earch API: Automatically identify "script" fields on the field elements in search, close #357.

modules/elasticsearch/src/main/java/org/elasticsearch/search/fetch/FetchPhase.java

@@ -135,7 +135,7 @@ public class FetchPhase implements SearchPhase {
                 hitField.values().add(value);
             }
 
-            if (context.scriptFields() != null) {
+            if (context.hasScriptFields()) {
                 sameDocCache.clear();
                 int readerIndex = context.searcher().readerIndex(docId);
                 IndexReader subReader = context.searcher().subReaders()[readerIndex];
@@ -203,12 +203,12 @@ public class FetchPhase implements SearchPhase {
     }
 
     private FieldSelector buildFieldSelectors(SearchContext context) {
-        if (context.scriptFields() != null && context.fieldNames() == null) {
+        if (context.hasScriptFields() && !context.hasFieldNames()) {
             // we ask for script fields, and no field names, don't load the source
             return UidFieldSelector.INSTANCE;
         }
 
-        if (context.fieldNames() == null) {
+        if (!context.hasFieldNames()) {
             return new UidAndSourceFieldSelector();
         }
 

modules/elasticsearch/src/main/java/org/elasticsearch/search/fetch/FieldsParseElement.java

@@ -19,13 +19,12 @@
 
 package org.elasticsearch.search.fetch;
 
-import org.elasticsearch.common.collect.ImmutableList;
 import org.elasticsearch.common.xcontent.XContentParser;
+import org.elasticsearch.index.field.function.script.ScriptFieldsFunction;
 import org.elasticsearch.search.SearchParseElement;
+import org.elasticsearch.search.fetch.script.ScriptFieldsContext;
 import org.elasticsearch.search.internal.SearchContext;
 
-import java.util.ArrayList;
-
 /**
  * @author kimchy (shay.banon)
  */
@@ -34,17 +33,28 @@ public class FieldsParseElement implements SearchParseElement {
     @Override public void parse(XContentParser parser, SearchContext context) throws Exception {
         XContentParser.Token token = parser.currentToken();
         if (token == XContentParser.Token.START_ARRAY) {
-            ArrayList<String> fieldNames = new ArrayList<String>();
+            boolean added = false;
             while ((token = parser.nextToken()) != XContentParser.Token.END_ARRAY) {
-                fieldNames.add(parser.text());
+                added = true;
+                String name = parser.text();
+                if (name.contains("_source.") || name.contains("doc[")) {
+                    // script field to load from source
+                    context.scriptFields().add(new ScriptFieldsContext.ScriptField(name, new ScriptFieldsFunction(name, context.scriptService(), context.mapperService(), context.fieldDataCache()), null));
+                } else {
+                    context.fieldNames().add(name);
+                }
             }
-            if (fieldNames.isEmpty()) {
+            if (!added) {
-                context.fieldNames(ImmutableList.<String>of());
+                context.emptyFieldNames();
-            } else {
-                context.fieldNames(fieldNames);
             }
         } else if (token == XContentParser.Token.VALUE_STRING) {
-            context.fieldNames(ImmutableList.of(parser.text()));
+            String name = parser.text();
+            if (name.contains("_source.") || name.contains("doc[")) {
+                // script field to load from source
+                context.scriptFields().add(new ScriptFieldsContext.ScriptField(name, new ScriptFieldsFunction(name, context.scriptService(), context.mapperService(), context.fieldDataCache()), null));
+            } else {
+                context.fieldNames().add(name);
+            }
         }
     }
 }

modules/elasticsearch/src/main/java/org/elasticsearch/search/fetch/script/ScriptFieldsContext.java

@@ -19,6 +19,7 @@
 
 package org.elasticsearch.search.fetch.script;
 
+import org.elasticsearch.common.collect.Lists;
 import org.elasticsearch.index.field.function.script.ScriptFieldsFunction;
 
 import java.util.List;
@@ -53,10 +54,13 @@ public class ScriptFieldsContext {
         }
     }
 
-    private List<ScriptField> fields;
+    private List<ScriptField> fields = Lists.newArrayList();
 
-    public ScriptFieldsContext(List<ScriptField> fields) {
+    public ScriptFieldsContext() {
-        this.fields = fields;
+    }
+
+    public void add(ScriptField field) {
+        this.fields.add(field);
     }
 
     public List<ScriptField> fields() {

modules/elasticsearch/src/main/java/org/elasticsearch/search/fetch/script/ScriptFieldsParseElement.java

@@ -19,14 +19,11 @@
 
 package org.elasticsearch.search.fetch.script;
 
-import org.elasticsearch.common.collect.Lists;
 import org.elasticsearch.common.xcontent.XContentParser;
 import org.elasticsearch.index.field.function.script.ScriptFieldsFunction;
 import org.elasticsearch.search.SearchParseElement;
 import org.elasticsearch.search.internal.SearchContext;
 
-import java.util.HashMap;
-import java.util.List;
 import java.util.Map;
 
 /**
@@ -48,7 +45,6 @@ public class ScriptFieldsParseElement implements SearchParseElement {
     @Override public void parse(XContentParser parser, SearchContext context) throws Exception {
         XContentParser.Token token;
         String currentFieldName = null;
-        List<ScriptFieldsContext.ScriptField> scriptFields = Lists.newArrayList();
         while ((token = parser.nextToken()) != XContentParser.Token.END_OBJECT) {
             if (token == XContentParser.Token.FIELD_NAME) {
                 currentFieldName = parser.currentName();
@@ -65,11 +61,8 @@ public class ScriptFieldsParseElement implements SearchParseElement {
                         script = parser.text();
                     }
                 }
-                scriptFields.add(new ScriptFieldsContext.ScriptField(fieldName,
+                context.scriptFields().add(new ScriptFieldsContext.ScriptField(fieldName, new ScriptFieldsFunction(script, context.scriptService(), context.mapperService(), context.fieldDataCache()), params));
-                        new ScriptFieldsFunction(script, context.scriptService(), context.mapperService(), context.fieldDataCache()),
-                        params == null ? new HashMap<String, Object>() : params));
             }
         }
-        context.scriptFields(new ScriptFieldsContext(scriptFields));
     }
 }

modules/elasticsearch/src/main/java/org/elasticsearch/search/internal/SearchContext.java

@@ -22,6 +22,8 @@ package org.elasticsearch.search.internal;
 import org.apache.lucene.search.Query;
 import org.apache.lucene.search.Sort;
 import org.elasticsearch.ElasticSearchException;
+import org.elasticsearch.common.collect.ImmutableList;
+import org.elasticsearch.common.collect.Lists;
 import org.elasticsearch.common.lease.Releasable;
 import org.elasticsearch.common.timer.Timeout;
 import org.elasticsearch.common.unit.TimeValue;
@@ -198,12 +200,15 @@ public class SearchContext implements Releasable {
         this.highlight = highlight;
     }
 
-    public ScriptFieldsContext scriptFields() {
+    public boolean hasScriptFields() {
-        return this.scriptFields;
+        return scriptFields != null;
     }
 
-    public void scriptFields(ScriptFieldsContext scriptFields) {
+    public ScriptFieldsContext scriptFields() {
-        this.scriptFields = scriptFields;
+        if (scriptFields == null) {
+            scriptFields = new ScriptFieldsContext();
+        }
+        return this.scriptFields;
     }
 
     public ContextIndexSearcher searcher() {
@@ -322,13 +327,19 @@ public class SearchContext implements Releasable {
         return this;
     }
 
+    public boolean hasFieldNames() {
+        return fieldNames != null;
+    }
+
     public List<String> fieldNames() {
+        if (fieldNames == null) {
+            fieldNames = Lists.newArrayList();
+        }
         return fieldNames;
     }
 
-    public SearchContext fieldNames(List<String> fieldNames) {
+    public void emptyFieldNames() {
-        this.fieldNames = fieldNames;
+        this.fieldNames = ImmutableList.of();
-        return this;
     }
 
     public boolean explain() {

modules/test/integration/src/test/java/org/elasticsearch/test/integration/search/scriptfield/ScriptFieldSearchTests.java

@@ -126,13 +126,18 @@ public class ScriptFieldSearchTests extends AbstractNodesTests {
 
         SearchResponse response = client.prepareSearch()
                 .setQuery(matchAllQuery())
+                .addField("_source.obj1") // we also automatically detect _source in fields
                 .addScriptField("s_obj1", "_source.obj1")
                 .addScriptField("s_obj1_test", "_source.obj1.test")
                 .addScriptField("s_obj2", "_source.obj2")
                 .addScriptField("s_obj2_arr2", "_source.obj2.arr2")
                 .execute().actionGet();
 
-        Map<String, Object> sObj1 = (Map<String, Object>) response.hits().getAt(0).field("s_obj1").value();
+        Map<String, Object> sObj1 = (Map<String, Object>) response.hits().getAt(0).field("_source.obj1").value();
+        assertThat(sObj1.get("test").toString(), equalTo("something"));
+        assertThat(response.hits().getAt(0).field("s_obj1_test").value().toString(), equalTo("something"));
+
+        sObj1 = (Map<String, Object>) response.hits().getAt(0).field("s_obj1").value();
         assertThat(sObj1.get("test").toString(), equalTo("something"));
         assertThat(response.hits().getAt(0).field("s_obj1_test").value().toString(), equalTo("something"));