开发基于YARN的应用程序需要开发客户端程序和AppMaster程序：
我们基于程序自带的例子来实现提交application 到YARN的ResourceManger。
Distributed Shell application：Client 步骤：
连接 ResourceManager；
通过ApplicationClientProtocol协议 与 ApplicationsManager交互提交AM，与此同时可以通过该协议过去集群的一些信息
* <p> For the actual job submission, the client first has to create an {@link ApplicationSubmissionContext}.
* The {@link ApplicationSubmissionContext} defines the application details such as {@link ApplicationId}
* and application name, the priority assigned to the application and the queue
* to which this application needs to be assigned. In addition to this, the {@link ApplicationSubmissionContext}
* also defines the {@link ContainerLaunchContext} which describes the <code>Container</code> with which
* the {@link ApplicationMaster} is launched. </p>
*
* <p> The {@link ContainerLaunchContext} in this scenario defines the resources to be allocated for the
* {@link ApplicationMaster}'s container, the local resources (jars, configuration files) to be made available
* and the environment to be set for the {@link ApplicationMaster} and the commands to be executed to run the
* {@link ApplicationMaster}. <p>
*
* <p> Using the {@link ApplicationSubmissionContext}, the client submits the application to the
* <code>ResourceManager</code> and then monitors the application by requesting the <code>ResourceManager</code>
* for an {@link ApplicationReport} at regular time intervals. In case of the application taking too long, the client
* kills the application by submitting a {@link KillApplicationRequest} to the <code>ResourceManager</code>. </p>
*/
@InterfaceAudience.Public @InterfaceStability.Unstable public class Client { private static final Log LOG = LogFactory.getLog(Client.class); // Configuration private Configuration conf; private YarnClient yarnClient; // Application master specific info to register a new Application with RM/ASM private String appName = ""; // App master priority private int amPriority = 0; // Queue for App master private String amQueue = ""; // Amt. of memory resource to request for to run the App Master private int amMemory = 10; // Application master jar file private String appMasterJar = ""; // Main class to invoke application master private final String appMasterMainClass; // Shell command to be executed private String shellCommand = ""; // Location of shell script private String shellScriptPath = ""; // Args to be passed to the shell command private String shellArgs = ""; // Env variables to be setup for the shell command private Map<String, String> shellEnv = new HashMap<String, String>(); // Shell Command Container priority private int shellCmdPriority = 0; // Amt of memory to request for container in which shell script will be executed private int containerMemory = 10; // No. of containers in which the shell script needs to be executed private int numContainers = 1; // log4j.properties file // if available, add to local resources and set into classpath private String log4jPropFile = ""; // Start time for client private final long clientStartTime = System.currentTimeMillis(); // Timeout threshold for client. Kill app after time interval expires. private long clientTimeout = 600000; // Debug flag boolean debugFlag = false; // Command line options private Options opts; /** * @param args Command line arguments */ public static void main(String[] args) { boolean result = false; try { Client client = new Client(); LOG.info("Initializing Client"); try { boolean doRun = client.init(args); if (!doRun) { System.exit(0); } } catch (IllegalArgumentException e) { System.err.println(e.getLocalizedMessage()); client.printUsage(); System.exit(-1); } result = client.run(); } catch (Throwable t) { LOG.fatal("Error running CLient", t); System.exit(1); } if (result) { LOG.info("Application completed successfully"); System.exit(0); } LOG.error("Application failed to complete successfully"); System.exit(2); } /** */ public Client(Configuration conf) throws Exception { this( "org.apache.hadoop.yarn.applications.distributedshell.ApplicationMaster", conf); } Client(String appMasterMainClass, Configuration conf) { this.conf = conf; this.appMasterMainClass = appMasterMainClass; yarnClient = YarnClient.createYarnClient(); yarnClient.init(conf); opts = new Options(); opts.addOption("appname", true, "Application Name. Default value - DistributedShell"); opts.addOption("priority", true, "Application Priority. Default 0"); opts.addOption("queue", true, "RM Queue in which this application is to be submitted"); opts.addOption("timeout", true, "Application timeout in milliseconds"); opts.addOption("master_memory", true, "Amount of memory in MB to be requested to run the application master"); opts.addOption("jar", true, "Jar file containing the application master"); opts.addOption("shell_command", true, "Shell command to be executed by the Application Master"); opts.addOption("shell_script", true, "Location of the shell script to be executed"); opts.addOption("shell_args", true, "Command line args for the shell script"); opts.addOption("shell_env", true, "Environment for shell script. Specified as env_key=env_val pairs"); opts.addOption("shell_cmd_priority", true, "Priority for the shell command containers"); opts.addOption("container_memory", true, "Amount of memory in MB to be requested to run the shell command"); opts.addOption("num_containers", true, "No. of containers on which the shell command needs to be executed"); opts.addOption("log_properties", true, "log4j.properties file"); opts.addOption("debug", false, "Dump out debug information"); opts.addOption("help", false, "Print usage"); } /** */ public Client() throws Exception { this(new YarnConfiguration()); } /** * Helper function to print out usage */ private void printUsage() { new HelpFormatter().printHelp("Client", opts); } /** * Parse command line options * @param args Parsed command line options * @return Whether the init was successful to run the client * @throws ParseException */ public boolean init(String[] args) throws ParseException { CommandLine cliParser = new GnuParser().parse(opts, args); if (args.length == 0) { throw new IllegalArgumentException("No args specified for client to initialize"); } if (cliParser.hasOption("help")) { printUsage(); return false; } if (cliParser.hasOption("debug")) { debugFlag = true; } appName = cliParser.getOptionValue("appname", "DistributedShell"); amPriority = Integer.parseInt(cliParser.getOptionValue("priority", "0")); amQueue = cliParser.getOptionValue("queue", "default"); amMemory = Integer.parseInt(cliParser.getOptionValue("master_memory", "10")); if (amMemory < 0) { throw new IllegalArgumentException("Invalid memory specified for application master, exiting." + " Specified memory=" + amMemory); } if (!cliParser.hasOption("jar")) { throw new IllegalArgumentException("No jar file specified for application master"); } appMasterJar = cliParser.getOptionValue("jar"); if (!cliParser.hasOption("shell_command")) { throw new IllegalArgumentException("No shell command specified to be executed by application master"); } shellCommand = cliParser.getOptionValue("shell_command"); if (cliParser.hasOption("shell_script")) { shellScriptPath = cliParser.getOptionValue("shell_script"); } if (cliParser.hasOption("shell_args")) { shellArgs = cliParser.getOptionValue("shell_args"); } if (cliParser.hasOption("shell_env")) { String envs[] = cliParser.getOptionValues("shell_env"); for (String env : envs) { env = env.trim(); int index = env.indexOf('='); if (index == -1) { shellEnv.put(env, ""); continue; } String key = env.substring(0, index); String val = ""; if (index < (env.length()-1)) { val = env.substring(index+1); } shellEnv.put(key, val); } } shellCmdPriority = Integer.parseInt(cliParser.getOptionValue("shell_cmd_priority", "0")); containerMemory = Integer.parseInt(cliParser.getOptionValue("container_memory", "10")); numContainers = Integer.parseInt(cliParser.getOptionValue("num_containers", "1")); if (containerMemory < 0 || numContainers < 1) { throw new IllegalArgumentException("Invalid no. of containers or container memory specified, exiting." + " Specified containerMemory=" + containerMemory + ", numContainer=" + numContainers); } clientTimeout = Integer.parseInt(cliParser.getOptionValue("timeout", "600000")); log4jPropFile = cliParser.getOptionValue("log_properties", ""); return true; } /** * Main run function for the client * @return true if application completed successfully * @throws IOException * @throws YarnException */ public boolean run() throws IOException, YarnException { LOG.info("Running Client"); yarnClient.start(); YarnClusterMetrics clusterMetrics = yarnClient.getYarnClusterMetrics(); LOG.info("Got Cluster metric info from ASM" + ", numNodeManagers=" + clusterMetrics.getNumNodeManagers()); List<NodeReport> clusterNodeReports = yarnClient.getNodeReports( NodeState.RUNNING); LOG.info("Got Cluster node info from ASM"); for (NodeReport node : clusterNodeReports) { LOG.info("Got node report from ASM for" + ", nodeId=" + node.getNodeId() + ", nodeAddress" + node.getHttpAddress() + ", nodeRackName" + node.getRackName() + ", nodeNumContainers" + node.getNumContainers()); } QueueInfo queueInfo = yarnClient.getQueueInfo(this.amQueue); LOG.info("Queue info" + ", queueName=" + queueInfo.getQueueName() + ", queueCurrentCapacity=" + queueInfo.getCurrentCapacity() + ", queueMaxCapacity=" + queueInfo.getMaximumCapacity() + ", queueApplicationCount=" + queueInfo.getApplications().size() + ", queueChildQueueCount=" + queueInfo.getChildQueues().size()); List<QueueUserACLInfo> listAclInfo = yarnClient.getQueueAclsInfo(); for (QueueUserACLInfo aclInfo : listAclInfo) { for (QueueACL userAcl : aclInfo.getUserAcls()) { LOG.info("User ACL Info for Queue" + ", queueName=" + aclInfo.getQueueName() + ", userAcl=" + userAcl.name()); } } // Get a new application id YarnClientApplication app = yarnClient.createApplication(); GetNewApplicationResponse appResponse = app.getNewApplicationResponse(); // TODO get min/max resource capabilities from RM and change memory ask if needed // If we do not have min/max, we may not be able to correctly request // the required resources from the RM for the app master // Memory ask has to be a multiple of min and less than max. // Dump out information about cluster capability as seen by the resource manager int maxMem = appResponse.getMaximumResourceCapability().getMemory(); LOG.info("Max mem capabililty of resources in this cluster " + maxMem); // A resource ask cannot exceed the max. if (amMemory > maxMem) { LOG.info("AM memory specified above max threshold of cluster. Using max value." + ", specified=" + amMemory + ", max=" + maxMem); amMemory = maxMem; } // set the application name ApplicationSubmissionContext appContext = app.getApplicationSubmissionContext(); ApplicationId appId = appContext.getApplicationId(); appContext.setApplicationName(appName); // Set up the container launch context for the application master ContainerLaunchContext amContainer = Records.newRecord(ContainerLaunchContext.class); // set local resources for the application master // local files or archives as needed // In this scenario, the jar file for the application master is part of the local resources Map<String, LocalResource> localResources = new HashMap<String, LocalResource>(); LOG.info("Copy App Master jar from local filesystem and add to local environment"); // Copy the application master jar to the filesystem // Create a local resource to point to the destination jar path FileSystem fs = FileSystem.get(conf); Path src = new Path(appMasterJar); String pathSuffix = appName + "/" + appId.getId() + "/AppMaster.jar"; Path dst = new Path(fs.getHomeDirectory(), pathSuffix); fs.copyFromLocalFile(false, true, src, dst); FileStatus destStatus = fs.getFileStatus(dst); LocalResource amJarRsrc = Records.newRecord(LocalResource.class); // Set the type of resource - file or archive // archives are untarred at destination // we don't need the jar file to be untarred for now amJarRsrc.setType(LocalResourceType.FILE); // Set visibility of the resource // Setting to most private option amJarRsrc.setVisibility(LocalResourceVisibility.APPLICATION); // Set the resource to be copied over amJarRsrc.setResource(ConverterUtils.getYarnUrlFromPath(dst)); // Set timestamp and length of file so that the framework // can do basic sanity checks for the local resource // after it has been copied over to ensure it is the same // resource the client intended to use with the application amJarRsrc.setTimestamp(destStatus.getModificationTime()); amJarRsrc.setSize(destStatus.getLen()); localResources.put("AppMaster.jar", amJarRsrc); // Set the log4j properties if needed if (!log4jPropFile.isEmpty()) { Path log4jSrc = new Path(log4jPropFile); Path log4jDst = new Path(fs.getHomeDirectory(), "log4j.props"); fs.copyFromLocalFile(false, true, log4jSrc, log4jDst); FileStatus log4jFileStatus = fs.getFileStatus(log4jDst); LocalResource log4jRsrc = Records.newRecord(LocalResource.class); log4jRsrc.setType(LocalResourceType.FILE); log4jRsrc.setVisibility(LocalResourceVisibility.APPLICATION); log4jRsrc.setResource(ConverterUtils.getYarnUrlFromURI(log4jDst.toUri())); log4jRsrc.setTimestamp(log4jFileStatus.getModificationTime()); log4jRsrc.setSize(log4jFileStatus.getLen()); localResources.put("log4j.properties", log4jRsrc); } // The shell script has to be made available on the final container(s) // where it will be executed. // To do this, we need to first copy into the filesystem that is visible // to the yarn framework. // We do not need to set this as a local resource for the application // master as the application master does not need it. String hdfsShellScriptLocation = ""; long hdfsShellScriptLen = 0; long hdfsShellScriptTimestamp = 0; if (!shellScriptPath.isEmpty()) { Path shellSrc = new Path(shellScriptPath); String shellPathSuffix = appName + "/" + appId.getId() + "/ExecShellScript.sh"; Path shellDst = new Path(fs.getHomeDirectory(), shellPathSuffix); fs.copyFromLocalFile(false, true, shellSrc, shellDst); hdfsShellScriptLocation = shellDst.toUri().toString(); FileStatus shellFileStatus = fs.getFileStatus(shellDst); hdfsShellScriptLen = shellFileStatus.getLen(); hdfsShellScriptTimestamp = shellFileStatus.getModificationTime(); } // Set local resource info into app master container launch context amContainer.setLocalResources(localResources); // Set the necessary security tokens as needed //amContainer.setContainerTokens(containerToken); // Set the env variables to be setup in the env where the application master will be run LOG.info("Set the environment for the application master"); Map<String, String> env = new HashMap<String, String>(); // put location of shell script into env // using the env info, the application master will create the correct local resource for the // eventual containers that will be launched to execute the shell scripts env.put(DSConstants.DISTRIBUTEDSHELLSCRIPTLOCATION, hdfsShellScriptLocation); env.put(DSConstants.DISTRIBUTEDSHELLSCRIPTTIMESTAMP, Long.toString(hdfsShellScriptTimestamp)); env.put(DSConstants.DISTRIBUTEDSHELLSCRIPTLEN, Long.toString(hdfsShellScriptLen)); // Add AppMaster.jar location to classpath // At some point we should not be required to add // the hadoop specific classpaths to the env. // It should be provided out of the box. // For now setting all required classpaths including // the classpath to "." for the application jar StringBuilder classPathEnv = new StringBuilder(Environment.CLASSPATH.$()) .append(File.pathSeparatorChar).append("./*"); for (String c : conf.getStrings( YarnConfiguration.YARN_APPLICATION_CLASSPATH, YarnConfiguration.DEFAULT_YARN_APPLICATION_CLASSPATH)) { classPathEnv.append(File.pathSeparatorChar); classPathEnv.append(c.trim()); } classPathEnv.append(File.pathSeparatorChar).append("./log4j.properties"); // add the runtime classpath needed for tests to work if (conf.getBoolean(YarnConfiguration.IS_MINI_YARN_CLUSTER, false)) { classPathEnv.append(':'); classPathEnv.append(System.getProperty("java.class.path")); } env.put("CLASSPATH", classPathEnv.toString()); amContainer.setEnvironment(env); // Set the necessary command to execute the application master Vector<CharSequence> vargs = new Vector<CharSequence>(30); // Set java executable command LOG.info("Setting up app master command"); vargs.add(Environment.JAVA_HOME.$() + "/bin/java"); // Set Xmx based on am memory size vargs.add("-Xmx" + amMemory + "m"); // Set class name vargs.add(appMasterMainClass); // Set params for Application Master vargs.add("--container_memory " + String.valueOf(containerMemory)); vargs.add("--num_containers " + String.valueOf(numContainers)); vargs.add("--priority " + String.valueOf(shellCmdPriority)); if (!shellCommand.isEmpty()) { vargs.add("--shell_command " + shellCommand + ""); } if (!shellArgs.isEmpty()) { vargs.add("--shell_args " + shellArgs + ""); } for (Map.Entry<String, String> entry : shellEnv.entrySet()) { vargs.add("--shell_env " + entry.getKey() + "=" + entry.getValue()); } if (debugFlag) { vargs.add("--debug"); } vargs.add("1>" + ApplicationConstants.LOG_DIR_EXPANSION_VAR + "/AppMaster.stdout"); vargs.add("2>" + ApplicationConstants.LOG_DIR_EXPANSION_VAR + "/AppMaster.stderr"); // Get final commmand StringBuilder command = new StringBuilder(); for (CharSequence str : vargs) { command.append(str).append(" "); } LOG.info("Completed setting up app master command " + command.toString()); List<String> commands = new ArrayList<String>(); commands.add(command.toString()); amContainer.setCommands(commands); // Set up resource type requirements // For now, only memory is supported so we set memory requirements Resource capability = Records.newRecord(Resource.class); capability.setMemory(amMemory); appContext.setResource(capability); // Service data is a binary blob that can be passed to the application // Not needed in this scenario // amContainer.setServiceData(serviceData); // Setup security tokens if (UserGroupInformation.isSecurityEnabled()) { Credentials credentials = new Credentials(); String tokenRenewer = conf.get(YarnConfiguration.RM_PRINCIPAL); if (tokenRenewer == null || tokenRenewer.length() == 0) { throw new IOException( "Can't get Master Kerberos principal for the RM to use as renewer"); } // For now, only getting tokens for the default file-system. final Token<?> tokens[] = fs.addDelegationTokens(tokenRenewer, credentials); if (tokens != null) { for (Token<?> token : tokens) { LOG.info("Got dt for " + fs.getUri() + "; " + token); } } DataOutputBuffer dob = new DataOutputBuffer(); credentials.writeTokenStorageToStream(dob); ByteBuffer fsTokens = ByteBuffer.wrap(dob.getData(), 0, dob.getLength()); amContainer.setTokens(fsTokens); } appContext.setAMContainerSpec(amContainer); // Set the priority for the application master Priority pri = Records.newRecord(Priority.class); // TODO - what is the range for priority? how to decide? pri.setPriority(amPriority); appContext.setPriority(pri); // Set the queue to which this application is to be submitted in the RM appContext.setQueue(amQueue); // Submit the application to the applications manager // SubmitApplicationResponse submitResp = applicationsManager.submitApplication(appRequest); // Ignore the response as either a valid response object is returned on success // or an exception thrown to denote some form of a failure LOG.info("Submitting application to ASM"); yarnClient.submitApplication(appContext); // TODO // Try submitting the same request again // app submission failure? // Monitor the application return monitorApplication(appId); } /** * Monitor the submitted application for completion. * Kill application if time expires. * @param appId Application Id of application to be monitored * @return true if application completed successfully * @throws YarnException * @throws IOException */ private boolean monitorApplication(ApplicationId appId) throws YarnException, IOException { while (true) { // Check app status every 1 second. try { Thread.sleep(1000); } catch (InterruptedException e) { LOG.debug("Thread sleep in monitoring loop interrupted"); } // Get application report for the appId we are interested in ApplicationReport report = yarnClient.getApplicationReport(appId); LOG.info("Got application report from ASM for" + ", appId=" + appId.getId() + ", clientToAMToken=" + report.getClientToAMToken() + ", appDiagnostics=" + report.getDiagnostics() + ", appMasterHost=" + report.getHost() + ", appQueue=" + report.getQueue() + ", appMasterRpcPort=" + report.getRpcPort() + ", appStartTime=" + report.getStartTime() + ", yarnAppState=" + report.getYarnApplicationState().toString() + ", distributedFinalState=" + report.getFinalApplicationStatus().toString() + ", appTrackingUrl=" + report.getTrackingUrl() + ", appUser=" + report.getUser()); YarnApplicationState state = report.getYarnApplicationState(); FinalApplicationStatus dsStatus = report.getFinalApplicationStatus(); if (YarnApplicationState.FINISHED == state) { if (FinalApplicationStatus.SUCCEEDED == dsStatus) { LOG.info("Application has completed successfully. Breaking monitoring loop"); return true; } else { LOG.info("Application did finished unsuccessfully." + " YarnState=" + state.toString() + ", DSFinalStatus=" + dsStatus.toString() + ". Breaking monitoring loop"); return false; } } else if (YarnApplicationState.KILLED == state || YarnApplicationState.FAILED == state) { LOG.info("Application did not finish." + " YarnState=" + state.toString() + ", DSFinalStatus=" + dsStatus.toString() + ". Breaking monitoring loop"); return false; } if (System.currentTimeMillis() > (clientStartTime + clientTimeout)) { LOG.info("Reached client specified timeout for application. Killing application"); forceKillApplication(appId); return false; } } } /** * Kill a submitted application by sending a call to the ASM * @param appId Application Id to be killed. * @throws YarnException * @throws IOException */ private void forceKillApplication(ApplicationId appId) throws YarnException, IOException { // TODO clarify whether multiple jobs with the same app id can be submitted and be running at // the same time. // If yes, can we kill a particular attempt only? // Response can be ignored as it is non-null on success or // throws an exception in case of failures yarnClient.killApplication(appId); } }
AM：
/** * 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.hadoop.yarn.applications.distributedshell; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.net.URI; import java.net.URISyntaxException; import java.nio.ByteBuffer; import java.util.ArrayList; import java.util.HashMap; import java.util.Iterator; import java.util.List; import java.util.Map; import java.util.Vector; import java.util.concurrent.ConcurrentHashMap; import java.util.concurrent.ConcurrentMap; import java.util.concurrent.atomic.AtomicInteger; import com.google.common.annotations.VisibleForTesting; import org.apache.commons.cli.CommandLine; import org.apache.commons.cli.GnuParser; import org.apache.commons.cli.HelpFormatter; import org.apache.commons.cli.Options; import org.apache.commons.cli.ParseException; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.hadoop.classification.InterfaceAudience; import org.apache.hadoop.classification.InterfaceStability; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.io.DataOutputBuffer; import org.apache.hadoop.net.NetUtils; import org.apache.hadoop.security.Credentials; import org.apache.hadoop.security.UserGroupInformation; import org.apache.hadoop.security.token.Token; import org.apache.hadoop.yarn.api.ApplicationConstants; import org.apache.hadoop.yarn.api.ApplicationConstants.Environment; import org.apache.hadoop.yarn.api.ApplicationMasterProtocol; import org.apache.hadoop.yarn.api.ContainerManagementProtocol; import org.apache.hadoop.yarn.api.protocolrecords.AllocateRequest; import org.apache.hadoop.yarn.api.protocolrecords.AllocateResponse; import org.apache.hadoop.yarn.api.protocolrecords.FinishApplicationMasterRequest; import org.apache.hadoop.yarn.api.protocolrecords.RegisterApplicationMasterResponse; import org.apache.hadoop.yarn.api.protocolrecords.StartContainerRequest; import org.apache.hadoop.yarn.api.records.ApplicationAttemptId; import org.apache.hadoop.yarn.api.records.Container; import org.apache.hadoop.yarn.api.records.ContainerExitStatus; import org.apache.hadoop.yarn.api.records.ContainerId; import org.apache.hadoop.yarn.api.records.ContainerLaunchContext; import org.apache.hadoop.yarn.api.records.ContainerState; import org.apache.hadoop.yarn.api.records.ContainerStatus; import org.apache.hadoop.yarn.api.records.FinalApplicationStatus; import org.apache.hadoop.yarn.api.records.LocalResource; import org.apache.hadoop.yarn.api.records.LocalResourceType; import org.apache.hadoop.yarn.api.records.LocalResourceVisibility; import org.apache.hadoop.yarn.api.records.NodeReport; import org.apache.hadoop.yarn.api.records.Priority; import org.apache.hadoop.yarn.api.records.Resource; import org.apache.hadoop.yarn.api.records.ResourceRequest; import org.apache.hadoop.yarn.client.api.AMRMClient.ContainerRequest; import org.apache.hadoop.yarn.client.api.async.AMRMClientAsync; import org.apache.hadoop.yarn.client.api.async.NMClientAsync; import org.apache.hadoop.yarn.client.api.async.impl.NMClientAsyncImpl; import org.apache.hadoop.yarn.conf.YarnConfiguration; import org.apache.hadoop.yarn.exceptions.YarnException; import org.apache.hadoop.yarn.security.AMRMTokenIdentifier; import org.apache.hadoop.yarn.util.ConverterUtils; import org.apache.hadoop.yarn.util.Records; /** * An ApplicationMaster for executing shell commands on a set of launched * containers using the YARN framework. * * <p> * This class is meant to act as an example on how to write yarn-based * application masters. * </p> * * <p> * The ApplicationMaster is started on a container by the * <code>ResourceManager</code>'s launcher. The first thing that the * <code>ApplicationMaster</code> needs to do is to connect and register itself * with the <code>ResourceManager</code>. The registration sets up information * within the <code>ResourceManager</code> regarding what host:port the * ApplicationMaster is listening on to provide any form of functionality to a * client as well as a tracking url that a client can use to keep track of * status/job history if needed. However, in the distributedshell, trackingurl * and appMasterHost:appMasterRpcPort are not supported. * </p> * * <p> * The <code>ApplicationMaster</code> needs to send a heartbeat to the * <code>ResourceManager</code> at regular intervals to inform the * <code>ResourceManager</code> that it is up and alive. The * {@link ApplicationMasterProtocol#allocate} to the <code>ResourceManager</code> from the * <code>ApplicationMaster</code> acts as a heartbeat. * * <p> * For the actual handling of the job, the <code>ApplicationMaster</code> has to * request the <code>ResourceManager</code> via {@link AllocateRequest} for the * required no. of containers using {@link ResourceRequest} with the necessary * resource specifications such as node location, computational * (memory/disk/cpu) resource requirements. The <code>ResourceManager</code> * responds with an {@link AllocateResponse} that informs the * <code>ApplicationMaster</code> of the set of newly allocated containers, * completed containers as well as current state of available resources. * </p> * * <p> * For each allocated container, the <code>ApplicationMaster</code> can then set * up the necessary launch context via {@link ContainerLaunchContext} to specify * the allocated container id, local resources required by the executable, the * environment to be setup for the executable, commands to execute, etc. and * submit a {@link StartContainerRequest} to the {@link ContainerManagementProtocol} to * launch and execute the defined commands on the given allocated container. * </p> * * <p> * The <code>ApplicationMaster</code> can monitor the launched container by * either querying the <code>ResourceManager</code> using * {@link ApplicationMasterProtocol#allocate} to get updates on completed containers or via * the {@link ContainerManagementProtocol} by querying for the status of the allocated * container's {@link ContainerId}. * * <p> * After the job has been completed, the <code>ApplicationMaster</code> has to * send a {@link FinishApplicationMasterRequest} to the * <code>ResourceManager</code> to inform it that the * <code>ApplicationMaster</code> has been completed. */ @InterfaceAudience.Public @InterfaceStability.Unstable public class ApplicationMaster { private static final Log LOG = LogFactory.getLog(ApplicationMaster.class); // Configuration private Configuration conf; // Handle to communicate with the Resource Manager @SuppressWarnings("rawtypes") private AMRMClientAsync amRMClient; // Handle to communicate with the Node Manager private NMClientAsync nmClientAsync; // Listen to process the response from the Node Manager private NMCallbackHandler containerListener; // Application Attempt Id ( combination of attemptId and fail count ) private ApplicationAttemptId appAttemptID; // TODO // For status update for clients - yet to be implemented // Hostname of the container private String appMasterHostname = ""; // Port on which the app master listens for status updates from clients private int appMasterRpcPort = -1; // Tracking url to which app master publishes info for clients to monitor private String appMasterTrackingUrl = ""; // App Master configuration // No. of containers to run shell command on private int numTotalContainers = 1; // Memory to request for the container on which the shell command will run private int containerMemory = 10; // Priority of the request private int requestPriority; // Counter for completed containers ( complete denotes successful or failed ) private AtomicInteger numCompletedContainers = new AtomicInteger(); // Allocated container count so that we know how many containers has the RM // allocated to us private AtomicInteger numAllocatedContainers = new AtomicInteger(); // Count of failed containers private AtomicInteger numFailedContainers = new AtomicInteger(); // Count of containers already requested from the RM // Needed as once requested, we should not request for containers again. // Only request for more if the original requirement changes. private AtomicInteger numRequestedContainers = new AtomicInteger(); // Shell command to be executed private String shellCommand = ""; // Args to be passed to the shell command private String shellArgs = ""; // Env variables to be setup for the shell command private Map<String, String> shellEnv = new HashMap<String, String>(); // Location of shell script ( obtained from info set in env ) // Shell script path in fs private String shellScriptPath = ""; // Timestamp needed for creating a local resource private long shellScriptPathTimestamp = 0; // File length needed for local resource private long shellScriptPathLen = 0; // Hardcoded path to shell script in launch container's local env private final String ExecShellStringPath = "ExecShellScript.sh"; private volatile boolean done; private volatile boolean success; private ByteBuffer allTokens; // Launch threads private List<Thread> launchThreads = new ArrayList<Thread>(); /** * @param args Command line args */ public static void main(String[] args) { boolean result = false; try { ApplicationMaster appMaster = new ApplicationMaster(); LOG.info("Initializing ApplicationMaster"); boolean doRun = appMaster.init(args); if (!doRun) { System.exit(0); } result = appMaster.run(); } catch (Throwable t) { LOG.fatal("Error running ApplicationMaster", t); System.exit(1); } if (result) { LOG.info("Application Master completed successfully. exiting"); System.exit(0); } else { LOG.info("Application Master failed. exiting"); System.exit(2); } } /** * Dump out contents of $CWD and the environment to stdout for debugging */ private void dumpOutDebugInfo() { LOG.info("Dump debug output"); Map<String, String> envs = System.getenv(); for (Map.Entry<String, String> env : envs.entrySet()) { LOG.info("System env: key=" + env.getKey() + ", val=" + env.getValue()); System.out.println("System env: key=" + env.getKey() + ", val=" + env.getValue()); } String cmd = "ls -al"; Runtime run = Runtime.getRuntime(); Process pr = null; try { pr = run.exec(cmd); pr.waitFor(); BufferedReader buf = new BufferedReader(new InputStreamReader( pr.getInputStream())); String line = ""; while ((line = buf.readLine()) != null) { LOG.info("System CWD content: " + line); System.out.println("System CWD content: " + line); } buf.close(); } catch (IOException e) { e.printStackTrace(); } catch (InterruptedException e) { e.printStackTrace(); } } public ApplicationMaster() { // Set up the configuration conf = new YarnConfiguration(); } /** * Parse command line options * * @param args Command line args * @return Whether init successful and run should be invoked * @throws ParseException * @throws IOException */ public boolean init(String[] args) throws ParseException, IOException { Options opts = new Options(); opts.addOption("app_attempt_id", true, "App Attempt ID. Not to be used unless for testing purposes"); opts.addOption("shell_command", true, "Shell command to be executed by the Application Master"); opts.addOption("shell_script", true, "Location of the shell script to be executed"); opts.addOption("shell_args", true, "Command line args for the shell script"); opts.addOption("shell_env", true, "Environment for shell script. Specified as env_key=env_val pairs"); opts.addOption("container_memory", true, "Amount of memory in MB to be requested to run the shell command"); opts.addOption("num_containers", true, "No. of containers on which the shell command needs to be executed"); opts.addOption("priority", true, "Application Priority. Default 0"); opts.addOption("debug", false, "Dump out debug information"); opts.addOption("help", false, "Print usage"); CommandLine cliParser = new GnuParser().parse(opts, args); if (args.length == 0) { printUsage(opts); throw new IllegalArgumentException( "No args specified for application master to initialize"); } if (cliParser.hasOption("help")) { printUsage(opts); return false; } if (cliParser.hasOption("debug")) { dumpOutDebugInfo(); } Map<String, String> envs = System.getenv(); if (!envs.containsKey(Environment.CONTAINER_ID.name())) { if (cliParser.hasOption("app_attempt_id")) { String appIdStr = cliParser.getOptionValue("app_attempt_id", ""); appAttemptID = ConverterUtils.toApplicationAttemptId(appIdStr); } else { throw new IllegalArgumentException( "Application Attempt Id not set in the environment"); } } else { ContainerId containerId = ConverterUtils.toContainerId(envs .get(Environment.CONTAINER_ID.name())); appAttemptID = containerId.getApplicationAttemptId(); } if (!envs.containsKey(ApplicationConstants.APP_SUBMIT_TIME_ENV)) { throw new RuntimeException(ApplicationConstants.APP_SUBMIT_TIME_ENV + " not set in the environment"); } if (!envs.containsKey(Environment.NM_HOST.name())) { throw new RuntimeException(Environment.NM_HOST.name() + " not set in the environment"); } if (!envs.containsKey(Environment.NM_HTTP_PORT.name())) { throw new RuntimeException(Environment.NM_HTTP_PORT + " not set in the environment"); } if (!envs.containsKey(Environment.NM_PORT.name())) { throw new RuntimeException(Environment.NM_PORT.name() + " not set in the environment"); } LOG.info("Application master for app" + ", appId=" + appAttemptID.getApplicationId().getId() + ", clustertimestamp=" + appAttemptID.getApplicationId().getClusterTimestamp() + ", attemptId=" + appAttemptID.getAttemptId()); if (!cliParser.hasOption("shell_command")) { throw new IllegalArgumentException( "No shell command specified to be executed by application master"); } shellCommand = cliParser.getOptionValue("shell_command"); if (cliParser.hasOption("shell_args")) { shellArgs = cliParser.getOptionValue("shell_args"); } if (cliParser.hasOption("shell_env")) { String shellEnvs[] = cliParser.getOptionValues("shell_env"); for (String env : shellEnvs) { env = env.trim(); int index = env.indexOf('='); if (index == -1) { shellEnv.put(env, ""); continue; } String key = env.substring(0, index); String val = ""; if (index < (env.length() - 1)) { val = env.substring(index + 1); } shellEnv.put(key, val); } } if (envs.containsKey(DSConstants.DISTRIBUTEDSHELLSCRIPTLOCATION)) { shellScriptPath = envs.get(DSConstants.DISTRIBUTEDSHELLSCRIPTLOCATION); if (envs.containsKey(DSConstants.DISTRIBUTEDSHELLSCRIPTTIMESTAMP)) { shellScriptPathTimestamp = Long.valueOf(envs .get(DSConstants.DISTRIBUTEDSHELLSCRIPTTIMESTAMP)); } if (envs.containsKey(DSConstants.DISTRIBUTEDSHELLSCRIPTLEN)) { shellScriptPathLen = Long.valueOf(envs .get(DSConstants.DISTRIBUTEDSHELLSCRIPTLEN)); } if (!shellScriptPath.isEmpty() && (shellScriptPathTimestamp <= 0 || shellScriptPathLen <= 0)) { LOG.error("Illegal values in env for shell script path" + ", path=" + shellScriptPath + ", len=" + shellScriptPathLen + ", timestamp=" + shellScriptPathTimestamp); throw new IllegalArgumentException( "Illegal values in env for shell script path"); } } containerMemory = Integer.parseInt(cliParser.getOptionValue( "container_memory", "10")); numTotalContainers = Integer.parseInt(cliParser.getOptionValue( "num_containers", "1")); if (numTotalContainers == 0) { throw new IllegalArgumentException( "Cannot run distributed shell with no containers"); } requestPriority = Integer.parseInt(cliParser .getOptionValue("priority", "0")); return true; } /** * Helper function to print usage * * @param opts Parsed command line options */ private void printUsage(Options opts) { new HelpFormatter().printHelp("ApplicationMaster", opts); } /** * Main run function for the application master * * @throws YarnException * @throws IOException */ @SuppressWarnings({ "unchecked" }) public boolean run() throws YarnException, IOException { LOG.info("Starting ApplicationMaster"); Credentials credentials = UserGroupInformation.getCurrentUser().getCredentials(); DataOutputBuffer dob = new DataOutputBuffer(); credentials.writeTokenStorageToStream(dob); // Now remove the AM->RM token so that containers cannot access it. Iterator<Token<?>> iter = credentials.getAllTokens().iterator(); while (iter.hasNext()) { Token<?> token = iter.next(); if (token.getKind().equals(AMRMTokenIdentifier.KIND_NAME)) { iter.remove(); } } allTokens = ByteBuffer.wrap(dob.getData(), 0, dob.getLength()); AMRMClientAsync.CallbackHandler allocListener = new RMCallbackHandler(); amRMClient = AMRMClientAsync.createAMRMClientAsync(1000, allocListener); amRMClient.init(conf); amRMClient.start(); containerListener = createNMCallbackHandler(); nmClientAsync = new NMClientAsyncImpl(containerListener); nmClientAsync.init(conf); nmClientAsync.start(); // Setup local RPC Server to accept status requests directly from clients // TODO need to setup a protocol for client to be able to communicate to // the RPC server // TODO use the rpc port info to register with the RM for the client to // send requests to this app master // Register self with ResourceManager // This will start heartbeating to the RM appMasterHostname = NetUtils.getHostname(); RegisterApplicationMasterResponse response = amRMClient .registerApplicationMaster(appMasterHostname, appMasterRpcPort, appMasterTrackingUrl); // Dump out information about cluster capability as seen by the // resource manager int maxMem = response.getMaximumResourceCapability().getMemory(); LOG.info("Max mem capabililty of resources in this cluster " + maxMem); // A resource ask cannot exceed the max. if (containerMemory > maxMem) { LOG.info("Container memory specified above max threshold of cluster." + " Using max value." + ", specified=" + containerMemory + ", max=" + maxMem); containerMemory = maxMem; } // Setup ask for containers from RM // Send request for containers to RM // Until we get our fully allocated quota, we keep on polling RM for // containers // Keep looping until all the containers are launched and shell script // executed on them ( regardless of success/failure). for (int i = 0; i < numTotalContainers; ++i) { ContainerRequest containerAsk = setupContainerAskForRM(); amRMClient.addContainerRequest(containerAsk); } numRequestedContainers.set(numTotalContainers); while (!done && (numCompletedContainers.get() != numTotalContainers)) { try { Thread.sleep(200); } catch (InterruptedException ex) {} } finish(); return success; } @VisibleForTesting NMCallbackHandler createNMCallbackHandler() { return new NMCallbackHandler(this); } private void finish() { // Join all launched threads // needed for when we time out // and we need to release containers for (Thread launchThread : launchThreads) { try { launchThread.join(10000); } catch (InterruptedException e) { LOG.info("Exception thrown in thread join: " + e.getMessage()); e.printStackTrace(); } } // When the application completes, it should stop all running containers LOG.info("Application completed. Stopping running containers"); nmClientAsync.stop(); // When the application completes, it should send a finish application // signal to the RM LOG.info("Application completed. Signalling finish to RM"); FinalApplicationStatus appStatus; String appMessage = null; success = true; if (numFailedContainers.get() == 0 && numCompletedContainers.get() == numTotalContainers) { appStatus = FinalApplicationStatus.SUCCEEDED; } else { appStatus = FinalApplicationStatus.FAILED; appMessage = "Diagnostics." + ", total=" + numTotalContainers + ", completed=" + numCompletedContainers.get() + ", allocated=" + numAllocatedContainers.get() + ", failed=" + numFailedContainers.get(); success = false; } try { amRMClient.unregisterApplicationMaster(appStatus, appMessage, null); } catch (YarnException ex) { LOG.error("Failed to unregister application", ex); } catch (IOException e) { LOG.error("Failed to unregister application", e); } amRMClient.stop(); } private class RMCallbackHandler implements AMRMClientAsync.CallbackHandler { @SuppressWarnings("unchecked") @Override public void onContainersCompleted(List<ContainerStatus> completedContainers) { LOG.info("Got response from RM for container ask, completedCnt=" + completedContainers.size()); for (ContainerStatus containerStatus : completedContainers) { LOG.info("Got container status for containerID=" + containerStatus.getContainerId() + ", state=" + containerStatus.getState() + ", exitStatus=" + containerStatus.getExitStatus() + ", diagnostics=" + containerStatus.getDiagnostics()); // non complete containers should not be here assert (containerStatus.getState() == ContainerState.COMPLETE); // increment counters for completed/failed containers int exitStatus = containerStatus.getExitStatus(); if (0 != exitStatus) { // container failed if (ContainerExitStatus.ABORTED != exitStatus) { // shell script failed // counts as completed numCompletedContainers.incrementAndGet(); numFailedContainers.incrementAndGet(); } else { // container was killed by framework, possibly preempted // we should re-try as the container was lost for some reason numAllocatedContainers.decrementAndGet(); numRequestedContainers.decrementAndGet(); // we do not need to release the container as it would be done // by the RM } } else { // nothing to do // container completed successfully numCompletedContainers.incrementAndGet(); LOG.info("Container completed successfully." + ", containerId=" + containerStatus.getContainerId()); } } // ask for more containers if any failed int askCount = numTotalContainers - numRequestedContainers.get(); numRequestedContainers.addAndGet(askCount); if (askCount > 0) { for (int i = 0; i < askCount; ++i) { ContainerRequest containerAsk = setupContainerAskForRM(); amRMClient.addContainerRequest(containerAsk); } } if (numCompletedContainers.get() == numTotalContainers) { done = true; } } @Override public void onContainersAllocated(List<Container> allocatedContainers) { LOG.info("Got response from RM for container ask, allocatedCnt=" + allocatedContainers.size()); numAllocatedContainers.addAndGet(allocatedContainers.size()); for (Container allocatedContainer : allocatedContainers) { LOG.info("Launching shell command on a new container." + ", containerId=" + allocatedContainer.getId() + ", containerNode=" + allocatedContainer.getNodeId().getHost() + ":" + allocatedContainer.getNodeId().getPort() + ", containerNodeURI=" + allocatedContainer.getNodeHttpAddress() + ", containerResourceMemory" + allocatedContainer.getResource().getMemory()); // + ", containerToken" // +allocatedContainer.getContainerToken().getIdentifier().toString()); LaunchContainerRunnable runnableLaunchContainer = new LaunchContainerRunnable(allocatedContainer, containerListener); Thread launchThread = new Thread(runnableLaunchContainer); // launch and start the container on a separate thread to keep // the main thread unblocked // as all containers may not be allocated at one go. launchThreads.add(launchThread); launchThread.start(); } } @Override public void onShutdownRequest() { done = true; } @Override public void onNodesUpdated(List<NodeReport> updatedNodes) {} @Override public float getProgress() { // set progress to deliver to RM on next heartbeat float progress = (float) numCompletedContainers.get() / numTotalContainers; return progress; } @Override public void onError(Throwable e) { done = true; amRMClient.stop(); } } @VisibleForTesting static class NMCallbackHandler implements NMClientAsync.CallbackHandler { private ConcurrentMap<ContainerId, Container> containers = new ConcurrentHashMap<ContainerId, Container>(); private final ApplicationMaster applicationMaster; public NMCallbackHandler(ApplicationMaster applicationMaster) { this.applicationMaster = applicationMaster; } public void addContainer(ContainerId containerId, Container container) { containers.putIfAbsent(containerId, container); } @Override public void onContainerStopped(ContainerId containerId) { if (LOG.isDebugEnabled()) { LOG.debug("Succeeded to stop Container " + containerId); } containers.remove(containerId); } @Override public void onContainerStatusReceived(ContainerId containerId, ContainerStatus containerStatus) { if (LOG.isDebugEnabled()) { LOG.debug("Container Status: id=" + containerId + ", status=" + containerStatus); } } @Override public void onContainerStarted(ContainerId containerId, Map<String, ByteBuffer> allServiceResponse) { if (LOG.isDebugEnabled()) { LOG.debug("Succeeded to start Container " + containerId); } Container container = containers.get(containerId); if (container != null) { applicationMaster.nmClientAsync.getContainerStatusAsync(containerId, container.getNodeId()); } } @Override public void onStartContainerError(ContainerId containerId, Throwable t) { LOG.error("Failed to start Container " + containerId); containers.remove(containerId); applicationMaster.numCompletedContainers.incrementAndGet(); applicationMaster.numFailedContainers.incrementAndGet(); } @Override public void onGetContainerStatusError( ContainerId containerId, Throwable t) { LOG.error("Failed to query the status of Container " + containerId); } @Override public void onStopContainerError(ContainerId containerId, Throwable t) { LOG.error("Failed to stop Container " + containerId); containers.remove(containerId); } } /** * Thread to connect to the {@link ContainerManagementProtocol} and launch the container * that will execute the shell command. */ private class LaunchContainerRunnable implements Runnable { // Allocated container Container container; NMCallbackHandler containerListener; /** * @param lcontainer Allocated container * @param containerListener Callback handler of the container */ public LaunchContainerRunnable( Container lcontainer, NMCallbackHandler containerListener) { this.container = lcontainer; this.containerListener = containerListener; } @Override /** * Connects to CM, sets up container launch context * for shell command and eventually dispatches the container * start request to the CM. */ public void run() { LOG.info("Setting up container launch container for containerid=" + container.getId()); ContainerLaunchContext ctx = Records .newRecord(ContainerLaunchContext.class); // Set the environment ctx.setEnvironment(shellEnv); // Set the local resources Map<String, LocalResource> localResources = new HashMap<String, LocalResource>(); // The container for the eventual shell commands needs its own local // resources too. // In this scenario, if a shell script is specified, we need to have it // copied and made available to the container. if (!shellScriptPath.isEmpty()) { LocalResource shellRsrc = Records.newRecord(LocalResource.class); shellRsrc.setType(LocalResourceType.FILE); shellRsrc.setVisibility(LocalResourceVisibility.APPLICATION); try { shellRsrc.setResource(ConverterUtils.getYarnUrlFromURI(new URI( shellScriptPath))); } catch (URISyntaxException e) { LOG.error("Error when trying to use shell script path specified" + " in env, path=" + shellScriptPath); e.printStackTrace(); // A failure scenario on bad input such as invalid shell script path // We know we cannot continue launching the container // so we should release it. // TODO numCompletedContainers.incrementAndGet(); numFailedContainers.incrementAndGet(); return; } shellRsrc.setTimestamp(shellScriptPathTimestamp); shellRsrc.setSize(shellScriptPathLen); localResources.put(ExecShellStringPath, shellRsrc); } ctx.setLocalResources(localResources); // Set the necessary command to execute on the allocated container Vector<CharSequence> vargs = new Vector<CharSequence>(5); // Set executable command vargs.add(shellCommand); // Set shell script path if (!shellScriptPath.isEmpty()) { vargs.add(ExecShellStringPath); } // Set args for the shell command if any vargs.add(shellArgs); // Add log redirect params vargs.add("1>" + ApplicationConstants.LOG_DIR_EXPANSION_VAR + "/stdout"); vargs.add("2>" + ApplicationConstants.LOG_DIR_EXPANSION_VAR + "/stderr"); // Get final commmand StringBuilder command = new StringBuilder(); for (CharSequence str : vargs) { command.append(str).append(" "); } List<String> commands = new ArrayList<String>(); commands.add(command.toString()); ctx.setCommands(commands); // Set up tokens for the container too. Today, for normal shell commands, // the container in distribute-shell doesn't need any tokens. We are // populating them mainly for NodeManagers to be able to download any // files in the distributed file-system. The tokens are otherwise also // useful in cases, for e.g., when one is running a "hadoop dfs" command // inside the distributed shell. ctx.setTokens(allTokens.duplicate()); containerListener.addContainer(container.getId(), container); nmClientAsync.startContainerAsync(container, ctx); } } /** * Setup the request that will be sent to the RM for the container ask. * * @return the setup ResourceRequest to be sent to RM */ private ContainerRequest setupContainerAskForRM() { // setup requirements for hosts // using * as any host will do for the distributed shell app // set the priority for the request Priority pri = Records.newRecord(Priority.class); // TODO - what is the range for priority? how to decide? pri.setPriority(requestPriority); // Set up resource type requirements // For now, only memory is supported so we set memory requirements Resource capability = Records.newRecord(Resource.class); capability.setMemory(containerMemory); ContainerRequest request = new ContainerRequest(capability, null, null, pri); LOG.info("Requested container ask: " + request.toString()); return request; } }