Github user anujgandharv commented on a diff in the pull request: https://github.com/apache/jena/pull/227#discussion_r106641289 --- Diff: jena-text/src/main/java/org/apache/jena/query/text/TextIndexES.java --- @@ -0,0 +1,394 @@ +/** + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF 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.apache.jena.query.text; + +import org.apache.jena.graph.Node; +import org.apache.jena.graph.NodeFactory; +import org.apache.jena.sparql.util.NodeFactoryExtra; +import org.elasticsearch.action.admin.indices.exists.indices.IndicesExistsRequest; +import org.elasticsearch.action.admin.indices.exists.indices.IndicesExistsResponse; +import org.elasticsearch.action.get.GetResponse; +import org.elasticsearch.action.index.IndexRequest; +import org.elasticsearch.action.search.SearchResponse; +import org.elasticsearch.action.update.UpdateRequest; +import org.elasticsearch.action.update.UpdateResponse; +import org.elasticsearch.client.Client; +import org.elasticsearch.client.transport.TransportClient; +import org.elasticsearch.common.settings.Settings; +import org.elasticsearch.common.transport.InetSocketTransportAddress; +import org.elasticsearch.common.xcontent.XContentBuilder; +import org.elasticsearch.index.query.QueryBuilders; +import org.elasticsearch.script.Script; +import org.elasticsearch.search.SearchHit; +import org.elasticsearch.transport.client.PreBuiltTransportClient; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import java.net.InetAddress; +import java.util.*; + +import static org.elasticsearch.common.xcontent.XContentFactory.jsonBuilder; + +/** + * Elastic Search Implementation of {@link TextIndex} + * + */ +public class TextIndexES implements TextIndex { + + /** + * The definition of the Entity we are trying to Index + */ + private final EntityDefinition docDef ; + + /** + * Thread safe ElasticSearch Java Client to perform Index operations + */ + private static Client client; + + /** + * The name of the index. Defaults to 'test' + */ + private final String indexName; + + static final String CLUSTER_NAME_PARAM = "cluster.name"; + + static final String NUM_OF_SHARDS_PARAM = "number_of_shards"; + + static final String NUM_OF_REPLICAS_PARAM = "number_of_replicas"; + + /** + * Number of maximum results to return in case no limit is specified on the search operation + */ + static final Integer MAX_RESULTS = 10000; + + private boolean isMultilingual ; + + private static final Logger LOGGER = LoggerFactory.getLogger(TextIndexES.class) ; + + public TextIndexES(TextIndexConfig config, ESSettings esSettings) { + + this.indexName = esSettings.getIndexName(); + this.docDef = config.getEntDef(); + + this.isMultilingual = config.isMultilingualSupport(); + if (this.isMultilingual && config.getEntDef().getLangField() == null) { + //multilingual index cannot work without lang field + docDef.setLangField("lang"); + } + try { + if(client == null) { + + LOGGER.debug("Initializing the Elastic Search Java Client with settings: " + esSettings); + Settings settings = Settings.builder() + .put(CLUSTER_NAME_PARAM, esSettings.getClusterName()).build(); + List<InetSocketTransportAddress> addresses = new ArrayList<>(); + for(String host: esSettings.getHostToPortMapping().keySet()) { + InetSocketTransportAddress addr = new InetSocketTransportAddress(InetAddress.getByName(host), esSettings.getHostToPortMapping().get(host)); + addresses.add(addr); + } + + InetSocketTransportAddress socketAddresses[] = new InetSocketTransportAddress[addresses.size()]; + client = new PreBuiltTransportClient(settings).addTransportAddresses(addresses.toArray(socketAddresses)); + LOGGER.debug("Successfully initialized the client"); + } + + IndicesExistsResponse exists = client.admin().indices().exists(new IndicesExistsRequest(indexName)).get(); + if(!exists.isExists()) { + Settings indexSettings = Settings.builder() + .put(NUM_OF_SHARDS_PARAM, esSettings.getShards()) + .put(NUM_OF_REPLICAS_PARAM, esSettings.getReplicas()) + .build(); + LOGGER.debug("Index with name " + indexName + " does not exist yet. Creating one with settings: " + indexSettings.toString()); + client.admin().indices().prepareCreate(indexName).setSettings(indexSettings).get(); + } + }catch (Exception e) { + throw new TextIndexException("Exception occured while instantiating ElasticSearch Text Index", e); + } + } + + + /** + * Constructor used mainly for performing Integration tests + * @param config an instance of {@link TextIndexConfig} + * @param client an instance of {@link TransportClient}. The client should already have been initialized with an index + */ + public TextIndexES(TextIndexConfig config, Client client, String indexName) { + this.docDef = config.getEntDef(); + this.isMultilingual = true; + this.client = client; + this.indexName = indexName; + } + + /** + * We do not have any specific logic to perform before committing + */ + @Override + public void prepareCommit() { + //Do Nothing + + } + + /** + * Commit happens in the individual get/add/delete operations + */ + @Override + public void commit() { + // Do Nothing + } + + /** + * We do not do rollback + */ + @Override + public void rollback() { + //Do Nothing + + } + + /** + * We don't have resources that need to be closed explicitely + */ + @Override + public void close() { + // Do Nothing + + } + + /** + * Update an Entity. Since we are doing Upserts in add entity anyways, we simply call {@link #addEntity(Entity)} + * method that takes care of updating the Entity as well. + * @param entity the entity to update. + */ + @Override + public void updateEntity(Entity entity) { + //Since Add entity also updates the indexed document in case it already exists, + // we can simply call the addEntity from here. + addEntity(entity); + } + + + /** + * Add an Entity to the ElasticSearch Index. + * The entity will be added as a new document in ES, if it does not already exists. + * If the Entity exists, then the entity will simply be updated. + * The entity will never be replaced. + * @param entity the entity to add + */ + @Override + public void addEntity(Entity entity) { + LOGGER.debug("Adding/Updating the entity in ES"); + + //The field that has a not null value in the current Entity instance. + //Required, mainly for building a script for the update command. + String fieldToAdd = null; + String fieldValueToAdd = ""; + try { + XContentBuilder builder = jsonBuilder() + .startObject(); + + for(String field: docDef.fields()) { + if(entity.get(field) != null) { + if(entity.getLanguage() != null && !entity.getLanguage().isEmpty() && isMultilingual) { + fieldToAdd = field + "_" + entity.getLanguage(); + } else { + fieldToAdd = field; + } + + fieldValueToAdd = (String) entity.get(field); + builder = builder.field(fieldToAdd, Arrays.asList(fieldValueToAdd)); + break; + } else { + //We are making sure that the field is at-least added to the index. + //This will help us tremendously when we are appending the data later in an already indexed document. + builder = builder.field(field, Collections.emptyList()); + } + + } + + builder = builder.endObject(); + IndexRequest indexRequest = new IndexRequest(indexName, docDef.getEntityField(), entity.getId()) + .source(builder); + + String addUpdateScript = "if(ctx._source.<fieldName> == null || ctx._source.<fieldName>.empty) " + + "{ctx._source.<fieldName>=['<fieldValue>'] } else {ctx._source.<fieldName>.add('<fieldValue>')}"; + addUpdateScript = addUpdateScript.replaceAll("<fieldName>", fieldToAdd).replaceAll("<fieldValue>", fieldValueToAdd); + + UpdateRequest upReq = new UpdateRequest(indexName, docDef.getEntityField(), entity.getId()) + .script(new Script(addUpdateScript)) + .upsert(indexRequest); + + UpdateResponse response = client.update(upReq).get(); + + LOGGER.debug("Received the following Update response : " + response + " for the following entity: " + entity); + + } catch(Exception e) { + throw new TextIndexException("Unable to Index the Entity in ElasticSearch.", e); + } + } + + /** + * Delete an entity. + * Since we are storing different predicate values within the same indexed document, + * deleting the document using entity Id is sufficient to delete all the related contents for a given entity. + * @param entity entity to delete + */ + @Override + public void deleteEntity(Entity entity) { + + String fieldToRemove = null; + String valueToRemove = null; + for(String field : docDef.fields()) { + if(entity.get(field) != null) { + fieldToRemove = field; + valueToRemove = (String)entity.get(field); + break; + } + } + + String script = "if(ctx._source.<fieldToRemove> != null && (ctx._source.<fieldToRemove>.empty != true) " + + "&& (ctx._source.<fieldToRemove>.indexOf('<valueToRemove>') >= 0)) " + + "{ctx._source.<fieldToRemove>.remove(ctx._source.<fieldToRemove>.indexOf('<valueToRemove>'))}"; + script = script.replaceAll("<fieldToRemove>", fieldToRemove).replaceAll("<valueToRemove>", valueToRemove); + + UpdateRequest updateRequest = new UpdateRequest(indexName, docDef.getEntityField(), entity.getId()) + .script(new Script(script)); + + try { + client.update(updateRequest).get(); + }catch(Exception e) { + throw new TextIndexException("Unable to delete entity.", e); + } + + LOGGER.debug("deleting content related to entity: " + entity.getId()); + + } + + /** + * Get an Entity given the subject Id + * @param uri the subject Id of the entity + * @return a map of field name and field values; + */ + @Override + public Map<String, Node> get(String uri) { + + GetResponse response; + Map<String, Node> result = new HashMap<>(); + + if(uri != null) { + response = client.prepareGet(indexName, docDef.getEntityField(), uri).get(); + if(response != null && !response.isSourceEmpty()) { + String entityField = response.getId(); + Node entity = NodeFactory.createURI(entityField) ; + result.put(docDef.getEntityField(), entity); + Map<String, Object> source = response.getSource(); + for (String field: docDef.fields()) { + Object fieldResponse = source.get(field); + + if(fieldResponse == null) { + //We wont return it. + continue; + } + else if(fieldResponse instanceof List<?>) { + //We are storing the values of fields as a List always. + //If there are values stored in the list, then we return the first value, + // else we do not include the field in the returned Map of Field -> Node Mapping + List<?> responseList = (List<?>)fieldResponse; + if(responseList != null && responseList.size() > 0) { + String fieldValue = (String)responseList.get(0); + Node fieldNode = NodeFactoryExtra.createLiteralNode(fieldValue, null, null); + result.put(field, fieldNode); + } + } + } + } + } + + return result; + } + + @Override + public List<TextHit> query(Node property, String qs) { + + return query(property, qs, MAX_RESULTS); + } + + /** + * Query the ElasticSearch for the given Node, with the given query String and limit. + * @param property the node property to make a search for + * @param qs the query string + * @param limit limit on the number of records to return + * @return List of {@link TextHit}s containing the documents that have been found + */ + @Override + public List<TextHit> query(Node property, String qs, int limit) { + + qs = parse(qs); + LOGGER.debug("Querying ElasticSearch for QueryString: " + qs); + SearchResponse response = client.prepareSearch(indexName) + .setTypes(docDef.getEntityField()) + .setQuery(QueryBuilders.queryStringQuery(qs)) + .setFrom(0).setSize(limit) + .get(); + + List<TextHit> results = new ArrayList<>() ; + for (SearchHit hit : response.getHits()) { + + Node literal; + String field = (property != null) ? docDef.getField(property) : docDef.getPrimaryField(); + List<String> value = (List<String>)hit.getSource().get(field); + if(value != null) { + literal = NodeFactory.createLiteral(value.get(0)); --- End diff -- OK. I think that is a good suggestion. It also keeps things simple. I think I have a mechanism to return ONLY the matched values in ES (I know it theoretically though have to test it out) but that will potentially have performance impacts and therefore I would not like to have it by default. So for now, I will always return NULL values for literals instead of wrong values. Thanks again @Osma. I will make the needful changes
--- If your project is set up for it, you can reply to this email and have your reply appear on GitHub as well. If your project does not have this feature enabled and wishes so, or if the feature is enabled but not working, please contact infrastructure at infrastruct...@apache.org or file a JIRA ticket with INFRA. ---