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.client.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.ContextHandler; 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; /** * This class sets up the web-server that serves the web frontend. It instantiates and * configures an embedded jetty server. */ public class WebInterfaceServer { /** * The log for this class. */ private static final Log LOG = LogFactory.getLog(WebInterfaceServer.class); /** * The jetty server serving all requests. */ private final Server server; /** * Creates a new web interface server. The server runs the servlets that implement the logic * to upload, list, delete and submit jobs, to compile them and to show the optimizer plan. * It serves the asynchronous requests for the plans and all other static resources, like * static web pages, stylesheets or javascript files. * * @param nepheleConfig * The configuration for the nephele job manager. All compiled jobs will be sent * to the manager described by this configuration. * @param port * The port to launch the server on. * @throws IOException * Thrown, if the server setup failed for an I/O related reason. */ public WebInterfaceServer(Configuration nepheleConfig, int port) throws IOException { Configuration config = GlobalConfiguration.getConfiguration(); // if no explicit configuration is given, use the global configuration if (nepheleConfig == null) { nepheleConfig = config; } // get base path of Stratosphere installation String basePath = nepheleConfig.getString(ConfigConstants.STRATOSPHERE_BASE_DIR_PATH_KEY, ""); File webDir; File tmpDir; File uploadDir; File planDumpDir; String webDirPath = config.getString(ConfigConstants.WEB_ROOT_PATH_KEY, ConfigConstants.DEFAULT_WEB_ROOT_DIR); if (webDirPath.startsWith("/")) { // absolute path webDir = new File(webDirPath); } else { // path relative to base dir webDir = new File(basePath + "/" + webDirPath); } String tmpDirPath = config.getString(ConfigConstants.WEB_TMP_DIR_KEY, ConfigConstants.DEFAULT_WEB_TMP_DIR); tmpDir = new File(tmpDirPath); if (tmpDir.isAbsolute()) { // absolute path, everything all right } else { // path relative to base dir tmpDir = new File(basePath + "/" + tmpDirPath); } String uploadDirPath = config.getString(ConfigConstants.WEB_JOB_UPLOAD_DIR_KEY, ConfigConstants.DEFAULT_WEB_JOB_STORAGE_DIR); uploadDir = new File(uploadDirPath); if (uploadDir.isAbsolute()) { // absolute path, everything peachy } else { // path relative to base dir uploadDir = new File(basePath + "/" + uploadDirPath); } String planDumpDirPath = config.getString(ConfigConstants.WEB_PLAN_DUMP_DIR_KEY, ConfigConstants.DEFAULT_WEB_PLAN_DUMP_DIR); planDumpDir = new File(planDumpDirPath); if (planDumpDir.isAbsolute()) { // absolute path, nice and dandy } else { // path relative to base dir planDumpDir = new File(basePath + "/" + planDumpDirPath); } if (LOG.isInfoEnabled()) { LOG.info( "Setting up web frontend server, using web-root directory '" + webDir.getAbsolutePath() + "'."); LOG.info("Web frontend server will store temporary files in '" + tmpDir.getAbsolutePath() + "', uploaded jobs in '" + uploadDir.getAbsolutePath() + "', plan-json-dumps in '" + planDumpDir.getAbsolutePath() + "'."); LOG.info("Web-frontend will submit jobs to nephele job-manager on " + config.getString(ConfigConstants.JOB_MANAGER_IPC_ADDRESS_KEY, null) + ", port " + config.getInteger(ConfigConstants.JOB_MANAGER_IPC_PORT_KEY, ConfigConstants.DEFAULT_JOB_MANAGER_IPC_PORT) + "."); } server = new Server(port); // ensure that the directory with the web documents exists if (!webDir.exists()) { throw new FileNotFoundException( "The directory containing the web documents does not exist: " + webDir.getAbsolutePath()); } // ensure, that all the directories exist checkAndCreateDirectories(tmpDir, true); checkAndCreateDirectories(uploadDir, true); checkAndCreateDirectories(planDumpDir, true); int jobManagerWebPort = config.getInteger(ConfigConstants.JOB_MANAGER_WEB_PORT_KEY, ConfigConstants.DEFAULT_JOB_MANAGER_WEB_FRONTEND_PORT); // ----- the handlers for the servlets ----- ServletContextHandler servletContext = new ServletContextHandler(ServletContextHandler.SESSIONS); servletContext.setContextPath("/"); servletContext.addServlet(new ServletHolder(new PactJobJSONServlet(uploadDir)), "/pactPlan"); servletContext.addServlet(new ServletHolder(new JobsInfoServlet(nepheleConfig)), "/jobsInfo"); servletContext.addServlet(new ServletHolder(new PlanDisplayServlet(jobManagerWebPort)), "/showPlan"); servletContext.addServlet(new ServletHolder(new JobsServlet(uploadDir, tmpDir, "launch.html")), "/jobs"); servletContext.addServlet( new ServletHolder(new JobSubmissionServlet(nepheleConfig, uploadDir, planDumpDir)), "/runJob"); // ----- the hander serving the written pact plans ----- ResourceHandler pactPlanHandler = new ResourceHandler(); pactPlanHandler.setDirectoriesListed(false); pactPlanHandler.setResourceBase(planDumpDir.getAbsolutePath()); ContextHandler pactPlanContext = new ContextHandler(); pactPlanContext.setContextPath("/ajax-plans"); pactPlanContext.setHandler(pactPlanHandler); // ----- 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(pactPlanContext); handlers.addHandler(resourceHandler); // ----- create the login module with http authentication ----- File af = null; String authFile = config.getString(ConfigConstants.WEB_ACCESS_FILE_KEY, ConfigConstants.DEFAULT_WEB_ACCESS_FILE_PATH); 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 Query Engine 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 { server.start(); } /** * Lets the calling thread wait until the server terminates its operation. * * @throws InterruptedException * Thrown, if the calling thread is interrupted. */ public void join() throws InterruptedException { server.join(); } /** * Checks and creates the directory described by the abstract directory path. This function checks * if the directory exists and creates it if necessary. It also checks read permissions and * write permission, if necessary. * * @param dir * The String describing the directory path. * @param needWritePermission * A flag indicating whether to check write access. * @throws IOException * Thrown, if the directory could not be created, or if one of the checks failed. */ private final void checkAndCreateDirectories(File f, boolean needWritePermission) throws IOException { String dir = f.getAbsolutePath(); // check if it exists and it is not a directory if (f.exists() && !f.isDirectory()) { throw new IOException("A none directory file with the same name as the configured directory '" + dir + "' already exists."); } // try to create the directory if (!f.exists()) { if (!f.mkdirs()) { throw new IOException("Could not create the directory '" + dir + "'."); } } // check the read and execute permission if (!(f.canRead() && f.canExecute())) { throw new IOException("The directory '" + dir + "' cannot be read and listed."); } // check the write permission if (needWritePermission && !f.canWrite()) { throw new IOException("No write access could be obtained on directory '" + dir + "'."); } } }