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.hadoop.mapred; import java.io.File; import java.io.FileOutputStream; import java.io.IOException; import java.io.PrintWriter; import java.util.TimerTask; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.mapred.TaskTrackerStatus.TaskTrackerHealthStatus; import junit.framework.TestCase; public class TestNodeHealthService extends TestCase { private static volatile Log LOG = LogFactory.getLog(TestNodeHealthService.class); private static final String nodeHealthConfigPath = System.getProperty("test.build.extraconf", "build/test/extraconf"); final static File nodeHealthConfigFile = new File(nodeHealthConfigPath, "mapred-site.xml"); private String testRootDir = new File(System.getProperty("test.build.data", "/tmp")).getAbsolutePath(); private File nodeHealthscriptFile = new File(testRootDir, "failingscript.sh"); @Override protected void tearDown() throws Exception { if (nodeHealthConfigFile.exists()) { nodeHealthConfigFile.delete(); } if (nodeHealthscriptFile.exists()) { nodeHealthscriptFile.delete(); } super.tearDown(); } private Configuration getConfForNodeHealthScript() { Configuration conf = new Configuration(); conf.set(NodeHealthCheckerService.HEALTH_CHECK_SCRIPT_PROPERTY, nodeHealthscriptFile.getAbsolutePath()); conf.setLong(NodeHealthCheckerService.HEALTH_CHECK_INTERVAL_PROPERTY, 500); conf.setLong(NodeHealthCheckerService.HEALTH_CHECK_FAILURE_INTERVAL_PROPERTY, 1000); return conf; } private void writeNodeHealthScriptFile(String scriptStr, boolean setExecutable) throws IOException { PrintWriter pw = new PrintWriter(new FileOutputStream(nodeHealthscriptFile)); pw.println(scriptStr); pw.flush(); pw.close(); nodeHealthscriptFile.setExecutable(setExecutable); } public void testNodeHealthScriptShouldRun() throws IOException { // Node health script should not start if there is no property called // node health script path. assertFalse("Health checker should not have started", NodeHealthCheckerService.shouldRun(new Configuration())); Configuration conf = getConfForNodeHealthScript(); // Node health script should not start if the node health script does not // exists assertFalse("Node health script should start", NodeHealthCheckerService.shouldRun(conf)); // Create script path. conf.writeXml(new FileOutputStream(nodeHealthConfigFile)); writeNodeHealthScriptFile("", false); // Node health script should not start if the node health script is not // executable. assertFalse("Node health script should start", NodeHealthCheckerService.shouldRun(conf)); writeNodeHealthScriptFile("", true); assertTrue("Node health script should start", NodeHealthCheckerService.shouldRun(conf)); } public void testNodeHealthScript() throws Exception { TaskTrackerHealthStatus healthStatus = new TaskTrackerHealthStatus(); String errorScript = "echo ERROR\n echo \"Tracker not healthy\""; String normalScript = "echo \"I am all fine\""; String timeOutScript = "sleep 4\n echo\"I am fine\""; Configuration conf = getConfForNodeHealthScript(); conf.writeXml(new FileOutputStream(nodeHealthConfigFile)); NodeHealthCheckerService nodeHealthChecker = new NodeHealthCheckerService(conf); TimerTask timer = nodeHealthChecker.getTimer(); writeNodeHealthScriptFile(normalScript, true); timer.run(); nodeHealthChecker.setHealthStatus(healthStatus); LOG.info("Checking initial healthy condition"); // Check proper report conditions. assertTrue("Node health status reported unhealthy", healthStatus.isNodeHealthy()); assertTrue("Node health status reported unhealthy", healthStatus.getHealthReport().isEmpty()); // write out error file. // Healthy to unhealthy transition writeNodeHealthScriptFile(errorScript, true); // Run timer timer.run(); // update health status nodeHealthChecker.setHealthStatus(healthStatus); LOG.info("Checking Healthy--->Unhealthy"); assertFalse("Node health status reported healthy", healthStatus.isNodeHealthy()); assertFalse("Node health status reported healthy", healthStatus.getHealthReport().isEmpty()); // Check unhealthy to healthy transitions. writeNodeHealthScriptFile(normalScript, true); timer.run(); nodeHealthChecker.setHealthStatus(healthStatus); LOG.info("Checking UnHealthy--->healthy"); // Check proper report conditions. assertTrue("Node health status reported unhealthy", healthStatus.isNodeHealthy()); assertTrue("Node health status reported unhealthy", healthStatus.getHealthReport().isEmpty()); // Healthy to timeout transition. writeNodeHealthScriptFile(timeOutScript, true); timer.run(); nodeHealthChecker.setHealthStatus(healthStatus); LOG.info("Checking Healthy--->timeout"); assertFalse("Node health status reported healthy even after timeout", healthStatus.isNodeHealthy()); assertEquals("Node time out message not propogated", healthStatus.getHealthReport(), NodeHealthCheckerService.NODE_HEALTH_SCRIPT_TIMED_OUT_MSG); } }