sandbox-apis/virtualbox/src/main/java/org/jclouds/virtualbox/functions/admin/StartJettyIfNotAlreadyRunning.java

/**
 * Licensed to jclouds, Inc. (jclouds) under one or more
 * contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  jclouds 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.jclouds.virtualbox.functions.admin;

import static com.google.common.base.Preconditions.checkNotNull;

import javax.annotation.Resource;
import javax.inject.Inject;
import javax.inject.Named;

import org.eclipse.jetty.server.Handler;
import org.eclipse.jetty.server.Server;
import org.eclipse.jetty.server.handler.DefaultHandler;
import org.eclipse.jetty.server.handler.HandlerList;
import org.eclipse.jetty.server.handler.ResourceHandler;
import org.jclouds.compute.reference.ComputeServiceConstants;
import org.jclouds.javax.annotation.Nullable;
import org.jclouds.logging.Logger;
import org.jclouds.net.IPSocket;
import org.jclouds.predicates.InetSocketAddressConnect;
import org.jclouds.virtualbox.config.VirtualBoxConstants;

import com.google.common.base.Function;
import com.google.inject.Singleton;

/**
 * @author Andrea Turli
 */
public class StartJettyIfNotAlreadyRunning implements Function<String, Server> {

   @Resource
   @Named(ComputeServiceConstants.COMPUTE_LOGGER)
   protected Logger logger = Logger.NULL;

   private final Server jetty;
   private final int port;

   public StartJettyIfNotAlreadyRunning(Server jetty, @Named(VirtualBoxConstants.VIRTUALBOX_JETTY_PORT) int port) {
      this.jetty = checkNotNull(jetty, "jetty");
      this.port = port;
   }

   // TODO: getting an instance of the Server object should really be done in
   // Guice, so inside a *Module class, perhaps as a @Provides method
   @Inject
   public StartJettyIfNotAlreadyRunning(@Named(VirtualBoxConstants.VIRTUALBOX_JETTY_PORT) int port) {
      this(ServerJetty.getInstance().getServer(), port);
   }

   @Override
   public Server apply(@Nullable String baseResource) {
      if (!jetty.getState().equals(Server.STARTED)
            // TODO code smell = hard coding addresses or ports!!
            && !new InetSocketAddressConnect().apply(new IPSocket("localhost", port))) {
         ResourceHandler resource_handler = new ResourceHandler();
         resource_handler.setDirectoriesListed(true);
         resource_handler.setWelcomeFiles(new String[] { "index.html" });

         resource_handler.setResourceBase(baseResource);
         logger.info("serving " + resource_handler.getBaseResource());

         HandlerList handlers = new HandlerList();
         handlers.setHandlers(new Handler[] { resource_handler, new DefaultHandler() });
         jetty.setHandler(handlers);

         try {
            jetty.start();
         } catch (Exception e) {
            logger.error(e, "Server jetty could not be started at this %s", baseResource);
         }
         return jetty;
      } else {
         logger.debug("Server jetty serving %s already running. Skipping start", baseResource);
         return jetty;
      }

   }

   @Singleton
   private static class ServerJetty {
      private static ServerJetty instance;
      private Server server;
      private String port = System.getProperty(VirtualBoxConstants.VIRTUALBOX_JETTY_PORT, "8080");

      private ServerJetty() {
         this.server = new Server(Integer.parseInt(port));
      }

      public static ServerJetty getInstance() {
         if (instance == null)
            instance = new ServerJetty();
         return instance;
      }

      public Server getServer() {
         return server;
      }
   }
}