Java tutorial
/* * 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.flink.yarn; import org.apache.flink.configuration.ConfigConstants; import org.apache.flink.configuration.Configuration; import org.apache.flink.configuration.GlobalConfiguration; import org.apache.flink.configuration.SecurityOptions; import org.apache.flink.core.fs.FileSystem; import org.apache.flink.runtime.clusterframework.types.ResourceID; import org.apache.flink.runtime.highavailability.HighAvailabilityServices; import org.apache.flink.runtime.highavailability.HighAvailabilityServicesUtils; import org.apache.flink.runtime.metrics.MetricRegistry; import org.apache.flink.runtime.metrics.MetricRegistryConfiguration; import org.apache.flink.runtime.rpc.RpcService; import org.apache.flink.runtime.security.SecurityUtils; import org.apache.flink.runtime.taskexecutor.TaskManagerRunner; import org.apache.flink.runtime.util.EnvironmentInformation; import org.apache.flink.runtime.util.JvmShutdownSafeguard; import org.apache.flink.runtime.util.SignalHandler; import org.apache.flink.util.Preconditions; import org.apache.hadoop.fs.CommonConfigurationKeysPublic; import org.apache.hadoop.security.UserGroupInformation; import org.apache.hadoop.yarn.api.ApplicationConstants.Environment; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import java.io.File; import java.util.Map; import java.util.concurrent.Callable; /** * This class is the executable entry point for running a TaskExecutor in a YARN container. */ public class YarnTaskExecutorRunner { /** Logger */ protected static final Logger LOG = LoggerFactory.getLogger(YarnTaskExecutorRunner.class); /** The process environment variables */ private static final Map<String, String> ENV = System.getenv(); /** The exit code returned if the initialization of the yarn task executor runner failed */ private static final int INIT_ERROR_EXIT_CODE = 31; private MetricRegistry metricRegistry; private HighAvailabilityServices haServices; private RpcService taskExecutorRpcService; private TaskManagerRunner taskManagerRunner; // ------------------------------------------------------------------------ // Program entry point // ------------------------------------------------------------------------ /** * The entry point for the YARN task executor runner. * * @param args The command line arguments. */ public static void main(String[] args) { EnvironmentInformation.logEnvironmentInfo(LOG, "YARN TaskExecutor runner", args); SignalHandler.register(LOG); JvmShutdownSafeguard.installAsShutdownHook(LOG); // run and exit with the proper return code int returnCode = new YarnTaskExecutorRunner().run(args); System.exit(returnCode); } /** * The instance entry point for the YARN task executor. Obtains user group * information and calls the main work method {@link #runTaskExecutor(org.apache.flink.configuration.Configuration)} as a * privileged action. * * @param args The command line arguments. * @return The process exit code. */ protected int run(String[] args) { try { LOG.debug("All environment variables: {}", ENV); final String yarnClientUsername = ENV.get(YarnConfigKeys.ENV_HADOOP_USER_NAME); final String localDirs = ENV.get(Environment.LOCAL_DIRS.key()); LOG.info("Current working/local Directory: {}", localDirs); final String currDir = ENV.get(Environment.PWD.key()); LOG.info("Current working Directory: {}", currDir); final String remoteKeytabPath = ENV.get(YarnConfigKeys.KEYTAB_PATH); LOG.info("TM: remote keytab path obtained {}", remoteKeytabPath); final String remoteKeytabPrincipal = ENV.get(YarnConfigKeys.KEYTAB_PRINCIPAL); LOG.info("TM: remote keytab principal obtained {}", remoteKeytabPrincipal); final Configuration configuration = GlobalConfiguration.loadConfiguration(currDir); FileSystem.setDefaultScheme(configuration); // configure local directory String flinkTempDirs = configuration.getString(ConfigConstants.TASK_MANAGER_TMP_DIR_KEY, null); if (flinkTempDirs == null) { LOG.info("Setting directories for temporary file " + localDirs); configuration.setString(ConfigConstants.TASK_MANAGER_TMP_DIR_KEY, localDirs); } else { LOG.info("Overriding YARN's temporary file directories with those " + "specified in the Flink config: " + flinkTempDirs); } // tell akka to die in case of an error configuration.setBoolean(ConfigConstants.AKKA_JVM_EXIT_ON_FATAL_ERROR, true); String keytabPath = null; if (remoteKeytabPath != null) { File f = new File(currDir, Utils.KEYTAB_FILE_NAME); keytabPath = f.getAbsolutePath(); LOG.info("keytab path: {}", keytabPath); } UserGroupInformation currentUser = UserGroupInformation.getCurrentUser(); LOG.info("YARN daemon is running as: {} Yarn client user obtainer: {}", currentUser.getShortUserName(), yarnClientUsername); org.apache.hadoop.conf.Configuration hadoopConfiguration = null; //To support Yarn Secure Integration Test Scenario File krb5Conf = new File(currDir, Utils.KRB5_FILE_NAME); if (krb5Conf.exists() && krb5Conf.canRead()) { String krb5Path = krb5Conf.getAbsolutePath(); LOG.info("KRB5 Conf: {}", krb5Path); hadoopConfiguration = new org.apache.hadoop.conf.Configuration(); hadoopConfiguration.set(CommonConfigurationKeysPublic.HADOOP_SECURITY_AUTHENTICATION, "kerberos"); hadoopConfiguration.set(CommonConfigurationKeysPublic.HADOOP_SECURITY_AUTHORIZATION, "true"); } SecurityUtils.SecurityConfiguration sc; if (hadoopConfiguration != null) { sc = new SecurityUtils.SecurityConfiguration(configuration, hadoopConfiguration); } else { sc = new SecurityUtils.SecurityConfiguration(configuration); } if (keytabPath != null && remoteKeytabPrincipal != null) { configuration.setString(SecurityOptions.KERBEROS_LOGIN_KEYTAB, keytabPath); configuration.setString(SecurityOptions.KERBEROS_LOGIN_PRINCIPAL, remoteKeytabPrincipal); } SecurityUtils.install(sc); return SecurityUtils.getInstalledContext().runSecured(new Callable<Integer>() { @Override public Integer call() throws Exception { return runTaskExecutor(configuration); } }); } catch (Throwable t) { // make sure that everything whatever ends up in the log LOG.error("YARN Application Master initialization failed", t); return INIT_ERROR_EXIT_CODE; } } // ------------------------------------------------------------------------ // Core work method // ------------------------------------------------------------------------ /** * The main work method, must run as a privileged action. * * @return The return code for the Java process. */ protected int runTaskExecutor(Configuration config) { try { // ---- (1) create common services // first get the ResouceId, resource id is the container id for yarn. final String containerId = ENV.get(YarnFlinkResourceManager.ENV_FLINK_CONTAINER_ID); Preconditions.checkArgument(containerId != null, "ContainerId variable %s not set", YarnFlinkResourceManager.ENV_FLINK_CONTAINER_ID); // use the hostname passed by job manager final String taskExecutorHostname = ENV.get(YarnResourceManager.ENV_FLINK_NODE_ID); if (taskExecutorHostname != null) { config.setString(ConfigConstants.TASK_MANAGER_HOSTNAME_KEY, taskExecutorHostname); } ResourceID resourceID = new ResourceID(containerId); LOG.info("YARN assigned resource id {} for the task executor.", resourceID.toString()); haServices = HighAvailabilityServicesUtils.createAvailableOrEmbeddedServices(config); metricRegistry = new MetricRegistry(MetricRegistryConfiguration.fromConfiguration(config)); // ---- (2) init task manager runner ------- taskExecutorRpcService = TaskManagerRunner.createRpcService(config, haServices); taskManagerRunner = new TaskManagerRunner(config, resourceID, taskExecutorRpcService, haServices, metricRegistry); // ---- (3) start the task manager runner taskManagerRunner.start(); LOG.debug("YARN task executor started"); taskManagerRunner.getTerminationFuture().get(); // everything started, we can wait until all is done or the process is killed LOG.info("YARN task manager runner finished"); shutdown(); } catch (Throwable t) { // make sure that everything whatever ends up in the log LOG.error("YARN task executor initialization failed", t); shutdown(); return INIT_ERROR_EXIT_CODE; } return 0; } // ------------------------------------------------------------------------ // Utilities // ------------------------------------------------------------------------ protected void shutdown() { if (taskExecutorRpcService != null) { try { taskExecutorRpcService.stopService(); } catch (Throwable tt) { LOG.error("Error shutting down job master rpc service", tt); } } if (haServices != null) { try { haServices.close(); } catch (Throwable tt) { LOG.warn("Failed to stop the HA service", tt); } } if (metricRegistry != null) { try { metricRegistry.shutdown(); } catch (Throwable tt) { LOG.warn("Failed to stop the metrics registry", tt); } } } }