestBuilderListener.java

@@ -34,11 +34,22 @@ public abstract class RestBuilderListener<Response> extends RestResponseListener
 
     @Override
     public final RestResponse buildResponse(Response response) throws Exception {
-        return buildResponse(response, channel.newBuilder());
+        try (XContentBuilder builder = channel.newBuilder()) {
+            final RestResponse restResponse = buildResponse(response, builder);
+            assert assertBuilderClosed(builder);
+            return restResponse;
+        }
     }
 
     /**
-     * Builds a response to send back over the channel.
+     * Builds a response to send back over the channel. Implementors should ensure that they close the provided {@link XContentBuilder}
+     * using the {@link XContentBuilder#close()} method.
      */
     public abstract RestResponse buildResponse(Response response, XContentBuilder builder) throws Exception;
+
+    // pkg private method that we can override for testing
+    boolean assertBuilderClosed(XContentBuilder xContentBuilder) {
+        assert xContentBuilder.generator().isClosed() : "callers should ensure the XContentBuilder is closed themselves";
+        return true;
+    }
 }

core/src/main/java/org/elasticsearch/rest/action/admin/indices/RestUpgradeAction.java

@@ -20,9 +20,11 @@
 package org.elasticsearch.rest.action.admin.indices;
 
 import org.elasticsearch.Version;
+import org.elasticsearch.action.admin.indices.upgrade.get.UpgradeStatusRequest;
 import org.elasticsearch.action.admin.indices.upgrade.get.UpgradeStatusResponse;
 import org.elasticsearch.action.admin.indices.upgrade.post.UpgradeRequest;
 import org.elasticsearch.action.admin.indices.upgrade.post.UpgradeResponse;
+import org.elasticsearch.action.support.IndicesOptions;
 import org.elasticsearch.client.node.NodeClient;
 import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.collect.Tuple;
@@ -68,20 +70,22 @@ public class RestUpgradeAction extends BaseRestHandler {
     }
 
     private RestChannelConsumer handleGet(final RestRequest request, NodeClient client) {
-        return channel -> client.admin().indices().prepareUpgradeStatus(Strings.splitStringByCommaToArray(request.param("index")))
-            .execute(new RestBuilderListener<UpgradeStatusResponse>(channel) {
-                @Override
-                public RestResponse buildResponse(UpgradeStatusResponse response, XContentBuilder builder) throws Exception {
-                    builder.startObject();
-                    response.toXContent(builder, request);
-                    builder.endObject();
-                    return new BytesRestResponse(OK, builder);
-                }
-            });
+        UpgradeStatusRequest statusRequest = new UpgradeStatusRequest(Strings.splitStringByCommaToArray(request.param("index")));
+        statusRequest.indicesOptions(IndicesOptions.fromRequest(request, statusRequest.indicesOptions()));
+        return channel -> client.admin().indices().upgradeStatus(statusRequest, new RestBuilderListener<UpgradeStatusResponse>(channel) {
+            @Override
+            public RestResponse buildResponse(UpgradeStatusResponse response, XContentBuilder builder) throws Exception {
+                builder.startObject();
+                response.toXContent(builder, request);
+                builder.endObject();
+                return new BytesRestResponse(OK, builder);
+            }
+        });
     }
 
     private RestChannelConsumer handlePost(final RestRequest request, NodeClient client) {
         UpgradeRequest upgradeReq = new UpgradeRequest(Strings.splitStringByCommaToArray(request.param("index")));
+        upgradeReq.indicesOptions(IndicesOptions.fromRequest(request, upgradeReq.indicesOptions()));
         upgradeReq.upgradeOnlyAncientSegments(request.paramAsBoolean("only_ancient_segments", false));
         return channel -> client.admin().indices().upgrade(upgradeReq, new RestBuilderListener<UpgradeResponse>(channel) {
             @Override

core/src/main/java/org/elasticsearch/rest/action/cat/RestNodesAction.java

@@ -85,7 +85,7 @@ public class RestNodesAction extends AbstractCatAction {
         clusterStateRequest.clear().nodes(true);
         clusterStateRequest.local(request.paramAsBoolean("local", clusterStateRequest.local()));
         clusterStateRequest.masterNodeTimeout(request.paramAsTime("master_timeout", clusterStateRequest.masterNodeTimeout()));
-
+        final boolean fullId = request.paramAsBoolean("full_id", false);
         return channel -> client.admin().cluster().state(clusterStateRequest, new RestActionListener<ClusterStateResponse>(channel) {
             @Override
             public void processResponse(final ClusterStateResponse clusterStateResponse) {
@@ -99,7 +99,8 @@ public class RestNodesAction extends AbstractCatAction {
                         client.admin().cluster().nodesStats(nodesStatsRequest, new RestResponseListener<NodesStatsResponse>(channel) {
                             @Override
                             public RestResponse buildResponse(NodesStatsResponse nodesStatsResponse) throws Exception {
-                                return RestTable.buildResponse(buildTable(request, clusterStateResponse, nodesInfoResponse, nodesStatsResponse), channel);
+                                return RestTable.buildResponse(buildTable(fullId, request, clusterStateResponse, nodesInfoResponse,
+                                    nodesStatsResponse), channel);
                             }
                         });
                     }
@@ -129,7 +130,8 @@ public class RestNodesAction extends AbstractCatAction {
         table.addCell("ram.percent", "alias:rp,ramPercent;text-align:right;desc:used machine memory ratio");
         table.addCell("ram.max", "default:false;alias:rm,ramMax;text-align:right;desc:total machine memory");
         table.addCell("file_desc.current", "default:false;alias:fdc,fileDescriptorCurrent;text-align:right;desc:used file descriptors");
-        table.addCell("file_desc.percent", "default:false;alias:fdp,fileDescriptorPercent;text-align:right;desc:used file descriptor ratio");
+        table.addCell("file_desc.percent",
+            "default:false;alias:fdp,fileDescriptorPercent;text-align:right;desc:used file descriptor ratio");
         table.addCell("file_desc.max", "default:false;alias:fdm,fileDescriptorMax;text-align:right;desc:max file descriptors");
 
         table.addCell("cpu", "alias:cpu;text-align:right;desc:recent cpu usage");
@@ -137,7 +139,8 @@ public class RestNodesAction extends AbstractCatAction {
         table.addCell("load_5m", "alias:l;text-align:right;desc:5m load avg");
         table.addCell("load_15m", "alias:l;text-align:right;desc:15m load avg");
         table.addCell("uptime", "default:false;alias:u;text-align:right;desc:node uptime");
-        table.addCell("node.role", "alias:r,role,nodeRole;desc:m:master eligible node, d:data node, i:ingest node, -:coordinating node only");
+        table.addCell("node.role",
+            "alias:r,role,nodeRole;desc:m:master eligible node, d:data node, i:ingest node, -:coordinating node only");
         table.addCell("master", "alias:m;desc:*:current master");
         table.addCell("name", "alias:n;desc:node name");
 
@@ -150,9 +153,12 @@ public class RestNodesAction extends AbstractCatAction {
         table.addCell("query_cache.evictions", "alias:qce,queryCacheEvictions;default:false;text-align:right;desc:query cache evictions");
 
         table.addCell("request_cache.memory_size", "alias:rcm,requestCacheMemory;default:false;text-align:right;desc:used request cache");
-        table.addCell("request_cache.evictions", "alias:rce,requestCacheEvictions;default:false;text-align:right;desc:request cache evictions");
-        table.addCell("request_cache.hit_count", "alias:rchc,requestCacheHitCount;default:false;text-align:right;desc:request cache hit counts");
-        table.addCell("request_cache.miss_count", "alias:rcmc,requestCacheMissCount;default:false;text-align:right;desc:request cache miss counts");
+        table.addCell("request_cache.evictions",
+            "alias:rce,requestCacheEvictions;default:false;text-align:right;desc:request cache evictions");
+        table.addCell("request_cache.hit_count",
+            "alias:rchc,requestCacheHitCount;default:false;text-align:right;desc:request cache hit counts");
+        table.addCell("request_cache.miss_count",
+            "alias:rcmc,requestCacheMissCount;default:false;text-align:right;desc:request cache miss counts");
 
         table.addCell("flush.total", "alias:ft,flushTotal;default:false;text-align:right;desc:number of flushes");
         table.addCell("flush.total_time", "alias:ftt,flushTotalTime;default:false;text-align:right;desc:time spent in flush");
@@ -165,16 +171,20 @@ public class RestNodesAction extends AbstractCatAction {
         table.addCell("get.missing_time", "alias:gmti,getMissingTime;default:false;text-align:right;desc:time spent in failed gets");
         table.addCell("get.missing_total", "alias:gmto,getMissingTotal;default:false;text-align:right;desc:number of failed gets");
 
-        table.addCell("indexing.delete_current", "alias:idc,indexingDeleteCurrent;default:false;text-align:right;desc:number of current deletions");
+        table.addCell("indexing.delete_current",
+            "alias:idc,indexingDeleteCurrent;default:false;text-align:right;desc:number of current deletions");
         table.addCell("indexing.delete_time", "alias:idti,indexingDeleteTime;default:false;text-align:right;desc:time spent in deletions");
         table.addCell("indexing.delete_total", "alias:idto,indexingDeleteTotal;default:false;text-align:right;desc:number of delete ops");
-        table.addCell("indexing.index_current", "alias:iic,indexingIndexCurrent;default:false;text-align:right;desc:number of current indexing ops");
+        table.addCell("indexing.index_current",
+            "alias:iic,indexingIndexCurrent;default:false;text-align:right;desc:number of current indexing ops");
         table.addCell("indexing.index_time", "alias:iiti,indexingIndexTime;default:false;text-align:right;desc:time spent in indexing");
         table.addCell("indexing.index_total", "alias:iito,indexingIndexTotal;default:false;text-align:right;desc:number of indexing ops");
-        table.addCell("indexing.index_failed", "alias:iif,indexingIndexFailed;default:false;text-align:right;desc:number of failed indexing ops");
+        table.addCell("indexing.index_failed",
+            "alias:iif,indexingIndexFailed;default:false;text-align:right;desc:number of failed indexing ops");
 
         table.addCell("merges.current", "alias:mc,mergesCurrent;default:false;text-align:right;desc:number of current merges");
-        table.addCell("merges.current_docs", "alias:mcd,mergesCurrentDocs;default:false;text-align:right;desc:number of current merging docs");
+        table.addCell("merges.current_docs",
+            "alias:mcd,mergesCurrentDocs;default:false;text-align:right;desc:number of current merging docs");
         table.addCell("merges.current_size", "alias:mcs,mergesCurrentSize;default:false;text-align:right;desc:size of current merges");
         table.addCell("merges.total", "alias:mt,mergesTotal;default:false;text-align:right;desc:number of completed merge ops");
         table.addCell("merges.total_docs", "alias:mtd,mergesTotalDocs;default:false;text-align:right;desc:docs merged");
@@ -185,7 +195,8 @@ public class RestNodesAction extends AbstractCatAction {
         table.addCell("refresh.time", "alias:rti,refreshTime;default:false;text-align:right;desc:time spent in refreshes");
 
         table.addCell("script.compilations", "alias:scrcc,scriptCompilations;default:false;text-align:right;desc:script compilations");
-        table.addCell("script.cache_evictions", "alias:scrce,scriptCacheEvictions;default:false;text-align:right;desc:script cache evictions");
+        table.addCell("script.cache_evictions",
+            "alias:scrce,scriptCacheEvictions;default:false;text-align:right;desc:script cache evictions");
 
         table.addCell("search.fetch_current", "alias:sfc,searchFetchCurrent;default:false;text-align:right;desc:current fetch phase ops");
         table.addCell("search.fetch_time", "alias:sfti,searchFetchTime;default:false;text-align:right;desc:time spent in fetch phase");
@@ -195,14 +206,19 @@ public class RestNodesAction extends AbstractCatAction {
         table.addCell("search.query_time", "alias:sqti,searchQueryTime;default:false;text-align:right;desc:time spent in query phase");
         table.addCell("search.query_total", "alias:sqto,searchQueryTotal;default:false;text-align:right;desc:total query phase ops");
         table.addCell("search.scroll_current", "alias:scc,searchScrollCurrent;default:false;text-align:right;desc:open scroll contexts");
-        table.addCell("search.scroll_time", "alias:scti,searchScrollTime;default:false;text-align:right;desc:time scroll contexts held open");
+        table.addCell("search.scroll_time",
+            "alias:scti,searchScrollTime;default:false;text-align:right;desc:time scroll contexts held open");
         table.addCell("search.scroll_total", "alias:scto,searchScrollTotal;default:false;text-align:right;desc:completed scroll contexts");
 
         table.addCell("segments.count", "alias:sc,segmentsCount;default:false;text-align:right;desc:number of segments");
         table.addCell("segments.memory", "alias:sm,segmentsMemory;default:false;text-align:right;desc:memory used by segments");
-        table.addCell("segments.index_writer_memory", "alias:siwm,segmentsIndexWriterMemory;default:false;text-align:right;desc:memory used by index writer");
-        table.addCell("segments.version_map_memory", "alias:svmm,segmentsVersionMapMemory;default:false;text-align:right;desc:memory used by version map");
-        table.addCell("segments.fixed_bitset_memory", "alias:sfbm,fixedBitsetMemory;default:false;text-align:right;desc:memory used by fixed bit sets for nested object field types and type filters for types referred in _parent fields");
+        table.addCell("segments.index_writer_memory",
+            "alias:siwm,segmentsIndexWriterMemory;default:false;text-align:right;desc:memory used by index writer");
+        table.addCell("segments.version_map_memory",
+            "alias:svmm,segmentsVersionMapMemory;default:false;text-align:right;desc:memory used by version map");
+        table.addCell("segments.fixed_bitset_memory",
+            "alias:sfbm,fixedBitsetMemory;default:false;text-align:right;desc:memory used by fixed bit sets for nested object field types" +
+                " and type filters for types referred in _parent fields");
 
         table.addCell("suggest.current", "alias:suc,suggestCurrent;default:false;text-align:right;desc:number of current suggest ops");
         table.addCell("suggest.time", "alias:suti,suggestTime;default:false;text-align:right;desc:time spend in suggest");
@@ -212,8 +228,8 @@ public class RestNodesAction extends AbstractCatAction {
         return table;
     }
 
-    private Table buildTable(RestRequest req, ClusterStateResponse state, NodesInfoResponse nodesInfo, NodesStatsResponse nodesStats) {
-        boolean fullId = req.paramAsBoolean("full_id", false);
+    private Table buildTable(boolean fullId, RestRequest req, ClusterStateResponse state, NodesInfoResponse nodesInfo,
+                             NodesStatsResponse nodesStats) {
 
         DiscoveryNodes nodes = state.getState().nodes();
         String masterId = nodes.getMasterNodeId();
@@ -255,14 +271,18 @@ public class RestNodesAction extends AbstractCatAction {
             table.addCell(osStats == null ? null : osStats.getMem() == null ? null : osStats.getMem().getUsedPercent());
             table.addCell(osStats == null ? null : osStats.getMem() == null ? null : osStats.getMem().getTotal());
             table.addCell(processStats == null ? null : processStats.getOpenFileDescriptors());
-            table.addCell(processStats == null ? null : calculatePercentage(processStats.getOpenFileDescriptors(), processStats.getMaxFileDescriptors()));
+            table.addCell(processStats == null ? null : calculatePercentage(processStats.getOpenFileDescriptors(),
+                processStats.getMaxFileDescriptors()));
             table.addCell(processStats == null ? null : processStats.getMaxFileDescriptors());
 
             table.addCell(osStats == null ? null : Short.toString(osStats.getCpu().getPercent()));
             boolean hasLoadAverage = osStats != null && osStats.getCpu().getLoadAverage() != null;
-            table.addCell(!hasLoadAverage || osStats.getCpu().getLoadAverage()[0] == -1 ? null : String.format(Locale.ROOT, "%.2f", osStats.getCpu().getLoadAverage()[0]));
-            table.addCell(!hasLoadAverage || osStats.getCpu().getLoadAverage()[1] == -1 ? null : String.format(Locale.ROOT, "%.2f", osStats.getCpu().getLoadAverage()[1]));
-            table.addCell(!hasLoadAverage || osStats.getCpu().getLoadAverage()[2] == -1 ? null : String.format(Locale.ROOT, "%.2f", osStats.getCpu().getLoadAverage()[2]));
+            table.addCell(!hasLoadAverage || osStats.getCpu().getLoadAverage()[0] == -1 ? null :
+                String.format(Locale.ROOT, "%.2f", osStats.getCpu().getLoadAverage()[0]));
+            table.addCell(!hasLoadAverage || osStats.getCpu().getLoadAverage()[1] == -1 ? null :
+                String.format(Locale.ROOT, "%.2f", osStats.getCpu().getLoadAverage()[1]));
+            table.addCell(!hasLoadAverage || osStats.getCpu().getLoadAverage()[2] == -1 ? null :
+                String.format(Locale.ROOT, "%.2f", osStats.getCpu().getLoadAverage()[2]));
             table.addCell(jvmStats == null ? null : jvmStats.getUptime());
 
             final String roles;

core/src/main/java/org/elasticsearch/script/Script.java

@@ -109,7 +109,7 @@ public final class Script implements ToXContent, Writeable {
         boolean hasType = type != null;
         out.writeBoolean(hasType);
         if (hasType) {
-            ScriptType.writeTo(type, out);
+            type.writeTo(out);
         }
         out.writeOptionalString(lang);
         out.writeMap(params);

core/src/main/java/org/elasticsearch/script/ScriptMetaData.java

@@ -131,7 +131,7 @@ public final class ScriptMetaData implements MetaData.Custom {
 
     @Override
     public EnumSet<MetaData.XContentContext> context() {
-        return MetaData.API_AND_GATEWAY;
+        return MetaData.ALL_CONTEXTS;
     }
 
     @Override

core/src/main/java/org/elasticsearch/script/ScriptModes.java

@@ -72,7 +72,7 @@ public class ScriptModes {
     }
 
     static String sourceKey(ScriptType scriptType) {
-        return SCRIPT_SETTINGS_PREFIX + "." + scriptType.getScriptType();
+        return SCRIPT_SETTINGS_PREFIX + "." + scriptType.getName();
     }
 
     static String getGlobalKey(String lang, ScriptType scriptType) {

core/src/main/java/org/elasticsearch/script/ScriptSettings.java

@@ -50,7 +50,7 @@ public class ScriptSettings {
         for (ScriptType scriptType : ScriptType.values()) {
             scriptTypeSettingMap.put(scriptType, Setting.boolSetting(
                 ScriptModes.sourceKey(scriptType),
-                scriptType.getDefaultScriptEnabled(),
+                scriptType.isDefaultEnabled(),
                 Property.NodeScope));
         }
         SCRIPT_TYPE_SETTING_MAP = Collections.unmodifiableMap(scriptTypeSettingMap);
@@ -102,7 +102,7 @@ public class ScriptSettings {
                 boolean defaultLangAndType = defaultNonFileScriptMode;
                 // Files are treated differently because they are never default-deny
                 if (ScriptType.FILE == scriptType) {
-                    defaultLangAndType = ScriptType.FILE.getDefaultScriptEnabled();
+                    defaultLangAndType = ScriptType.FILE.isDefaultEnabled();
                 }
                 final boolean defaultIfNothingSet = defaultLangAndType;
 

core/src/main/java/org/elasticsearch/script/ScriptType.java

@@ -22,68 +22,118 @@ package org.elasticsearch.script;
 import org.elasticsearch.common.ParseField;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
+import org.elasticsearch.common.io.stream.Writeable;
 
 import java.io.IOException;
-import java.util.Locale;
 
 /**
- * The type of a script, more specifically where it gets loaded from:
- * - provided dynamically at request time
- * - loaded from an index
- * - loaded from file
+ * ScriptType represents the way a script is stored and retrieved from the {@link ScriptService}.
+ * It's also used to by {@link ScriptSettings} and {@link ScriptModes} to determine whether or not
+ * a {@link Script} is allowed to be executed based on both default and user-defined settings.
  */
-public enum ScriptType {
+public enum ScriptType implements Writeable {
 
-    INLINE(0, "inline", "inline", false),
-    STORED(1, "id", "stored", false),
-    FILE(2, "file", "file", true);
+    /**
+     * INLINE scripts are specified in numerous queries and compiled on-the-fly.
+     * They will be cached based on the lang and code of the script.
+     * They are turned off by default because most languages are insecure
+     * (Groovy and others), but can be overriden by the specific {@link ScriptEngineService}
+     * if the language is naturally secure (Painless, Mustache, and Expressions).
+     */
+    INLINE ( 0 , new ParseField("inline") , false ),
 
-    private final int val;
-    private final ParseField parseField;
-    private final String scriptType;
-    private final boolean defaultScriptEnabled;
+    /**
+     * STORED scripts are saved as part of the {@link org.elasticsearch.cluster.ClusterState}
+     * based on user requests.  They will be cached when they are first used in a query.
+     * They are turned off by default because most languages are insecure
+     * (Groovy and others), but can be overriden by the specific {@link ScriptEngineService}
+     * if the language is naturally secure (Painless, Mustache, and Expressions).
+     */
+    STORED ( 1 , new ParseField("stored", "id") , false ),
 
+    /**
+     * FILE scripts are loaded from disk either on start-up or on-the-fly depending on
+     * user-defined settings.  They will be compiled and cached as soon as they are loaded
+     * from disk.  They are turned on by default as they should always be safe to execute.
+     */
+    FILE ( 2 , new ParseField("file") , true  );
+
+    /**
+     * Reads an int from the input stream and converts it to a {@link ScriptType}.
+     * @return The ScriptType read from the stream. Throws an {@link IllegalStateException}
+     * if no ScriptType is found based on the id.
+     */
     public static ScriptType readFrom(StreamInput in) throws IOException {
-        int scriptTypeVal = in.readVInt();
-        for (ScriptType type : values()) {
-            if (type.val == scriptTypeVal) {
-                return type;
-            }
-        }
-        throw new IllegalArgumentException("Unexpected value read for ScriptType got [" + scriptTypeVal + "] expected one of ["
-                + INLINE.val + "," + FILE.val + "," + STORED.val + "]");
-    }
+        int id = in.readVInt();
 
-    public static void writeTo(ScriptType scriptType, StreamOutput out) throws IOException{
-        if (scriptType != null) {
-            out.writeVInt(scriptType.val);
+        if (FILE.id == id) {
+            return FILE;
+        } else if (STORED.id == id) {
+            return STORED;
+        } else if (INLINE.id == id) {
+            return INLINE;
         } else {
-            out.writeVInt(INLINE.val); //Default to inline
+            throw new IllegalStateException("Error reading ScriptType id [" + id + "] from stream, expected one of [" +
+                FILE.id + " [" + FILE.parseField.getPreferredName() + "], " +
+                STORED.id + " [" + STORED.parseField.getPreferredName() + "], " +
+                INLINE.id + " [" + INLINE.parseField.getPreferredName() + "]]");
         }
     }
 
-    ScriptType(int val, String name, String scriptType, boolean defaultScriptEnabled) {
-        this.val = val;
-        this.parseField = new ParseField(name);
-        this.scriptType = scriptType;
-        this.defaultScriptEnabled = defaultScriptEnabled;
+    private final int id;
+    private final ParseField parseField;
+    private final boolean defaultEnabled;
+
+    /**
+     * Standard constructor.
+     * @param id A unique identifier for a type that can be read/written to a stream.
+     * @param parseField Specifies the name used to parse input from queries.
+     * @param defaultEnabled Whether or not a {@link ScriptType} can be run by default.
+     */
+    ScriptType(int id, ParseField parseField, boolean defaultEnabled) {
+        this.id = id;
+        this.parseField = parseField;
+        this.defaultEnabled = defaultEnabled;
     }
 
+    public void writeTo(StreamOutput out) throws IOException {
+        out.writeVInt(id);
+    }
+
+    /**
+     * @return The unique id for this {@link ScriptType}.
+     */
+    public int getId() {
+        return id;
+    }
+
+    /**
+     * @return The unique name for this {@link ScriptType} based on the {@link ParseField}.
+     */
+    public String getName() {
+        return parseField.getPreferredName();
+    }
+
+    /**
+     * @return Specifies the name used to parse input from queries.
+     */
     public ParseField getParseField() {
         return parseField;
     }
 
-    public boolean getDefaultScriptEnabled() {
-        return defaultScriptEnabled;
-    }
-
-    public String getScriptType() {
-        return scriptType;
+    /**
+     * @return Whether or not a {@link ScriptType} can be run by default.  Note
+     * this can be potentially overriden by any {@link ScriptEngineService}.
+     */
+    public boolean isDefaultEnabled() {
+        return defaultEnabled;
     }
 
+    /**
+     * @return The same as calling {@link #getName()}.
+     */
     @Override
     public String toString() {
-        return name().toLowerCase(Locale.ROOT);
+        return getName();
     }
-
 }