| /** |
| * 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.rya.api.client.mongo; |
| |
| import static java.util.Objects.requireNonNull; |
| |
| import java.io.ByteArrayOutputStream; |
| import java.io.OutputStream; |
| import java.nio.charset.StandardCharsets; |
| import java.text.DecimalFormat; |
| |
| import org.apache.accumulo.core.client.AccumuloException; |
| import org.apache.accumulo.core.client.AccumuloSecurityException; |
| import org.apache.rya.api.client.ExecuteSparqlQuery; |
| import org.apache.rya.api.client.InstanceDoesNotExistException; |
| import org.apache.rya.api.client.InstanceExists; |
| import org.apache.rya.api.client.RyaClientException; |
| import org.apache.rya.api.persist.RyaDAOException; |
| import org.apache.rya.mongodb.MongoDBRdfConfiguration; |
| import org.apache.rya.rdftriplestore.inference.InferenceEngineException; |
| import org.apache.rya.sail.config.RyaSailFactory; |
| import org.openrdf.query.BindingSet; |
| import org.openrdf.query.MalformedQueryException; |
| import org.openrdf.query.QueryEvaluationException; |
| import org.openrdf.query.QueryLanguage; |
| import org.openrdf.query.TupleQuery; |
| import org.openrdf.query.TupleQueryResultHandlerException; |
| import org.openrdf.query.resultio.text.csv.SPARQLResultsCSVWriter; |
| import org.openrdf.repository.RepositoryException; |
| import org.openrdf.repository.sail.SailRepository; |
| import org.openrdf.repository.sail.SailRepositoryConnection; |
| import org.openrdf.sail.Sail; |
| import org.openrdf.sail.SailException; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import edu.umd.cs.findbugs.annotations.DefaultAnnotation; |
| import edu.umd.cs.findbugs.annotations.NonNull; |
| |
| /** |
| * Execute a sparql query on mongo Rya. |
| */ |
| @DefaultAnnotation(NonNull.class) |
| public class MongoExecuteSparqlQuery implements ExecuteSparqlQuery { |
| private static final Logger log = LoggerFactory.getLogger(MongoExecuteSparqlQuery.class); |
| |
| private final MongoConnectionDetails connectionDetails; |
| private final InstanceExists instanceExists; |
| |
| /** |
| * Constructs an instance of {@link MongoExecuteSparqlQuery}. |
| * |
| * @param connectionDetails - Details to connect to the server. (not null) |
| * @param instanceExists - The interactor used to check if a Rya instance exists. (not null) |
| */ |
| public MongoExecuteSparqlQuery( |
| final MongoConnectionDetails connectionDetails, |
| final MongoInstanceExists instanceExists) { |
| this.connectionDetails = requireNonNull(connectionDetails); |
| this.instanceExists = requireNonNull(instanceExists); |
| } |
| |
| @Override |
| public String executeSparqlQuery(final String ryaInstanceName, final String sparqlQuery) throws InstanceDoesNotExistException, RyaClientException { |
| requireNonNull(ryaInstanceName); |
| requireNonNull(sparqlQuery); |
| |
| // Ensure the Rya Instance exists. |
| if (!instanceExists.exists(ryaInstanceName)) { |
| throw new InstanceDoesNotExistException(String.format("There is no Rya instance named '%s'.", ryaInstanceName)); |
| } |
| |
| Sail sail = null; |
| SailRepositoryConnection sailRepoConn = null; |
| try { |
| // Get a Sail object that is connected to the Rya instance. |
| final MongoDBRdfConfiguration ryaConf = connectionDetails.build(ryaInstanceName); |
| sail = RyaSailFactory.getInstance(ryaConf); |
| |
| final SailRepository sailRepo = new SailRepository(sail); |
| sailRepoConn = sailRepo.getConnection(); |
| |
| // Execute the query. |
| final long start = System.currentTimeMillis(); |
| final TupleQuery tupleQuery = sailRepoConn.prepareTupleQuery(QueryLanguage.SPARQL, sparqlQuery); |
| final ByteArrayOutputStream baos = new ByteArrayOutputStream(); |
| final CountingSPARQLResultsCSVWriter handler = new CountingSPARQLResultsCSVWriter(baos); |
| tupleQuery.evaluate(handler); |
| final long end = System.currentTimeMillis(); |
| |
| // Format and return the result of the query. |
| final String queryResult = new String(baos.toByteArray(), StandardCharsets.UTF_8); |
| final String queryDuration = new DecimalFormat("0.0##").format((end - start) / 1000.0); |
| |
| return "Query Result:\n" + |
| queryResult + |
| "Retrieved " + handler.getCount() + " results in " + queryDuration + " seconds."; |
| |
| } catch (SailException | RyaDAOException | InferenceEngineException | AccumuloException | AccumuloSecurityException e) { |
| throw new RyaClientException("Could not create the Sail object used to query the RYA instance.", e); |
| } catch (final MalformedQueryException | QueryEvaluationException | TupleQueryResultHandlerException | RepositoryException e) { |
| throw new RyaClientException("Could not execute the SPARQL query.", e); |
| } finally { |
| // Close the resources that were opened. |
| if(sailRepoConn != null) { |
| try { |
| sailRepoConn.close(); |
| } catch (final RepositoryException e) { |
| log.error("Couldn't close the SailRepositoryConnection object.", e); |
| } |
| } |
| |
| if(sail != null) { |
| try { |
| sail.shutDown(); |
| } catch (final SailException e) { |
| log.error("Couldn't close the Sail object.", e); |
| } |
| } |
| } |
| } |
| |
| /** |
| * Subclasses {@link SPARQLResultsCSVWriter} to keep track of the total count of handled {@link BindingSet} objects. |
| */ |
| private static class CountingSPARQLResultsCSVWriter extends SPARQLResultsCSVWriter { |
| |
| private int count = 0; |
| |
| /** |
| * @param out - The OutputStream for results to be written to. |
| */ |
| public CountingSPARQLResultsCSVWriter(final OutputStream out) { |
| super(out); |
| } |
| |
| @Override |
| public void handleSolution(final BindingSet bindingSet) throws TupleQueryResultHandlerException { |
| super.handleSolution(bindingSet); |
| count++; |
| } |
| |
| /** |
| * |
| * @return The number of BindingSets that were handled by {@link #handleSolution(BindingSet)}. |
| */ |
| public int getCount() { |
| return count; |
| } |
| } |
| } |