/**
* 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 org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.http.HttpServer;
import org.apache.hadoop.net.NetUtils;
import org.apache.hadoop.security.SecurityUtil;
import org.apache.hadoop.security.UserGroupInformation;
import org.apache.hadoop.util.StringUtils;
import org.mortbay.jetty.webapp.WebAppContext;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.net.URL;
import java.security.PrivilegedExceptionAction;
/******************************************************************
* {@link JobHistoryServer} is responsible for servicing all job history
* related requests from client.
*
* History Server can be initialized in one of two modes
* * Emdedded within {@link JobTracker}
* * External daemon, can either be run on the job tracker node or outside
*
* Two {@link Configuration} entries in mapred-site.xml govern the functioning
* of the history server
*
* mapred.job.history.server.http.address is address to which history web
* server is bound to. If operating in embedded mode, the hostname on
* history address has to be same as the job tracker host name
*
* mapred.job.history.server.embedded (default is true) will cause job tracker
* to init history server, else the server need to be started as a
* separate daemon process
*****************************************************************/
public class JobHistoryServer {
private static final Log LOG = LogFactory.getLog(JobHistoryServer.class);
static{
Configuration.addDefaultResource("mapred-default.xml");
Configuration.addDefaultResource("mapred-site.xml");
}
private static final String JH_USER_NAME =
"mapreduce.jobhistory.kerberos.principal";
private static final String JH_KEYTAB_FILE =
"mapreduce.jobhistory.keytab.file";
public static final String MAPRED_HISTORY_SERVER_HTTP_ADDRESS =
"mapreduce.history.server.http.address";
public static final String MAPRED_HISTORY_SERVER_EMBEDDED =
"mapreduce.history.server.embedded";
private HttpServer historyServer;
private JobConf conf;
private String historyInfoAddr;
private WebAppContext context;
/**
* Starts job history server as a independent process
* * Initializes ACL Manager
* * Starts a webapp to service history requests
*
* @param conf - Mr Cluster configuration
* @throws IOException - any exception starting history server
*/
public JobHistoryServer(JobConf conf) throws IOException {
if (isEmbedded(conf)) {
throw new IllegalStateException("History server is configured to run " +
"within JobTracker. Aborting..");
}
historyInfoAddr = getBindAddress(conf);
login(conf);
ACLsManager aclsManager = initializeACLsManager(conf);
historyServer = initializeWebContainer(conf, aclsManager);
initializeWebServer(conf, aclsManager);
}
/**
* Starts job history server as a embedded server within job tracker
* * Starts a webapp to service history requests
*
* @param conf - MR Cluster configuration
* @param aclsManager - ACLs Manager for user authentication
* @param httpServer - Http Server instance
* @throws IOException - any exception starting history server
*/
public JobHistoryServer(JobConf conf,
ACLsManager aclsManager,
HttpServer httpServer) throws IOException {
historyInfoAddr = getBindAddress(conf);
this.historyServer = httpServer;
initializeWebServer(conf, aclsManager);
}
private void login(JobConf conf) throws IOException {
UserGroupInformation.setConfiguration(conf);
InetSocketAddress infoSocAddr = NetUtils.createSocketAddr(historyInfoAddr);
SecurityUtil.login(conf, JH_KEYTAB_FILE, JH_USER_NAME, infoSocAddr.getHostName());
LOG.info("History server login successful");
}
private ACLsManager initializeACLsManager(JobConf conf)
throws IOException {
LOG.info("Initializing ACLs Manager");
Configuration queuesConf = new Configuration(conf);
QueueManager queueManager = new QueueManager(queuesConf);
return new ACLsManager(conf,
new JobACLsManager(conf), queueManager);
}
/**
* Start embedded jetty server to host history servlets/pages
* - Push history file system, acl Manager and cluster conf for future
* reference by the servlets/pages
*
* @param conf - Cluster configuration
* @param aclsManager - ACLs Manager for validating user request
* @throws IOException - Any exception while starting web server
*/
private void initializeWebServer(final JobConf conf,
ACLsManager aclsManager)
throws IOException {
this.conf = conf;
FileSystem fs;
try {
fs = aclsManager.getMROwner().
doAs(new PrivilegedExceptionAction<FileSystem>() {
public FileSystem run() throws IOException {
return FileSystem.get(conf);
}});
} catch (InterruptedException e) {
throw new IOException("Operation interrupted", e);
}
if (!isEmbedded(conf)) {
JobHistory.initDone(conf, fs, false);
}
final String historyLogDir =
JobHistory.getCompletedJobHistoryLocation().toString();
FileSystem historyFS = new Path(historyLogDir).getFileSystem(conf);
historyServer.setAttribute("historyLogDir", historyLogDir);
historyServer.setAttribute("fileSys", historyFS);
historyServer.setAttribute("jobConf", conf);
historyServer.setAttribute("aclManager", aclsManager);
historyServer.addServlet("historyfile", "/historyfile",
RawHistoryFileServlet.class);
}
private HttpServer initializeWebContainer(JobConf conf,
ACLsManager aclsManager)
throws IOException {
InetSocketAddress infoSocAddr = NetUtils.createSocketAddr(historyInfoAddr);
int tmpInfoPort = infoSocAddr.getPort();
return new HttpServer("history", infoSocAddr.getHostName(),
tmpInfoPort, tmpInfoPort == 0, conf, aclsManager.getAdminsAcl());
}
public void start() throws IOException {
if (!isEmbedded(conf)) {
historyServer.start();
}
InetSocketAddress infoSocAddr = NetUtils.createSocketAddr(historyInfoAddr);
conf.set(MAPRED_HISTORY_SERVER_HTTP_ADDRESS, infoSocAddr.getHostName() +
":" + historyServer.getPort());
LOG.info("Started job history server at: " + getAddress(conf));
}
public void join() throws InterruptedException {
historyServer.join();
}
/**
* Shutsdown the history server if already initialized
* @throws Exception - Any exception during shutdown
*/
public void shutdown() throws Exception {
if (historyServer != null && !isEmbedded(conf)) {
LOG.info("Shutting down history server");
historyServer.stop();
}
}
/**
* Start job history server as an independent process
*
* @param args - Command line arguments
*/
public static void main(String[] args) {
StringUtils.startupShutdownMessage(JobHistoryServer.class, args, LOG);
try {
JobHistoryServer server = new JobHistoryServer(new JobConf());
server.start();
server.join();
} catch (Throwable e) {
LOG.fatal(StringUtils.stringifyException(e));
System.exit(-1);
}
}
static boolean isEmbedded(JobConf conf) {
return conf.getBoolean(MAPRED_HISTORY_SERVER_EMBEDDED, true);
}
static String getAddress(JobConf conf) {
return conf.get(MAPRED_HISTORY_SERVER_HTTP_ADDRESS);
}
static String getHistoryUrlPrefix(JobConf conf) {
return (isEmbedded(conf) ? "" : "http://" + getAddress(conf));
}
private static String getBindAddress(JobConf conf) {
return conf.get(MAPRED_HISTORY_SERVER_HTTP_ADDRESS, "localhost:0");
}
}