HSEARCH-2603 Use the painless scripting language with Elasticsearch 5+

Because groovy has been deprecated, because painless doesn't require
any server-side configuration, and because only painless is supported on
Amazon Web Services.

elasticsearch/src/main/java/org/hibernate/search/elasticsearch/dialect/impl/ElasticsearchDialect.java

@@ -7,6 +7,7 @@
 package org.hibernate.search.elasticsearch.dialect.impl;
 
 import org.hibernate.search.elasticsearch.gson.impl.GsonProvider;
+import org.hibernate.search.elasticsearch.query.impl.ElasticsearchQueryFactory;
 import org.hibernate.search.elasticsearch.schema.impl.ElasticsearchSchemaAccessor;
 import org.hibernate.search.elasticsearch.schema.impl.ElasticsearchSchemaTranslator;
 import org.hibernate.search.elasticsearch.schema.impl.ElasticsearchSchemaValidator;
@@ -31,4 +32,6 @@ public interface ElasticsearchDialect {
 
 	MissingValueStrategy createMissingValueStrategy();
 
+	ElasticsearchQueryFactory createQueryFactory();
+
 }

elasticsearch/src/main/java/org/hibernate/search/elasticsearch/dialect/impl/es2/Elasticsearch2Dialect.java

@@ -10,6 +10,8 @@
 import org.hibernate.search.elasticsearch.gson.impl.DefaultGsonProvider;
 import org.hibernate.search.elasticsearch.gson.impl.GsonProvider;
 import org.hibernate.search.elasticsearch.nulls.impl.Elasticsearch2MissingValueStrategy;
+import org.hibernate.search.elasticsearch.query.impl.Elasticsearch2QueryFactory;
+import org.hibernate.search.elasticsearch.query.impl.ElasticsearchQueryFactory;
 import org.hibernate.search.elasticsearch.schema.impl.Elasticsearch2SchemaTranslator;
 import org.hibernate.search.elasticsearch.schema.impl.Elasticsearch2SchemaValidator;
 import org.hibernate.search.elasticsearch.schema.impl.ElasticsearchSchemaAccessor;
@@ -62,4 +64,9 @@ public MissingValueStrategy createMissingValueStrategy() {
 		return Elasticsearch2MissingValueStrategy.INSTANCE;
 	}
 
+	@Override
+	public ElasticsearchQueryFactory createQueryFactory() {
+		return new Elasticsearch2QueryFactory();
+	}
+
 }

elasticsearch/src/main/java/org/hibernate/search/elasticsearch/dialect/impl/es5/Elasticsearch5Dialect.java

@@ -10,6 +10,8 @@
 import org.hibernate.search.elasticsearch.gson.impl.DefaultGsonProvider;
 import org.hibernate.search.elasticsearch.gson.impl.GsonProvider;
 import org.hibernate.search.elasticsearch.nulls.impl.Elasticsearch5MissingValueStrategy;
+import org.hibernate.search.elasticsearch.query.impl.Elasticsearch5QueryFactory;
+import org.hibernate.search.elasticsearch.query.impl.ElasticsearchQueryFactory;
 import org.hibernate.search.elasticsearch.schema.impl.Elasticsearch5SchemaTranslator;
 import org.hibernate.search.elasticsearch.schema.impl.Elasticsearch5SchemaValidator;
 import org.hibernate.search.elasticsearch.schema.impl.ElasticsearchSchemaAccessor;
@@ -62,4 +64,9 @@ public MissingValueStrategy createMissingValueStrategy() {
 		return Elasticsearch5MissingValueStrategy.INSTANCE;
 	}
 
+	@Override
+	public ElasticsearchQueryFactory createQueryFactory() {
+		return new Elasticsearch5QueryFactory();
+	}
+
 }

elasticsearch/src/main/java/org/hibernate/search/elasticsearch/impl/DefaultElasticsearchService.java

@@ -17,6 +17,7 @@
 import org.hibernate.search.elasticsearch.dialect.impl.ElasticsearchDialectFactory;
 import org.hibernate.search.elasticsearch.gson.impl.GsonProvider;
 import org.hibernate.search.elasticsearch.processor.impl.ElasticsearchWorkProcessor;
+import org.hibernate.search.elasticsearch.query.impl.ElasticsearchQueryFactory;
 import org.hibernate.search.elasticsearch.schema.impl.DefaultElasticsearchSchemaCreator;
 import org.hibernate.search.elasticsearch.schema.impl.DefaultElasticsearchSchemaDropper;
 import org.hibernate.search.elasticsearch.schema.impl.DefaultElasticsearchSchemaMigrator;
@@ -52,8 +53,6 @@ public class DefaultElasticsearchService implements ElasticsearchService, Starta
 
 	private static final String QUERY_PROPERTIES_PREFIX = "hibernate.search.";
 
-	private ElasticsearchQueryOptions queryOptions;
-
 	private ElasticsearchClient client;
 
 	private GsonProvider gsonProvider;
@@ -74,6 +73,10 @@ public class DefaultElasticsearchService implements ElasticsearchService, Starta
 
 	private MissingValueStrategy missingValueStrategy;
 
+	private ElasticsearchQueryFactory queryFactory;
+
+	private ElasticsearchQueryOptions queryOptions;
+
 	@Override
 	public void start(Properties properties, BuildContext context) {
 		ServiceManager serviceManager = context.getServiceManager();
@@ -108,6 +111,8 @@ public void start(Properties properties, BuildContext context) {
 			this.schemaMigrator = new DefaultElasticsearchSchemaMigrator( schemaAccessor, schemaValidator );
 
 			this.missingValueStrategy = dialect.createMissingValueStrategy();
+
+			this.queryFactory = dialect.createQueryFactory();
 		}
 	}
 
@@ -172,6 +177,11 @@ public MissingValueStrategy getMissingValueStrategy() {
 		return missingValueStrategy;
 	}
 
+	@Override
+	public ElasticsearchQueryFactory getQueryFactory() {
+		return queryFactory;
+	}
+
 	@Override
 	public ElasticsearchQueryOptions getQueryOptions() {
 		return queryOptions;

elasticsearch/src/main/java/org/hibernate/search/elasticsearch/impl/ElasticsearchHSQueryImpl.java

@@ -657,15 +657,10 @@ private void addScriptFields(JsonBuilder.Object payloadBuilder) {
 				// the results. If we don't sort by distance, we need to request for the distance using a script_field.
 				payloadBuilder.add( "script_fields",
 						JsonBuilder.object().add( SPATIAL_DISTANCE_FIELD, JsonBuilder.object()
-							.add( "script", JsonBuilder.object()
-								.add( "params",
-										JsonBuilder.object()
-												.addProperty( "lat", spatialSearchCenter.getLatitude() )
-												.addProperty( "lon", spatialSearchCenter.getLongitude() )
-								)
-								// We multiply by 0.001 to Convert from meters to kilmeters
-								.addProperty( "inline", "doc['" + spatialFieldName + "'] ? doc['" + spatialFieldName + "'].arcDistance(lat,lon)*0.001 : null" )
-								.addProperty( "lang", "groovy" )
+							.add(
+									"script",
+									elasticsearchService.getQueryFactory()
+											.createSpatialDistanceScript( spatialSearchCenter, spatialFieldName )
 							)
 						)
 				);

elasticsearch/src/main/java/org/hibernate/search/elasticsearch/impl/ElasticsearchService.java

@@ -8,6 +8,7 @@
 
 import org.hibernate.search.elasticsearch.gson.impl.GsonProvider;
 import org.hibernate.search.elasticsearch.processor.impl.ElasticsearchWorkProcessor;
+import org.hibernate.search.elasticsearch.query.impl.ElasticsearchQueryFactory;
 import org.hibernate.search.elasticsearch.schema.impl.ElasticsearchSchemaCreator;
 import org.hibernate.search.elasticsearch.schema.impl.ElasticsearchSchemaDropper;
 import org.hibernate.search.elasticsearch.schema.impl.ElasticsearchSchemaMigrator;
@@ -41,6 +42,8 @@ public interface ElasticsearchService extends Service {
 
 	MissingValueStrategy getMissingValueStrategy();
 
+	ElasticsearchQueryFactory getQueryFactory();
+
 	ElasticsearchQueryOptions getQueryOptions();
 
 }

elasticsearch/src/main/java/org/hibernate/search/elasticsearch/query/impl/Elasticsearch2QueryFactory.java

@@ -0,0 +1,37 @@
+/*
+ * Hibernate Search, full-text search for your domain model
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+package org.hibernate.search.elasticsearch.query.impl;
+
+import org.hibernate.search.elasticsearch.impl.JsonBuilder;
+import org.hibernate.search.spatial.Coordinates;
+
+import com.google.gson.JsonObject;
+
+/**
+ * @author Yoann Rodiere
+ */
+public class Elasticsearch2QueryFactory implements ElasticsearchQueryFactory {
+
+	@Override
+	public JsonObject createSpatialDistanceScript(Coordinates center, String spatialFieldName) {
+		return JsonBuilder.object()
+				.add( "params",
+						JsonBuilder.object()
+								.addProperty( "lat", center.getLatitude() )
+								.addProperty( "lon", center.getLongitude() )
+				)
+				// We multiply by 0.001 to Convert from meters to kilometers
+				.addProperty(
+						"inline",
+						"doc['" + spatialFieldName + "'] ?"
+								+ " doc['" + spatialFieldName + "'].arcDistance(lat,lon)*0.001"
+								+ " : null" )
+				.addProperty( "lang", "groovy" )
+				.build();
+	}
+
+}

elasticsearch/src/main/java/org/hibernate/search/elasticsearch/query/impl/Elasticsearch5QueryFactory.java

@@ -0,0 +1,37 @@
+/*
+ * Hibernate Search, full-text search for your domain model
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+package org.hibernate.search.elasticsearch.query.impl;
+
+import org.hibernate.search.elasticsearch.impl.JsonBuilder;
+import org.hibernate.search.spatial.Coordinates;
+
+import com.google.gson.JsonObject;
+
+/**
+ * @author Yoann Rodiere
+ */
+public class Elasticsearch5QueryFactory implements ElasticsearchQueryFactory {
+
+	@Override
+	public JsonObject createSpatialDistanceScript(Coordinates center, String spatialFieldName) {
+		return JsonBuilder.object()
+				.add( "params",
+						JsonBuilder.object()
+								.addProperty( "lat", center.getLatitude() )
+								.addProperty( "lon", center.getLongitude() )
+				)
+				// We multiply by 0.001 to Convert from meters to kilometers
+				.addProperty(
+						"inline",
+						"doc['" + spatialFieldName + "'].value !== null ?"
+								+ " doc['" + spatialFieldName + "'].arcDistance(params.lat,params.lon)*0.001"
+								+ " : null" )
+				.addProperty( "lang", "painless" )
+				.build();
+	}
+
+}

elasticsearch/src/main/java/org/hibernate/search/elasticsearch/query/impl/ElasticsearchQueryFactory.java

@@ -0,0 +1,27 @@
+/*
+ * Hibernate Search, full-text search for your domain model
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+package org.hibernate.search.elasticsearch.query.impl;
+
+import org.hibernate.search.spatial.Coordinates;
+
+import com.google.gson.JsonObject;
+
+/**
+ * An object responsible for creating parts of an Elasticsearch JSON query.
+ * <p>
+ * Should eventually be responsible for building the whole JSON query,
+ * see HSEARCH-2750.
+ *
+ * @see <a href="https://hibernate.atlassian.net/browse/HSEARCH-2750">HSEARCH-2750</a>
+ *
+ * @author Yoann Rodiere
+ */
+public interface ElasticsearchQueryFactory {
+
+	JsonObject createSpatialDistanceScript(Coordinates center, String spatialFieldName);
+
+}

elasticsearch/src/test/resources/elasticsearch/5.0/configuration/elasticsearch.yml

@@ -64,7 +64,3 @@ discovery.zen.minimum_master_nodes: 1
 # Disable starting multiple nodes on a single system:
 #
 node.max_local_storage_nodes: 1
-#
-# Enable Groovy scripting support for search: useful for spatial queries
-#
-script.engine.groovy.inline.search: true

integrationtest/wildfly/src/test/resources/elasticsearch/5.0/configuration/elasticsearch.yml

@@ -64,7 +64,3 @@ discovery.zen.minimum_master_nodes: 1
 # Disable starting multiple nodes on a single system:
 #
 node.max_local_storage_nodes: 1
-#
-# Enable Groovy scripting support for search: useful for spatial queries
-#
-script.engine.groovy.inline.search: true