| /* |
| * 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.streams.client.command; |
| |
| import static java.util.Objects.requireNonNull; |
| |
| import java.util.Optional; |
| import java.util.UUID; |
| import java.util.concurrent.TimeUnit; |
| import java.util.concurrent.atomic.AtomicBoolean; |
| |
| import org.apache.rya.streams.api.entity.QueryResultStream; |
| import org.apache.rya.streams.api.entity.StreamsQuery; |
| import org.apache.rya.streams.api.interactor.GetQueryResultStream; |
| import org.apache.rya.streams.api.queries.InMemoryQueryRepository; |
| import org.apache.rya.streams.api.queries.QueryChangeLog; |
| import org.apache.rya.streams.api.queries.QueryRepository; |
| import org.apache.rya.streams.client.RyaStreamsCommand; |
| import org.apache.rya.streams.kafka.KafkaTopics; |
| import org.apache.rya.streams.kafka.interactor.KafkaGetQueryResultStream; |
| import org.apache.rya.streams.kafka.queries.KafkaQueryChangeLogFactory; |
| import org.apache.rya.streams.kafka.serialization.VisibilityBindingSetDeserializer; |
| import org.apache.rya.streams.kafka.serialization.VisibilityStatementDeserializer; |
| import org.openrdf.query.MalformedQueryException; |
| import org.openrdf.query.algebra.Reduced; |
| import org.openrdf.query.algebra.TupleExpr; |
| import org.openrdf.query.parser.sparql.SPARQLParser; |
| |
| import com.beust.jcommander.JCommander; |
| import com.beust.jcommander.Parameter; |
| import com.beust.jcommander.ParameterException; |
| import com.google.common.base.Strings; |
| import com.google.common.util.concurrent.AbstractScheduledService.Scheduler; |
| |
| import edu.umd.cs.findbugs.annotations.DefaultAnnotation; |
| import edu.umd.cs.findbugs.annotations.NonNull; |
| |
| /** |
| * A command that streams the results of a query to the console. |
| */ |
| @DefaultAnnotation(NonNull.class) |
| public class StreamResultsCommand implements RyaStreamsCommand { |
| |
| /** |
| * Command line parameters that are used by this command to configure itself. |
| */ |
| private static final class StreamResultsParameters extends RyaStreamsCommand.KafkaParameters { |
| |
| @Parameter(names = {"--queryId", "-q"}, required = true, description = "The query whose results will be streamed to the console.") |
| private String queryId; |
| |
| @Override |
| public String toString() { |
| final StringBuilder parameters = new StringBuilder(); |
| parameters.append(super.toString()); |
| |
| if (!Strings.isNullOrEmpty(queryId)) { |
| parameters.append("\tQuery ID: " + queryId); |
| parameters.append("\n"); |
| } |
| |
| return parameters.toString(); |
| } |
| } |
| |
| @Override |
| public String getCommand() { |
| return "stream-results"; |
| } |
| |
| @Override |
| public String getDescription() { |
| return "Stream the results of a query to the console."; |
| } |
| |
| @Override |
| public String getUsage() { |
| final JCommander parser = new JCommander(new StreamResultsParameters()); |
| |
| final StringBuilder usage = new StringBuilder(); |
| parser.usage(usage); |
| return usage.toString(); |
| } |
| |
| @Override |
| public boolean validArguments(final String[] args) { |
| boolean valid = true; |
| try { |
| new JCommander(new StreamResultsParameters(), args); |
| } catch(final ParameterException e) { |
| valid = false; |
| } |
| return valid; |
| } |
| |
| @Override |
| public void execute(final String[] args) throws ArgumentsException, ExecutionException { |
| requireNonNull(args); |
| |
| // Parse the command line arguments. |
| final StreamResultsParameters params = new StreamResultsParameters(); |
| try { |
| new JCommander(params, args); |
| } catch(final ParameterException e) { |
| throw new ArgumentsException("Could not stream the query's results because of invalid command line parameters.", e); |
| } |
| |
| // Create the Kafka backed QueryChangeLog. |
| final String bootstrapServers = params.kafkaIP + ":" + params.kafkaPort; |
| final String topic = KafkaTopics.queryChangeLogTopic(params.ryaInstance); |
| final QueryChangeLog queryChangeLog = KafkaQueryChangeLogFactory.make(bootstrapServers, topic); |
| |
| // Parse the Query ID from the command line parameters. |
| final UUID queryId; |
| try { |
| queryId = UUID.fromString( params.queryId ); |
| } catch(final IllegalArgumentException e) { |
| throw new ArgumentsException("Invalid Query ID " + params.queryId); |
| } |
| |
| //The DeleteQuery command doesn't use the scheduled service feature. |
| final Scheduler scheduler = Scheduler.newFixedRateSchedule(0L, 5, TimeUnit.SECONDS); |
| final QueryRepository queryRepo = new InMemoryQueryRepository(queryChangeLog, scheduler); |
| // Fetch the SPARQL of the query whose results will be streamed. |
| final String sparql; |
| try { |
| final Optional<StreamsQuery> sQuery = queryRepo.get(queryId); |
| if(!sQuery.isPresent()) { |
| throw new ExecutionException("Could not read the results for query with ID " + queryId + |
| " because no such query exists."); |
| } |
| sparql = sQuery.get().getSparql(); |
| } catch (final Exception e) { |
| throw new ExecutionException("Problem encountered while closing the QueryRepository.", e); |
| } |
| |
| // This command executes until the application is killed, so create a kill boolean. |
| final AtomicBoolean finished = new AtomicBoolean(false); |
| Runtime.getRuntime().addShutdownHook(new Thread() { |
| @Override |
| public void run() { |
| finished.set(true); |
| } |
| }); |
| |
| // Build the interactor based on the type of result the query produces. |
| final GetQueryResultStream<?> getQueryResultStream; |
| try { |
| final TupleExpr tupleExpr = new SPARQLParser().parseQuery(sparql, null).getTupleExpr(); |
| if(tupleExpr instanceof Reduced) { |
| getQueryResultStream = new KafkaGetQueryResultStream<>(params.kafkaIP, params.kafkaPort, VisibilityStatementDeserializer.class); |
| } else { |
| getQueryResultStream = new KafkaGetQueryResultStream<>(params.kafkaIP, params.kafkaPort, VisibilityBindingSetDeserializer.class); |
| } |
| } catch (final MalformedQueryException e) { |
| throw new ExecutionException("Could not parse the SPARQL for the query: " + sparql, e); |
| } |
| |
| // Iterate through the results and print them to the console until the program or the stream ends. |
| try (final QueryResultStream<?> stream = getQueryResultStream.fromStart(params.ryaInstance, queryId)) { |
| while(!finished.get()) { |
| for(final Object result : stream.poll(1000)) { |
| System.out.println(result); |
| } |
| } |
| } catch (final Exception e) { |
| System.err.println("Error while reading the results from the stream."); |
| e.printStackTrace(); |
| System.exit(1); |
| } |
| } |
| } |