| /* |
| * 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.tinkerpop.gremlin.driver.remote; |
| |
| import org.apache.commons.configuration.Configuration; |
| import org.apache.tinkerpop.gremlin.driver.Client; |
| import org.apache.tinkerpop.gremlin.driver.Cluster; |
| import org.apache.tinkerpop.gremlin.driver.Result; |
| import org.apache.tinkerpop.gremlin.process.computer.traversal.strategy.decoration.VertexProgramStrategy; |
| import org.apache.tinkerpop.gremlin.process.remote.RemoteConnection; |
| import org.apache.tinkerpop.gremlin.process.remote.RemoteConnectionException; |
| import org.apache.tinkerpop.gremlin.process.remote.RemoteGraph; |
| import org.apache.tinkerpop.gremlin.process.traversal.Traversal; |
| import org.apache.tinkerpop.gremlin.process.traversal.Traverser; |
| import org.apache.tinkerpop.gremlin.structure.Element; |
| import org.apache.tinkerpop.gremlin.structure.Graph; |
| import org.apache.tinkerpop.gremlin.structure.Property; |
| import org.apache.tinkerpop.gremlin.structure.util.Attachable; |
| import org.apache.tinkerpop.gremlin.structure.util.GraphFactory; |
| |
| import java.util.Iterator; |
| import java.util.Optional; |
| import java.util.function.Supplier; |
| |
| /** |
| * A {@link RemoteConnection} implementation for Gremlin Server. Each {@code DriverServerConnection} is bound to one |
| * graph instance hosted in Gremlin Server. |
| * |
| * @author Stephen Mallette (http://stephen.genoprime.com) |
| */ |
| public class DriverRemoteConnection implements RemoteConnection { |
| |
| public static final String GREMLIN_REMOTE_GRAPH_DRIVER_CLUSTERFILE = "gremlin.remoteGraph.driver.clusterFile"; |
| public static final String GREMLIN_REMOTE_GRAPH_DRIVER_GRAPHNAME = "gremlin.remoteGraph.driver.graphName"; |
| private static final String DEFAULT_GRAPH = "graph"; |
| private static final boolean attachElements = Boolean.valueOf(System.getProperty("is.testing", "false")); |
| |
| private final Client client; |
| private final boolean tryCloseCluster; |
| private final String connectionGraphName; |
| private transient Optional<Configuration> conf = Optional.empty(); |
| |
| public DriverRemoteConnection(final Configuration conf) { |
| if (conf.containsKey(GREMLIN_REMOTE_GRAPH_DRIVER_CLUSTERFILE) && conf.containsKey("clusterConfiguration")) |
| throw new IllegalStateException(String.format("A configuration should not contain both '%s' and 'clusterConfiguration'", GREMLIN_REMOTE_GRAPH_DRIVER_CLUSTERFILE)); |
| |
| connectionGraphName = conf.getString(GREMLIN_REMOTE_GRAPH_DRIVER_GRAPHNAME, DEFAULT_GRAPH); |
| |
| try { |
| final Cluster cluster; |
| if (!conf.containsKey(GREMLIN_REMOTE_GRAPH_DRIVER_CLUSTERFILE) && !conf.containsKey("clusterConfiguration")) |
| cluster = Cluster.open(); |
| else |
| cluster = conf.containsKey(GREMLIN_REMOTE_GRAPH_DRIVER_CLUSTERFILE) ? |
| Cluster.open(conf.getString(GREMLIN_REMOTE_GRAPH_DRIVER_CLUSTERFILE)) : Cluster.open(conf.subset("clusterConfiguration")); |
| |
| client = cluster.connect(Client.Settings.build().unrollTraversers(false).create()).alias(connectionGraphName); |
| } catch (Exception ex) { |
| throw new IllegalStateException(ex); |
| } |
| |
| tryCloseCluster = true; |
| this.conf = Optional.of(conf); |
| } |
| |
| private DriverRemoteConnection(final Cluster cluster, final boolean tryCloseCluster, final String connectionGraphName) { |
| client = cluster.connect(Client.Settings.build().unrollTraversers(false).create()).alias(connectionGraphName); |
| this.connectionGraphName = connectionGraphName; |
| this.tryCloseCluster = tryCloseCluster; |
| } |
| |
| /** |
| * This constructor is largely just for unit testing purposes and should not typically be used externally. |
| */ |
| DriverRemoteConnection(final Cluster cluster, final Configuration conf) { |
| connectionGraphName = conf.getString(GREMLIN_REMOTE_GRAPH_DRIVER_GRAPHNAME, DEFAULT_GRAPH); |
| client = cluster.connect(Client.Settings.build().unrollTraversers(false).create()).alias(connectionGraphName); |
| tryCloseCluster = false; |
| this.conf = Optional.of(conf); |
| } |
| |
| /** |
| * Creates a {@link DriverRemoteConnection} from an existing {@link Cluster} instance. When {@link #close()} is |
| * called, the {@link Cluster} is left open for the caller to close. By default, this method will bind the |
| * {@link RemoteConnection} to a graph on the server named "graph". |
| */ |
| public static DriverRemoteConnection using(final Cluster cluster) { |
| return using(cluster, "graph"); |
| } |
| |
| /** |
| * Creates a {@link DriverRemoteConnection} from an existing {@link Cluster} instance. When {@link #close()} is |
| * called, the {@link Cluster} is left open for the caller to close. |
| */ |
| public static DriverRemoteConnection using(final Cluster cluster, final String connectionGraphName) { |
| return new DriverRemoteConnection(cluster, false, connectionGraphName); |
| } |
| |
| /** |
| * Creates a {@link DriverRemoteConnection} using a new {@link Cluster} instance created from the supplied |
| * configuration file. When {@link #close()} is called, this new {@link Cluster} is also closed. By default, |
| * this method will bind the {@link RemoteConnection} to a graph on the server named "graph". |
| */ |
| public static DriverRemoteConnection using(final String clusterConfFile) { |
| return using(clusterConfFile, "graph"); |
| } |
| |
| /** |
| * Creates a {@link DriverRemoteConnection} using a new {@link Cluster} instance created from the supplied |
| * configuration file. When {@link #close()} is called, this new {@link Cluster} is also closed. |
| */ |
| public static DriverRemoteConnection using(final String clusterConfFile, final String connectionGraphName) { |
| try { |
| return new DriverRemoteConnection(Cluster.open(clusterConfFile), true, connectionGraphName); |
| } catch (Exception ex) { |
| throw new IllegalStateException(ex); |
| } |
| } |
| |
| /** |
| * Creates a {@link DriverRemoteConnection} using an Apache {@code Configuration} object. This method of creation |
| * is typically used by {@link RemoteGraph} when being constructed via {@link GraphFactory}. The |
| * {@code Configuration} object should contain one of two required keys, either: {@code clusterConfigurationFile} |
| * or {@code clusterConfiguration}. The {@code clusterConfigurationFile} key is a pointer to a file location |
| * containing a configuration for a {@link Cluster}. The {@code clusterConfiguration} should contain the actual |
| * contents of a configuration that would be used by a {@link Cluster}. This {@code configuration} may also |
| * contain the optional, but likely necessary, {@code connectionGraphName} which tells the |
| * {@code DriverServerConnection} which graph on the server to bind to. |
| */ |
| public static DriverRemoteConnection using(final Configuration conf) { |
| if (conf.containsKey("clusterConfigurationFile") && conf.containsKey("clusterConfiguration")) |
| throw new IllegalStateException("A configuration should not contain both 'clusterConfigurationFile' and 'clusterConfiguration'"); |
| |
| if (!conf.containsKey("clusterConfigurationFile") && !conf.containsKey("clusterConfiguration")) |
| throw new IllegalStateException("A configuration must contain either 'clusterConfigurationFile' and 'clusterConfiguration'"); |
| |
| final String connectionGraphName = conf.getString("connectionGraphName", "graph"); |
| if (conf.containsKey("clusterConfigurationFile")) |
| return using(conf.getString("clusterConfigurationFile"), connectionGraphName); |
| else { |
| return using(Cluster.open(conf.subset("clusterConfiguration")), connectionGraphName); |
| } |
| } |
| |
| @Override |
| public <E> Iterator<Traverser.Admin<E>> submit(final Traversal<?, E> t) throws RemoteConnectionException { |
| try { |
| if (attachElements && !t.asAdmin().getStrategies().toList().stream().filter(s -> s instanceof VertexProgramStrategy).findAny().isPresent()) { |
| if (!conf.isPresent()) throw new IllegalStateException("Traverser can't be reattached for testing"); |
| final Graph graph = ((Supplier<Graph>) conf.get().getProperty("hidden.for.testing.only")).get(); |
| return new AttachingTraverserIterator<>(client.submit(t).iterator(), graph); |
| } else { |
| return new TraverserIterator<>(client.submit(t).iterator()); |
| } |
| } catch (Exception ex) { |
| throw new RemoteConnectionException(ex); |
| } |
| } |
| |
| @Override |
| public void close() throws Exception { |
| try { |
| client.close(); |
| } catch (Exception ex) { |
| throw new RemoteConnectionException(ex); |
| } finally { |
| if (tryCloseCluster) |
| client.getCluster().close(); |
| } |
| } |
| |
| @Override |
| public String toString() { |
| return "DriverServerConnection-" + client.getCluster() + " [graph=" + connectionGraphName + "]"; |
| } |
| |
| static class TraverserIterator<E> implements Iterator<Traverser.Admin<E>> { |
| |
| private Iterator<Result> inner; |
| |
| public TraverserIterator(final Iterator<Result> resultIterator) { |
| inner = resultIterator; |
| } |
| |
| @Override |
| public boolean hasNext() { |
| return inner.hasNext(); |
| } |
| |
| @Override |
| public Traverser.Admin<E> next() { |
| return (Traverser.Admin<E>) inner.next().getObject(); |
| } |
| } |
| |
| static class AttachingTraverserIterator<E> extends TraverserIterator<E> { |
| private final Graph graph; |
| |
| public AttachingTraverserIterator(final Iterator<Result> resultIterator, final Graph graph) { |
| super(resultIterator); |
| this.graph = graph; |
| } |
| |
| @Override |
| public Traverser.Admin<E> next() { |
| final Traverser.Admin<E> traverser = super.next(); |
| if (traverser.get() instanceof Attachable && !(traverser.get() instanceof Property)) |
| traverser.set((E) ((Attachable<Element>) traverser.get()).attach(Attachable.Method.get(graph))); |
| return traverser; |
| } |
| } |
| } |