Improve error message if a setting is not found (#18920)

Today we only emit that the setting wasn't found unless we have
some DYM suggestions. Yet, if a setting is not found at all and there
are no suggestions due to typos it's likely a removed setting or the plugin
that is supposed to be configured is not installed.
This commit adds some info text to the exception to help the user debugging
the problem before opening bugreports.

Instead of emitting:

`unknown setting [foo.bar]`

we now emit:

`unknown setting [foo.bar] please check the migration guide for removed settings and ensure that the plugin you are configuring is installed`

Relates to #18663

buildSrc/src/main/resources/checkstyle_suppressions.xml

@@ -712,7 +712,6 @@
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]admin[/\\]cluster[/\\]stats[/\\]ClusterStatsIT.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]admin[/\\]indices[/\\]TransportAnalyzeActionTests.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]admin[/\\]indices[/\\]cache[/\\]clear[/\\]ClearIndicesCacheBlocksIT.java" checks="LineLength" />
-  <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]admin[/\\]indices[/\\]create[/\\]CreateIndexIT.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]admin[/\\]indices[/\\]flush[/\\]SyncedFlushUnitTests.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]admin[/\\]indices[/\\]get[/\\]GetIndexIT.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]admin[/\\]indices[/\\]shards[/\\]IndicesShardStoreRequestIT.java" checks="LineLength" />
@@ -1022,7 +1021,6 @@
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]indices[/\\]state[/\\]CloseIndexDisableCloseAllIT.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]indices[/\\]state[/\\]OpenCloseIndexIT.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]indices[/\\]state[/\\]RareClusterStateIT.java" checks="LineLength" />
-  <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]indices[/\\]state[/\\]SimpleIndexStateIT.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]indices[/\\]stats[/\\]IndexStatsIT.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]indices[/\\]store[/\\]IndicesStoreIntegrationIT.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]indices[/\\]store[/\\]IndicesStoreTests.java" checks="LineLength" />

core/src/main/java/org/elasticsearch/common/settings/AbstractScopedSettings.java

@@ -263,6 +263,9 @@ public abstract class AbstractScopedSettings extends AbstractComponent {
             List<String> keys = scoredKeys.stream().map((a) -> a.v2()).collect(Collectors.toList());
             if (keys.isEmpty() == false) {
                 msg += " did you mean " + (keys.size() == 1 ? "[" + keys.get(0) + "]": "any of " + keys.toString()) + "?";
+            } else {
+                msg += " please check that any required plugins are installed, or check the breaking changes documentation for removed " +
+                    "settings";
             }
             throw new IllegalArgumentException(msg);
         }

core/src/test/java/org/elasticsearch/action/admin/indices/create/CreateIndexIT.java

@@ -70,7 +70,8 @@ public class CreateIndexIT extends ESIntegTestCase {
             prepareCreate("test").setSettings(Settings.builder().put(IndexMetaData.SETTING_CREATION_DATE, 4L)).get();
             fail();
         } catch (IllegalArgumentException ex) {
-            assertEquals("unknown setting [index.creation_date]", ex.getMessage());
+            assertEquals("unknown setting [index.creation_date] please check that any required plugins are installed, or check the " +
+                "breaking changes documentation for removed settings", ex.getMessage());
         }
     }
 
@@ -165,7 +166,8 @@ public class CreateIndexIT extends ESIntegTestCase {
                 .get();
             fail("should have thrown an exception about the shard count");
         } catch (IllegalArgumentException e) {
-            assertEquals("unknown setting [index.unknown.value]", e.getMessage());
+            assertEquals("unknown setting [index.unknown.value] please check that any required plugins are installed, or check the" +
+                " breaking changes documentation for removed settings", e.getMessage());
         }
     }
 
@@ -211,13 +213,16 @@ public class CreateIndexIT extends ESIntegTestCase {
                      @Override
                     public void run() {
                          try {
-                             client().prepareIndex("test", "test").setSource("index_version", indexVersion.get()).get(); // recreate that index
+                             // recreate that index
+                             client().prepareIndex("test", "test").setSource("index_version", indexVersion.get()).get();
                              synchronized (indexVersionLock) {
-                                 // we sync here since we have to ensure that all indexing operations below for a given ID are done before we increment the
-                                 // index version otherwise a doc that is in-flight could make it into an index that it was supposed to be deleted for and our assertion fail...
+                                 // we sync here since we have to ensure that all indexing operations below for a given ID are done before
+                                 // we increment the index version otherwise a doc that is in-flight could make it into an index that it
+                                 // was supposed to be deleted for and our assertion fail...
                                  indexVersion.incrementAndGet();
                              }
-                             assertAcked(client().admin().indices().prepareDelete("test").get()); // from here on all docs with index_version == 0|1 must be gone!!!! only 2 are ok;
+                             // from here on all docs with index_version == 0|1 must be gone!!!! only 2 are ok;
+                             assertAcked(client().admin().indices().prepareDelete("test").get());
                          } finally {
                              latch.countDown();
                          }
@@ -249,8 +254,10 @@ public class CreateIndexIT extends ESIntegTestCase {
         latch.await();
         refresh();
 
-        // we only really assert that we never reuse segments of old indices or anything like this here and that nothing fails with crazy exceptions
-        SearchResponse expected = client().prepareSearch("test").setIndicesOptions(IndicesOptions.lenientExpandOpen()).setQuery(new RangeQueryBuilder("index_version").from(indexVersion.get(), true)).get();
+        // we only really assert that we never reuse segments of old indices or anything like this here and that nothing fails with
+        // crazy exceptions
+        SearchResponse expected = client().prepareSearch("test").setIndicesOptions(IndicesOptions.lenientExpandOpen())
+            .setQuery(new RangeQueryBuilder("index_version").from(indexVersion.get(), true)).get();
         SearchResponse all = client().prepareSearch("test").setIndicesOptions(IndicesOptions.lenientExpandOpen()).get();
         assertEquals(expected + " vs. " + all, expected.getHits().getTotalHits(), all.getHits().getTotalHits());
         logger.info("total: {}", expected.getHits().getTotalHits());
@@ -283,7 +290,8 @@ public class CreateIndexIT extends ESIntegTestCase {
     }
 
     public void testRestartIndexCreationAfterFullClusterRestart() throws Exception {
-        client().admin().cluster().prepareUpdateSettings().setTransientSettings(Settings.builder().put("cluster.routing.allocation.enable", "none")).get();
+        client().admin().cluster().prepareUpdateSettings().setTransientSettings(Settings.builder().put("cluster.routing.allocation.enable",
+            "none")).get();
         client().admin().indices().prepareCreate("test").setSettings(indexSettings()).get();
         internalCluster().fullRestart();
         ensureGreen("test");

core/src/test/java/org/elasticsearch/common/settings/ScopedSettingsTests.java

@@ -202,20 +202,22 @@ public class ScopedSettingsTests extends ESTestCase {
         IndexScopedSettings settings = new IndexScopedSettings(
             Settings.EMPTY,
             IndexScopedSettings.BUILT_IN_INDEX_SETTINGS);
+        String unknownMsgSuffix = " please check that any required plugins are installed, or check the breaking changes documentation for" +
+            " removed settings";
         settings.validate(Settings.builder().put("index.store.type", "boom"));
         settings.validate(Settings.builder().put("index.store.type", "boom").build());
         try {
             settings.validate(Settings.builder().put("index.store.type", "boom", "i.am.not.a.setting", true));
             fail();
         } catch (IllegalArgumentException e) {
-            assertEquals("unknown setting [i.am.not.a.setting]", e.getMessage());
+            assertEquals("unknown setting [i.am.not.a.setting]" + unknownMsgSuffix, e.getMessage());
         }
 
         try {
             settings.validate(Settings.builder().put("index.store.type", "boom", "i.am.not.a.setting", true).build());
             fail();
         } catch (IllegalArgumentException e) {
-            assertEquals("unknown setting [i.am.not.a.setting]", e.getMessage());
+            assertEquals("unknown setting [i.am.not.a.setting]" + unknownMsgSuffix, e.getMessage());
         }
 
         try {

core/src/test/java/org/elasticsearch/common/settings/SettingsModuleTests.java

@@ -51,7 +51,8 @@ public class SettingsModuleTests extends ModuleTestCase {
                 () -> new SettingsModule(settings));
             assertEquals("Failed to parse value [[2.0]] for setting [cluster.routing.allocation.balance.shard]", ex.getMessage());
             assertEquals(1, ex.getSuppressed().length);
-            assertEquals("unknown setting [some.foo.bar]", ex.getSuppressed()[0].getMessage());
+            assertEquals("unknown setting [some.foo.bar] please check that any required plugins are installed, or check the breaking " +
+                "changes documentation for removed settings", ex.getSuppressed()[0].getMessage());
         }
 
         {
@@ -127,7 +128,8 @@ public class SettingsModuleTests extends ModuleTestCase {
                 new SettingsModule(settings);
                 fail();
             } catch (IllegalArgumentException ex) {
-                assertEquals("tribe.blocks validation failed: unknown setting [wtf]", ex.getMessage());
+                assertEquals("tribe.blocks validation failed: unknown setting [wtf] please check that any required plugins are" +
+                    " installed, or check the breaking changes documentation for removed settings", ex.getMessage());
             }
         }
     }

core/src/test/java/org/elasticsearch/indices/state/SimpleIndexStateIT.java

@@ -56,7 +56,8 @@ public class SimpleIndexStateIT extends ESIntegTestCase {
         ClusterStateResponse stateResponse = client().admin().cluster().prepareState().get();
         assertThat(stateResponse.getState().metaData().index("test").getState(), equalTo(IndexMetaData.State.OPEN));
         assertThat(stateResponse.getState().routingTable().index("test").shards().size(), equalTo(numShards.numPrimaries));
-        assertThat(stateResponse.getState().routingTable().index("test").shardsWithState(ShardRoutingState.STARTED).size(), equalTo(numShards.totalNumShards));
+        assertEquals(stateResponse.getState().routingTable().index("test").shardsWithState(ShardRoutingState.STARTED).size()
+            , numShards.totalNumShards);
 
         logger.info("--> indexing a simple document");
         client().prepareIndex("test", "type1", "1").setSource("field1", "value1").get();
@@ -88,7 +89,8 @@ public class SimpleIndexStateIT extends ESIntegTestCase {
         assertThat(stateResponse.getState().metaData().index("test").getState(), equalTo(IndexMetaData.State.OPEN));
 
         assertThat(stateResponse.getState().routingTable().index("test").shards().size(), equalTo(numShards.numPrimaries));
-        assertThat(stateResponse.getState().routingTable().index("test").shardsWithState(ShardRoutingState.STARTED).size(), equalTo(numShards.totalNumShards));
+        assertEquals(stateResponse.getState().routingTable().index("test").shardsWithState(ShardRoutingState.STARTED).size(),
+            numShards.totalNumShards);
 
         logger.info("--> indexing a simple document");
         client().prepareIndex("test", "type1", "1").setSource("field1", "value1").get();
@@ -119,7 +121,8 @@ public class SimpleIndexStateIT extends ESIntegTestCase {
         ClusterStateResponse stateResponse = client().admin().cluster().prepareState().get();
         assertThat(stateResponse.getState().metaData().index("test").getState(), equalTo(IndexMetaData.State.OPEN));
         assertThat(stateResponse.getState().routingTable().index("test").shards().size(), equalTo(numShards.numPrimaries));
-        assertThat(stateResponse.getState().routingTable().index("test").shardsWithState(ShardRoutingState.STARTED).size(), equalTo(numShards.totalNumShards));
+        assertEquals(stateResponse.getState().routingTable().index("test").shardsWithState(ShardRoutingState.STARTED).size(),
+            numShards.totalNumShards);
 
         logger.info("--> indexing a simple document");
         client().prepareIndex("test", "type1", "1").setSource("field1", "value1").get();
@@ -143,7 +146,8 @@ public class SimpleIndexStateIT extends ESIntegTestCase {
         }
 
         logger.info("--> creating test index with valid settings ");
-        CreateIndexResponse response = client().admin().indices().prepareCreate("test").setSettings(Settings.builder().put("number_of_shards", 1)).get();
+        CreateIndexResponse response = client().admin().indices().prepareCreate("test")
+            .setSettings(Settings.builder().put("number_of_shards", 1)).get();
         assertThat(response.isAcknowledged(), equalTo(true));
     }
 }

core/src/test/java/org/elasticsearch/indices/template/SimpleIndexTemplateIT.java

@@ -322,7 +322,8 @@ public class SimpleIndexTemplateIT extends ESIntegTestCase {
                 .setTemplate("te*")
                 .setSettings(Settings.builder().put("does_not_exist", "test"))
                 .get());
-        assertEquals("unknown setting [index.does_not_exist]", e.getMessage());
+        assertEquals("unknown setting [index.does_not_exist] please check that any required plugins are" +
+            " installed, or check the breaking changes documentation for removed settings", e.getMessage());
 
         response = client().admin().indices().prepareGetTemplates().get();
         assertEquals(0, response.getIndexTemplates().size());