/*
* 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.twill.internal.container;
import com.google.common.base.Preconditions;
import com.google.common.base.Supplier;
import com.google.common.util.concurrent.AbstractExecutionThreadService;
import com.google.common.util.concurrent.Futures;
import com.google.common.util.concurrent.ListenableFuture;
import com.google.common.util.concurrent.Service;
import com.google.common.util.concurrent.SettableFuture;
import com.google.gson.Gson;
import com.google.gson.JsonElement;
import org.apache.twill.api.Command;
import org.apache.twill.api.RunId;
import org.apache.twill.api.TwillRunnable;
import org.apache.twill.api.TwillRunnableSpecification;
import org.apache.twill.common.Threads;
import org.apache.twill.filesystem.Location;
import org.apache.twill.internal.AbstractTwillService;
import org.apache.twill.internal.BasicTwillContext;
import org.apache.twill.internal.ContainerInfo;
import org.apache.twill.internal.ContainerLiveNodeData;
import org.apache.twill.internal.ZKServiceDecorator;
import org.apache.twill.internal.logging.Loggings;
import org.apache.twill.internal.state.Message;
import org.apache.twill.internal.state.MessageCallback;
import org.apache.twill.internal.utils.Instances;
import org.apache.twill.zookeeper.ZKClient;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
/**
* This class act as a yarn container and run a {@link org.apache.twill.api.TwillRunnable}.
*/
public final class TwillContainerService extends AbstractTwillService {
private static final Logger LOG = LoggerFactory.getLogger(TwillContainerService.class);
private final TwillRunnableSpecification specification;
private final ClassLoader classLoader;
private final BasicTwillContext context;
private final ZKServiceDecorator serviceDelegate;
private ExecutorService commandExecutor;
private TwillRunnable runnable;
public TwillContainerService(BasicTwillContext context, ContainerInfo containerInfo, ZKClient zkClient,
RunId runId, TwillRunnableSpecification specification, ClassLoader classLoader,
Location applicationLocation) {
super(applicationLocation);
this.specification = specification;
this.classLoader = classLoader;
this.serviceDelegate = new ZKServiceDecorator(zkClient, runId,
createLiveNodeSupplier(createLiveNodeData(containerInfo)),
new ServiceDelegate());
this.context = context;
}
private ListenableFuture<String> processMessage(final String messageId, final Message message) {
LOG.debug("Message received: {} {}.", messageId, message);
if (handleSecureStoreUpdate(message)) {
return Futures.immediateFuture(messageId);
}
final SettableFuture<String> result = SettableFuture.create();
Command command = message.getCommand();
if (message.getType() == Message.Type.SYSTEM
&& "instances".equals(command.getCommand()) && command.getOptions().containsKey("count")) {
context.setInstanceCount(Integer.parseInt(command.getOptions().get("count")));
}
commandExecutor.execute(new Runnable() {
@Override
public void run() {
try {
runnable.handleCommand(message.getCommand());
result.set(messageId);
} catch (Exception e) {
result.setException(e);
}
}
});
return result;
}
private ContainerLiveNodeData createLiveNodeData(ContainerInfo containerInfo) {
// if debugging is enabled, log the port and register it in service discovery.
String debugPort = System.getProperty("twill.debug.port");
if (debugPort != null) {
LOG.info("JVM is listening for debugger on port {}", debugPort);
}
return new ContainerLiveNodeData(containerInfo.getId(),
containerInfo.getHost().getCanonicalHostName(),
debugPort);
}
private Supplier<? extends JsonElement> createLiveNodeSupplier(final ContainerLiveNodeData data) {
return new Supplier<JsonElement>() {
@Override
public JsonElement get() {
return new Gson().toJsonTree(data);
}
};
}
@Override
protected Service getServiceDelegate() {
return serviceDelegate;
}
private final class ServiceDelegate extends AbstractExecutionThreadService implements MessageCallback {
@Override
protected void startUp() throws Exception {
commandExecutor = Executors.newSingleThreadExecutor(
Threads.createDaemonThreadFactory("runnable-command-executor"));
Class<?> runnableClass = classLoader.loadClass(specification.getClassName());
Preconditions.checkArgument(TwillRunnable.class.isAssignableFrom(runnableClass),
"Class %s is not instance of TwillRunnable.", specification.getClassName());
runnable = Instances.newInstance((Class<TwillRunnable>) runnableClass);
runnable.initialize(context);
}
@Override
protected void triggerShutdown() {
try {
runnable.stop();
} catch (Throwable t) {
LOG.error("Exception when stopping runnable.", t);
}
}
@Override
protected void shutDown() throws Exception {
commandExecutor.shutdownNow();
runnable.destroy();
Loggings.forceFlush();
}
@Override
protected void run() throws Exception {
runnable.run();
}
@Override
public ListenableFuture<String> onReceived(String messageId, Message message) {
if (state() == State.RUNNING) {
// Only process message if the service is still alive
return processMessage(messageId, message);
}
return Futures.immediateFuture(messageId);
}
}
}