Refactors WrapperQueryBuilder and Parser

Relates to #10217
Closes #12037

This PR is against the query-refactoring branch.

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

@@ -556,8 +556,8 @@ public abstract class QueryBuilders {
     /**
      * A Query builder which allows building a query thanks to a JSON string or binary data.
      */
-    public static WrapperQueryBuilder wrapperQuery(byte[] source, int offset, int length) {
-        return new WrapperQueryBuilder(source, offset, length);
+    public static WrapperQueryBuilder wrapperQuery(byte[] source) {
+        return new WrapperQueryBuilder(source);
     }
 
     /**

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

@@ -20,11 +20,16 @@
 package org.elasticsearch.index.query;
 
 import com.google.common.base.Charsets;
-
+import org.apache.lucene.search.Query;
 import org.elasticsearch.common.bytes.BytesReference;
+import org.elasticsearch.common.io.stream.StreamInput;
+import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.xcontent.XContentBuilder;
+import org.elasticsearch.common.xcontent.XContentFactory;
+import org.elasticsearch.common.xcontent.XContentParser;
 
 import java.io.IOException;
+import java.util.Arrays;
 
 /**
  * A Query builder which allows building a query given JSON string or binary data provided as input. This is useful when you want
@@ -44,26 +49,20 @@ public class WrapperQueryBuilder extends AbstractQueryBuilder<WrapperQueryBuilde
 
     public static final String NAME = "wrapper";
     private final byte[] source;
-    private final int offset;
-    private final int length;
-    static final WrapperQueryBuilder PROTOTYPE = new WrapperQueryBuilder(null, -1, -1);
+    static final WrapperQueryBuilder PROTOTYPE = new WrapperQueryBuilder((byte[]) null);
 
     /**
      * Creates a query builder given a query provided as a string
      */
     public WrapperQueryBuilder(String source) {
         this.source = source.getBytes(Charsets.UTF_8);
-        this.offset = 0;
-        this.length = this.source.length;
     }
 
     /**
      * Creates a query builder given a query provided as a bytes array
      */
-    public WrapperQueryBuilder(byte[] source, int offset, int length) {
+    public WrapperQueryBuilder(byte[] source) {
         this.source = source;
-        this.offset = offset;
-        this.length = length;
     }
 
     /**
@@ -71,14 +70,21 @@ public class WrapperQueryBuilder extends AbstractQueryBuilder<WrapperQueryBuilde
      */
     public WrapperQueryBuilder(BytesReference source) {
         this.source = source.array();
-        this.offset = source.arrayOffset();
-        this.length = source.length();
+    }
+
+    public byte[] source() {
+        return this.source;
+    }
+
+    @Override
+    public String getName() {
+        return NAME;
     }
 
     @Override
     protected void doXContent(XContentBuilder builder, Params params) throws IOException {
         builder.startObject(NAME);
-        builder.field("query", source, offset, length);
+        builder.field("query", source);
         builder.endObject();
     }
 
@@ -86,4 +92,43 @@ public class WrapperQueryBuilder extends AbstractQueryBuilder<WrapperQueryBuilde
     public String getWriteableName() {
         return NAME;
     }
+
+    @Override
+    protected Query doToQuery(QueryShardContext context) throws IOException {
+        try (XContentParser qSourceParser = XContentFactory.xContent(source).createParser(source)) {
+            final QueryParseContext parseContext = new QueryParseContext(context);
+            parseContext.reset(qSourceParser);
+            QueryBuilder queryBuilder = parseContext.parseInnerQueryBuilder();
+            return queryBuilder.toQuery(context);
+        }
+    }
+
+    @Override
+    public QueryValidationException validate() {
+        QueryValidationException validationException = null;
+        if (this.source == null || this.source.length == 0) {
+            validationException = addValidationError("query source text cannot be null or empty", validationException);
+        }
+        return validationException;
+    }
+
+    @Override
+    protected WrapperQueryBuilder doReadFrom(StreamInput in) throws IOException {
+        return new WrapperQueryBuilder(in.readByteArray());
+    }
+
+    @Override
+    protected void doWriteTo(StreamOutput out) throws IOException {
+        out.writeByteArray(this.source);
+    }
+
+    @Override
+    protected int doHashCode() {
+        return Arrays.hashCode(source);
+    }
+
+    @Override
+    protected boolean doEquals(WrapperQueryBuilder other) {
+        return Arrays.equals(source, other.source);   // otherwise we compare pointers
+    }
 }

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

@@ -19,9 +19,7 @@
 
 package org.elasticsearch.index.query;
 
-import org.apache.lucene.search.Query;
 import org.elasticsearch.common.inject.Inject;
-import org.elasticsearch.common.xcontent.XContentFactory;
 import org.elasticsearch.common.xcontent.XContentParser;
 
 import java.io.IOException;
@@ -29,7 +27,7 @@ import java.io.IOException;
 /**
  * Query parser for JSON Queries.
  */
-public class WrapperQueryParser extends BaseQueryParserTemp {
+public class WrapperQueryParser extends BaseQueryParser {
 
     @Inject
     public WrapperQueryParser() {
@@ -41,8 +39,7 @@ public class WrapperQueryParser extends BaseQueryParserTemp {
     }
 
     @Override
-    public Query parse(QueryShardContext context) throws IOException, QueryParsingException {
-        QueryParseContext parseContext = context.parseContext();
+    public QueryBuilder fromXContent(QueryParseContext parseContext) throws IOException, QueryParsingException {
         XContentParser parser = parseContext.parser();
 
         XContentParser.Token token = parser.nextToken();
@@ -55,15 +52,14 @@ public class WrapperQueryParser extends BaseQueryParserTemp {
         }
         parser.nextToken();
 
-        byte[] querySource = parser.binaryValue();
-        try (XContentParser qSourceParser = XContentFactory.xContent(querySource).createParser(querySource)) {
-            final QueryShardContext contextCopy = new QueryShardContext(context.index(), context.indexQueryParserService());
-            contextCopy.reset(qSourceParser);
-            Query result = contextCopy.parseContext().parseInnerQuery();
-            parser.nextToken();
-            context.combineNamedQueries(contextCopy);
-            return result;
+        byte[] source = parser.binaryValue();
+
+        parser.nextToken();
+
+        if (source == null) {
+            throw new QueryParsingException(parseContext, "wrapper query has no [query] specified");
         }
+        return new WrapperQueryBuilder(source);
     }
 
     @Override

core/src/test/java/org/elasticsearch/index/query/WrapperQueryBuilderTest.java

@@ -0,0 +1,75 @@
+/*
+ * 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.index.query;
+
+import org.apache.lucene.search.Query;
+import org.elasticsearch.common.xcontent.XContentFactory;
+import org.elasticsearch.common.xcontent.XContentParser;
+import org.junit.Test;
+
+import java.io.IOException;
+
+import static org.hamcrest.Matchers.equalTo;
+import static org.hamcrest.Matchers.is;
+
+public class WrapperQueryBuilderTest extends BaseQueryTestCase<WrapperQueryBuilder> {
+
+    @Override
+    protected boolean supportsBoostAndQueryName() {
+        return false;
+    }
+
+    @Override
+    protected WrapperQueryBuilder doCreateTestQueryBuilder() {
+        QueryBuilder wrappedQuery = RandomQueryBuilder.createQuery(random());
+        switch (randomInt(2)) {
+            case 0:
+                return new WrapperQueryBuilder(wrappedQuery.toString());
+            case 1:
+                return new WrapperQueryBuilder(wrappedQuery.buildAsBytes().toBytes());
+            case 2:
+                return new WrapperQueryBuilder(wrappedQuery.buildAsBytes());
+            default:
+                throw new UnsupportedOperationException();
+        }
+    }
+
+    @Override
+    protected void doAssertLuceneQuery(WrapperQueryBuilder queryBuilder, Query query, QueryShardContext context) throws IOException {
+        try (XContentParser qSourceParser = XContentFactory.xContent(queryBuilder.source()).createParser(queryBuilder.source())) {
+            final QueryParseContext parseContext = new QueryParseContext(context);
+            parseContext.reset(qSourceParser);
+            Query expected = parseContext.parseInnerQueryBuilder().toQuery(context);
+            if (expected != null) {
+                expected.setBoost(AbstractQueryBuilder.DEFAULT_BOOST);
+            }
+            assertThat(query, equalTo(expected));
+        }
+    }
+
+    @Test
+    public void testValidate() {
+        WrapperQueryBuilder wrapperQueryBuilder = new WrapperQueryBuilder((byte[]) null);
+        assertThat(wrapperQueryBuilder.validate().validationErrors().size(), is(1));
+
+        wrapperQueryBuilder = new WrapperQueryBuilder("");
+        assertThat(wrapperQueryBuilder.validate().validationErrors().size(), is(1));
+    }
+}

docs/reference/migration/migrate_query_refactoring.asciidoc

@@ -53,6 +53,12 @@ Removed the setter `queryName(String queryName)` since this field is not support
 in this type of query. Use `FQueryFilterBuilder.queryName(String queryName)` instead 
 when in need to wrap a named query as a filter.
 
+==== WrapperQueryBuilder
+
+Removed `wrapperQueryBuilder(byte[] source, int offset, int length)`. Instead simply
+use  `wrapperQueryBuilder(byte[] source)`. Updated the static factory methods in
+QueryBuilders accordingly.
+
 ==== Operator
 
 Removed the enums called `Operator` from `MatchQueryBuilder`, `QueryStringQueryBuilder`,