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* 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.ResultSet;
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.remote.traversal.RemoteTraversal;
import org.apache.tinkerpop.gremlin.process.traversal.Bytecode;
import org.apache.tinkerpop.gremlin.process.traversal.Traversal;
import org.apache.tinkerpop.gremlin.process.traversal.TraversalSource;
import org.apache.tinkerpop.gremlin.process.traversal.Traverser;
import org.apache.tinkerpop.gremlin.structure.Graph;
import org.apache.tinkerpop.gremlin.structure.util.GraphFactory;
import org.apache.tinkerpop.gremlin.util.iterator.IteratorUtils;
import java.util.Iterator;
import java.util.Optional;
import java.util.concurrent.CompletableFuture;
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_DRIVER_CLUSTERFILE = TraversalSource.GREMLIN_REMOTE + "driver.clusterFile";
public static final String GREMLIN_REMOTE_DRIVER_SOURCENAME = TraversalSource.GREMLIN_REMOTE + "driver.sourceName";
private static final String DEFAULT_TRAVERSAL_SOURCE = "g";
private final Client client;
private final boolean tryCloseCluster;
private final String remoteTraversalSourceName;
private transient Optional<Configuration> conf = Optional.empty();
private static final boolean attachElements = Boolean.valueOf(System.getProperty("is.testing", "false"));
public DriverRemoteConnection(final Configuration conf) {
final boolean hasClusterConf = IteratorUtils.anyMatch(conf.getKeys(), k -> k.startsWith("clusterConfiguration"));
if (conf.containsKey(GREMLIN_REMOTE_DRIVER_CLUSTERFILE) && hasClusterConf)
throw new IllegalStateException(String.format("A configuration should not contain both '%s' and 'clusterConfiguration'", GREMLIN_REMOTE_DRIVER_CLUSTERFILE));
remoteTraversalSourceName = conf.getString(GREMLIN_REMOTE_DRIVER_SOURCENAME, DEFAULT_TRAVERSAL_SOURCE);
try {
final Cluster cluster;
if (!conf.containsKey(GREMLIN_REMOTE_DRIVER_CLUSTERFILE) && !hasClusterConf)
cluster = Cluster.open();
else
cluster = conf.containsKey(GREMLIN_REMOTE_DRIVER_CLUSTERFILE) ?
Cluster.open(conf.getString(GREMLIN_REMOTE_DRIVER_CLUSTERFILE)) : Cluster.open(conf.subset("clusterConfiguration"));
client = cluster.connect(Client.Settings.build().create()).alias(remoteTraversalSourceName);
} catch (Exception ex) {
throw new IllegalStateException(ex);
}
tryCloseCluster = true;
this.conf = Optional.of(conf);
}
private DriverRemoteConnection(final Cluster cluster, final boolean tryCloseCluster, final String remoteTraversalSourceName) {
client = cluster.connect(Client.Settings.build().create()).alias(remoteTraversalSourceName);
this.remoteTraversalSourceName = remoteTraversalSourceName;
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) {
remoteTraversalSourceName = conf.getString(GREMLIN_REMOTE_DRIVER_SOURCENAME, DEFAULT_TRAVERSAL_SOURCE);
client = cluster.connect(Client.Settings.build().create()).alias(remoteTraversalSourceName);
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, DEFAULT_TRAVERSAL_SOURCE);
}
/**
* 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 remoteTraversalSourceName) {
return new DriverRemoteConnection(cluster, false, remoteTraversalSourceName);
}
/**
* 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, DEFAULT_TRAVERSAL_SOURCE);
}
/**
* 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 remoteTraversalSourceName) {
try {
return new DriverRemoteConnection(Cluster.open(clusterConfFile), true, remoteTraversalSourceName);
} 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 remoteTraversalSourceName} 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 remoteTraversalSourceName = conf.getString(DEFAULT_TRAVERSAL_SOURCE, DEFAULT_TRAVERSAL_SOURCE);
if (conf.containsKey("clusterConfigurationFile"))
return using(conf.getString("clusterConfigurationFile"), remoteTraversalSourceName);
else {
return using(Cluster.open(conf.subset("clusterConfiguration")), remoteTraversalSourceName);
}
}
/**
* @deprecated As of release 3.2.2, replaced by {@link #submitAsync(Bytecode)}.
*/
@Deprecated
@Override
public <E> Iterator<Traverser.Admin<E>> submit(final Traversal<?, E> t) throws RemoteConnectionException {
try {
if (attachElements && !t.asAdmin().getStrategies().getStrategy(VertexProgramStrategy.class).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 DriverRemoteTraversal.AttachingTraverserIterator<>(client.submit(t.asAdmin().getBytecode()).iterator(), graph);
} else {
return new DriverRemoteTraversal.TraverserIterator<>(client.submit(t.asAdmin().getBytecode()).iterator());
}
} catch (Exception ex) {
throw new RemoteConnectionException(ex);
}
}
/**
* @deprecated As of release 3.2.4, replaced by {@link #submitAsync(Bytecode)}.
*/
@Deprecated
@Override
public <E> RemoteTraversal<?,E> submit(final Bytecode bytecode) throws RemoteConnectionException {
try {
final ResultSet rs = client.submit(bytecode);
return new DriverRemoteTraversal<>(rs, client, attachElements, conf);
} catch (Exception ex) {
throw new RemoteConnectionException(ex);
}
}
@Override
public <E> CompletableFuture<RemoteTraversal<?, E>> submitAsync(final Bytecode bytecode) throws RemoteConnectionException {
try {
return client.submitAsync(bytecode).thenApply(rs -> new DriverRemoteTraversal<>(rs, client, attachElements, conf));
} 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=" + remoteTraversalSourceName + "]";
}
}