/*
 * 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.runtime.metrics;

import akka.actor.ActorRef;
import akka.actor.ActorSystem;
import akka.actor.Props;
import akka.testkit.JavaTestKit;

import org.apache.flink.configuration.Configuration;
import org.apache.flink.runtime.akka.AkkaUtils;
import org.apache.flink.runtime.clusterframework.types.ResourceID;
import org.apache.flink.runtime.highavailability.HighAvailabilityServices;
import org.apache.flink.runtime.highavailability.nonha.embedded.EmbeddedHaServices;
import org.apache.flink.runtime.jobmanager.JobManager;
import org.apache.flink.runtime.jobmanager.MemoryArchivist;
import org.apache.flink.runtime.messages.TaskManagerMessages;
import org.apache.flink.runtime.taskexecutor.TaskManagerConfiguration;
import org.apache.flink.runtime.taskexecutor.TaskManagerServices;
import org.apache.flink.runtime.taskexecutor.TaskManagerServicesConfiguration;
import org.apache.flink.runtime.taskmanager.TaskManager;

import org.apache.flink.runtime.testingUtils.TestingUtils;
import org.apache.flink.util.TestLogger;
import org.junit.Assert;
import org.junit.Test;

import scala.concurrent.duration.FiniteDuration;

import java.net.InetAddress;
import java.util.UUID;
import java.util.concurrent.TimeUnit;

public class TaskManagerMetricsTest extends TestLogger {

	/**
	 * Tests the metric registry life cycle on JobManager re-connects.
	 */
	@Test
	public void testMetricRegistryLifeCycle() throws Exception {
		ActorSystem actorSystem = null;

		HighAvailabilityServices highAvailabilityServices = new EmbeddedHaServices(TestingUtils.defaultExecutor());

		try {
			actorSystem = AkkaUtils.createLocalActorSystem(new Configuration());

			// ================================================================
			// Start JobManager
			// ================================================================
			final ActorRef jobManager = JobManager.startJobManagerActors(
				new Configuration(),
				actorSystem,
				TestingUtils.defaultExecutor(),
				TestingUtils.defaultExecutor(),
				highAvailabilityServices,
				JobManager.class,
				MemoryArchivist.class)._1();

			// ================================================================
			// Start TaskManager
			// ================================================================
			final Configuration config = new Configuration();
			final ResourceID tmResourceID = ResourceID.generate();

			TaskManagerServicesConfiguration taskManagerServicesConfiguration = 
					TaskManagerServicesConfiguration.fromConfiguration(config, InetAddress.getLocalHost(), false);

			TaskManagerConfiguration taskManagerConfiguration = TaskManagerConfiguration.fromConfiguration(config);

			TaskManagerServices taskManagerServices = TaskManagerServices.fromConfiguration(
					taskManagerServicesConfiguration, tmResourceID);

			final MetricRegistry tmRegistry = taskManagerServices.getMetricRegistry();
			
			// create the task manager
			final Props tmProps = TaskManager.getTaskManagerProps(
				TaskManager.class,
				taskManagerConfiguration,
				tmResourceID,
				taskManagerServices.getTaskManagerLocation(),
				taskManagerServices.getMemoryManager(),
				taskManagerServices.getIOManager(),
				taskManagerServices.getNetworkEnvironment(),
				highAvailabilityServices,
				tmRegistry);

			final ActorRef taskManager = actorSystem.actorOf(tmProps);

			new JavaTestKit(actorSystem) {{
				new Within(new FiniteDuration(5000, TimeUnit.SECONDS)) {
					@Override
					protected void run() {
						taskManager.tell(TaskManagerMessages.getNotifyWhenRegisteredAtJobManagerMessage(),
							getTestActor());

						// wait for the TM to be registered
						TaskManagerMessages.RegisteredAtJobManager registeredAtJobManager = expectMsgClass(TaskManagerMessages.RegisteredAtJobManager.class);
						UUID leaderId = registeredAtJobManager.leaderId();

						// trigger re-registration of TM; this should include a disconnect from the current JM
						taskManager.tell(
							new TaskManagerMessages.JobManagerLeaderAddress(
								jobManager.path().toString(),
								leaderId),
							jobManager);

						// wait for re-registration to be completed
						taskManager.tell(TaskManagerMessages.getNotifyWhenRegisteredAtJobManagerMessage(),
							getTestActor());

						expectMsgClass(TaskManagerMessages.RegisteredAtJobManager.class);
					}
				};
			}};

			// verify that the registry was not shutdown due to the disconnect
			Assert.assertFalse(tmRegistry.isShutdown());

			// shut down the actors and the actor system
			actorSystem.shutdown();
			actorSystem.awaitTermination();
		} finally {
			if (actorSystem != null) {
				actorSystem.shutdown();
			}

			if (highAvailabilityServices != null) {
				highAvailabilityServices.closeAndCleanupAllData();
			}
		}
	}
}