Java tutorial
/*********************************************************************************************************************** * Copyright (C) 2010-2013 by the Stratosphere project (http://stratosphere.eu) * * Licensed 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 eu.stratosphere.nephele.jobmanager.web; import java.io.File; import java.io.FileNotFoundException; import java.io.IOException; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.eclipse.jetty.http.security.Constraint; import org.eclipse.jetty.security.ConstraintMapping; import org.eclipse.jetty.security.ConstraintSecurityHandler; import org.eclipse.jetty.security.HashLoginService; import org.eclipse.jetty.security.authentication.BasicAuthenticator; import org.eclipse.jetty.server.Server; import org.eclipse.jetty.server.handler.HandlerList; import org.eclipse.jetty.server.handler.ResourceHandler; import org.eclipse.jetty.servlet.ServletContextHandler; import org.eclipse.jetty.servlet.ServletHolder; import eu.stratosphere.configuration.ConfigConstants; import eu.stratosphere.configuration.Configuration; import eu.stratosphere.configuration.GlobalConfiguration; import eu.stratosphere.nephele.jobmanager.JobManager; /** * This class sets up a web-server that contains a web frontend to display information about running jobs. * It instantiates and configures an embedded jetty server. */ public class WebInfoServer { /** * The log for this class. */ private static final Log LOG = LogFactory.getLog(WebInfoServer.class); /** * The jetty server serving all requests. */ private final Server server; /** * Port for info server */ private int port; /** * Creates a new web info server. The server runs the servlets that implement the logic * to list all present information concerning the job manager * * @param nepheleConfig * The configuration for the nephele job manager. * @param port * The port to launch the server on. * @throws IOException * Thrown, if the server setup failed for an I/O related reason. */ public WebInfoServer(Configuration nepheleConfig, int port, JobManager jobmanager) throws IOException { this.port = port; // if no explicit configuration is given, use the global configuration if (nepheleConfig == null) { nepheleConfig = GlobalConfiguration.getConfiguration(); } // get base path of Stratosphere installation String basePath = nepheleConfig.getString(ConfigConstants.STRATOSPHERE_BASE_DIR_PATH_KEY, ""); String webDirPath = nepheleConfig.getString(ConfigConstants.JOB_MANAGER_WEB_ROOT_PATH_KEY, ConfigConstants.DEFAULT_JOB_MANAGER_WEB_ROOT_PATH); String logDirPath = nepheleConfig.getString(ConfigConstants.JOB_MANAGER_WEB_LOG_PATH_KEY, basePath + "/log"); File webDir; if (webDirPath.startsWith("/")) { // absolute path webDir = new File(webDirPath); } else { // path relative to base dir webDir = new File(basePath + "/" + webDirPath); } if (LOG.isInfoEnabled()) { LOG.info("Setting up web info server, using web-root directory '" + webDir.getAbsolutePath() + "'."); //LOG.info("Web info server will store temporary files in '" + tmpDir.getAbsolutePath()); LOG.info("Web info server will display information about nephele job-manager on " + nepheleConfig.getString(ConfigConstants.JOB_MANAGER_IPC_ADDRESS_KEY, null) + ", port " + port + "."); } // ensure that the directory with the web documents exists if (!webDir.exists()) { throw new FileNotFoundException( "Cannot start jobmanager web info server. The directory containing the web documents does not exist: " + webDir.getAbsolutePath()); } server = new Server(port); // ----- the handlers for the servlets ----- ServletContextHandler servletContext = new ServletContextHandler(ServletContextHandler.SESSIONS); servletContext.setContextPath("/"); servletContext.addServlet(new ServletHolder(new JobmanagerInfoServlet(jobmanager)), "/jobsInfo"); servletContext.addServlet(new ServletHolder(new LogfileInfoServlet(new File(logDirPath))), "/logInfo"); // ----- the handler serving all the static files ----- ResourceHandler resourceHandler = new ResourceHandler(); resourceHandler.setDirectoriesListed(false); resourceHandler.setResourceBase(webDir.getAbsolutePath()); // ----- add the handlers to the list handler ----- HandlerList handlers = new HandlerList(); handlers.addHandler(servletContext); handlers.addHandler(resourceHandler); // ----- create the login module with http authentication ----- File af = null; String authFile = nepheleConfig.getString(ConfigConstants.JOB_MANAGER_WEB_ACCESS_FILE_KEY, null); if (authFile != null) { af = new File(authFile); if (!af.exists()) { LOG.error("The specified file '" + af.getAbsolutePath() + "' with the authentication information is missing. Starting server without HTTP authentication."); af = null; } } if (af != null) { HashLoginService loginService = new HashLoginService("Stratosphere Jobmanager Interface", authFile); server.addBean(loginService); Constraint constraint = new Constraint(); constraint.setName(Constraint.__BASIC_AUTH); constraint.setAuthenticate(true); constraint.setRoles(new String[] { "user" }); ConstraintMapping mapping = new ConstraintMapping(); mapping.setPathSpec("/*"); mapping.setConstraint(constraint); ConstraintSecurityHandler sh = new ConstraintSecurityHandler(); sh.addConstraintMapping(mapping); sh.setAuthenticator(new BasicAuthenticator()); sh.setLoginService(loginService); sh.setStrict(true); // set the handers: the server hands the request to the security handler, // which hands the request to the other handlers when authenticated sh.setHandler(handlers); server.setHandler(sh); } else { server.setHandler(handlers); } } /** * Starts the web frontend server. * * @throws Exception * Thrown, if the start fails. */ public void start() throws Exception { LOG.info("Starting web info server for JobManager on port " + this.port); server.start(); } }