src/com/google/enterprise/adaptor/Service.java - plexi - Git at Google

 // Copyright 2014 Google Inc. All Rights Reserved.
 //
 // 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 com.google.enterprise.adaptor;

 import com.sun.net.httpserver.HttpContext;
 import com.sun.net.httpserver.HttpServer;

 import java.io.File;
 import java.io.IOException;
 import java.net.URI;
 import java.util.Arrays;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentMap;
 import java.util.concurrent.TimeUnit;
 import java.util.logging.Level;
 import java.util.logging.Logger;

 /**
  * Provides environment for running multiple adaptors on the same port and
  * having each instance be managed.
  */
 // TODO(ejona): improve locking
 // TODO(ejona): improve shutdown while starting
 // TODO(ejona): improve handling of time limits
 // TODO(ejona): improve state pre-condition checking
 public final class Service {
   private static final Logger log = Logger.getLogger(Service.class.getName());

   private final Config config;
   private final HttpServer server;
   private final HttpServer dashboardServer;
   private final ConcurrentMap<String, Instance> instances
       = new ConcurrentHashMap<String, Instance>();
   private final Thread shutdownHook
       = new Thread(new ShutdownHook(), "service-shutdown");
   private int index;

   private Service(Config config) throws IOException {
     this.config = config;
     this.server = Application.createHttpServer(config);
     this.dashboardServer = Application.createDashboardHttpServer(config);
   }

   public synchronized Instance createInstance(String name, File jar,
       File workingDir) {
     Instance instance = new Instance(name, jar, workingDir, index++);
     if (instances.putIfAbsent(name, instance) != null) {
       throw new IllegalArgumentException("Instance by name already present: "
           + name);
     }
     instance.install();
     return instance;
   }

   public synchronized void deleteInstance(String name, long time,
       TimeUnit unit) {
     Instance instance = instances.get(name);
     if (instance == null) {
       throw new IllegalArgumentException("No instance with name: " + name);
     }
     instance.stop(time, unit);
     instance.uninstall();
     instances.remove(name, instance);
   }

   public synchronized void start() throws IOException {
     daemonInit();
     // The shutdown hook is purposefully not part of the daemon methods,
     // because it should only be done when running from the command line.
     Runtime.getRuntime().addShutdownHook(shutdownHook);
     daemonStart();
   }

   synchronized void daemonInit() {
     server.start();
     dashboardServer.start();
   }

   synchronized void daemonStart() {
     for (Instance instance : instances.values()) {
       instance.start();
     }
   }

   public synchronized void stop(long time, TimeUnit unit) {
     daemonStop(time, unit);
     daemonDestroy(time, unit);
     try {
       Runtime.getRuntime().removeShutdownHook(shutdownHook);
     } catch (IllegalStateException ex) {
       // Already executing hook.
     }
   }

   synchronized void daemonStop(long time, TimeUnit unit) {
     for (Instance instance : instances.values()) {
       instance.stop(time, unit);
     }
   }

   synchronized void daemonDestroy(long time, TimeUnit unit) {
     Application.httpServerShutdown(server, time, unit);
     Application.httpServerShutdown(dashboardServer, time, unit);
   }

   static Service daemonMain(String[] args) throws IOException {
     Config config = new Config();
     Application.autoConfig(config, args,
         new File(Application.DEFAULT_CONFIG_FILE));
     return new Service(config);
   }

   public static void main(String[] args) throws IOException {
     Service service = daemonMain(args);
     // TODO(ejona): decide if we want the JAR to be relative to the parent
     // process or the child process (right now it is relative to the child).
     service.createInstance("adaptor1", new File("../AdaptorTemplate.jar"),
         new File("adaptor1"));
     service.createInstance("adaptor2", new File("../AdaptorTemplate.jar"),
         new File("adaptor2"));
     service.start();
   }

   /**
    * Maybe use this as an interface to allow disabling/enabling and
    * starting/stopping of particular instances?
    */
   public final class Instance {
     private final String name;
     private final File jar;
     private final File workingDir;
     private final int index;
     private Thread running;
     private ShutdownWaiter waiter;

     private Instance(String name, File jar, File workingDir, int index) {
       if (name == null) {
         throw new NullPointerException();
       }
       if (name.contains("/") || name.startsWith(".")) {
         // Prevent '.', '..', and things containing '/' from being names.
         throw new IllegalArgumentException(
             "Name must not contain / or start with .");
       }
       if (jar == null) {
         throw new NullPointerException();
       }
       if (index < 0 || index > 10000) {
         throw new IllegalArgumentException("Index too large or small: "
             + index);
       }
       this.name = name;
       this.jar = jar;
       this.workingDir = workingDir;
       this.index = index;
     }

     private void install() {
       // TODO(ejona): add disable support, where we return Service Unavailable
       // instead of Not Found.
     }

     private void start() {
       if (running != null) {
         throw new IllegalStateException();
       }
       final int port = config.getServerPort() + 2 * (index + 1);
       final int dashboardPort = config.getServerDashboardPort()
           + 2 * (index + 1);
       final String scheme = config.isServerSecure() ? "https" : "http";
       waiter = new ShutdownWaiter();
       running = new Thread(new Runnable() {
         @Override
         public void run() {
           try {
             // TODO(ejona): Figure out how much configuration to share.
             int ret = JavaExec.exec(jar, workingDir, Arrays.<String>asList(
                 "-Dserver.port=" + port,
                 "-Dserver.dashboardPort=" + dashboardPort,
                 // TODO(ejona): use same security for child
                 "-Dserver.secure=false",
                 // TODO(ejona): REMOVE THIS HACK. WE NEED TO DO PROPER SECURITY
                 // COMMUNICATION AND HANDLE X-Forwarded-For AND SIMILAR. THIS
                 // DISABLES ALL SECURITY.
                 "-Dserver.fullAccessHosts=127.0.0.1",
                 "-Dgsa.hostname=" + config.getGsaHostname(),
                 "-Dgsa.admin.hostname=" + config.getGsaAdminHostname(),
                 "-Dserver.reverseProxyProtocol=" + scheme,
                 "-Dserver.reverseProxyPort=" + config.getServerPort()));
             if (ret != 0) {
               log.log(Level.WARNING, "Error response code from child: " + ret);
             }
           } catch (IOException ex) {
             // TODO(ejona): add more info as to which one failed.
             log.log(Level.WARNING, "IOException in subprocess", ex);
           } catch (InterruptedException ex) {
             log.log(Level.WARNING, "Forced shutdown of child", ex);
           }
         }
       });
       running.start();

       HttpContext context = server.createContext(
           "/" + name + "/", new ReverseProxyHandler(
               URI.create("http://127.0.0.1:" + port + "/")));
       context.getFilters().add(waiter.filter());

       // TODO(ejona): When you end up visiting the dashboard, it redirects you
       // to its port. It would be nice to fix RedirectHandler to deal with that,
       // although it will require additional config parameters.
       HttpContext dashboardContext = dashboardServer.createContext(
           "/" + name + "/", new ReverseProxyHandler(
               URI.create("http://127.0.0.1:" + dashboardPort + "/")));
       dashboardContext.getFilters().add(waiter.filter());
     }

     private void stop(long time, TimeUnit unit) {
       if (running == null) {
         throw new IllegalStateException();
       }
       server.removeContext("/" + name);
       dashboardServer.removeContext("/" + name);
       try {
         waiter.shutdown(time, unit);
       } catch (InterruptedException ex) {
         Thread.currentThread().interrupt();
       }
       // TODO(ejona): Send graceful shutdown request and join with running
       // thread, only interrupting if it times out.
       running.interrupt();
       try {
         running.join(unit.toMillis(time));
       } catch (InterruptedException ex) {
         Thread.currentThread().interrupt();
       }
       running = null;
     }

     private void uninstall() {
     }
   }

   private class ShutdownHook implements Runnable {
     @Override
     public void run() {
       stop(3, TimeUnit.SECONDS);
     }
   }
 }
	// Copyright 2014 Google Inc. All Rights Reserved.
	//
	// 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 com.google.enterprise.adaptor;

	import com.sun.net.httpserver.HttpContext;
	import com.sun.net.httpserver.HttpServer;

	import java.io.File;
	import java.io.IOException;
	import java.net.URI;
	import java.util.Arrays;
	import java.util.concurrent.ConcurrentHashMap;
	import java.util.concurrent.ConcurrentMap;
	import java.util.concurrent.TimeUnit;
	import java.util.logging.Level;
	import java.util.logging.Logger;

	/**
	* Provides environment for running multiple adaptors on the same port and
	* having each instance be managed.
	*/
	// TODO(ejona): improve locking
	// TODO(ejona): improve shutdown while starting
	// TODO(ejona): improve handling of time limits
	// TODO(ejona): improve state pre-condition checking
	public final class Service {
	private static final Logger log = Logger.getLogger(Service.class.getName());

	private final Config config;
	private final HttpServer server;
	private final HttpServer dashboardServer;
	private final ConcurrentMap<String, Instance> instances
	= new ConcurrentHashMap<String, Instance>();
	private final Thread shutdownHook
	= new Thread(new ShutdownHook(), "service-shutdown");
	private int index;

	private Service(Config config) throws IOException {
	this.config = config;
	this.server = Application.createHttpServer(config);
	this.dashboardServer = Application.createDashboardHttpServer(config);
	}

	public synchronized Instance createInstance(String name, File jar,
	File workingDir) {
	Instance instance = new Instance(name, jar, workingDir, index++);
	if (instances.putIfAbsent(name, instance) != null) {
	throw new IllegalArgumentException("Instance by name already present: "
	+ name);
	}
	instance.install();
	return instance;
	}

	public synchronized void deleteInstance(String name, long time,
	TimeUnit unit) {
	Instance instance = instances.get(name);
	if (instance == null) {
	throw new IllegalArgumentException("No instance with name: " + name);
	}
	instance.stop(time, unit);
	instance.uninstall();
	instances.remove(name, instance);
	}

	public synchronized void start() throws IOException {
	daemonInit();
	// The shutdown hook is purposefully not part of the daemon methods,
	// because it should only be done when running from the command line.
	Runtime.getRuntime().addShutdownHook(shutdownHook);
	daemonStart();
	}

	synchronized void daemonInit() {
	server.start();
	dashboardServer.start();
	}

	synchronized void daemonStart() {
	for (Instance instance : instances.values()) {
	instance.start();
	}
	}

	public synchronized void stop(long time, TimeUnit unit) {
	daemonStop(time, unit);
	daemonDestroy(time, unit);
	try {
	Runtime.getRuntime().removeShutdownHook(shutdownHook);
	} catch (IllegalStateException ex) {
	// Already executing hook.
	}
	}

	synchronized void daemonStop(long time, TimeUnit unit) {
	for (Instance instance : instances.values()) {
	instance.stop(time, unit);
	}
	}

	synchronized void daemonDestroy(long time, TimeUnit unit) {
	Application.httpServerShutdown(server, time, unit);
	Application.httpServerShutdown(dashboardServer, time, unit);
	}

	static Service daemonMain(String[] args) throws IOException {
	Config config = new Config();
	Application.autoConfig(config, args,
	new File(Application.DEFAULT_CONFIG_FILE));
	return new Service(config);
	}

	public static void main(String[] args) throws IOException {
	Service service = daemonMain(args);
	// TODO(ejona): decide if we want the JAR to be relative to the parent
	// process or the child process (right now it is relative to the child).
	service.createInstance("adaptor1", new File("../AdaptorTemplate.jar"),
	new File("adaptor1"));
	service.createInstance("adaptor2", new File("../AdaptorTemplate.jar"),
	new File("adaptor2"));
	service.start();
	}

	/**
	* Maybe use this as an interface to allow disabling/enabling and
	* starting/stopping of particular instances?
	*/
	public final class Instance {
	private final String name;
	private final File jar;
	private final File workingDir;
	private final int index;
	private Thread running;
	private ShutdownWaiter waiter;

	private Instance(String name, File jar, File workingDir, int index) {
	if (name == null) {
	throw new NullPointerException();
	}
	if (name.contains("/") \|\| name.startsWith(".")) {
	// Prevent '.', '..', and things containing '/' from being names.
	throw new IllegalArgumentException(
	"Name must not contain / or start with .");
	}
	if (jar == null) {
	throw new NullPointerException();
	}
	if (index < 0 \|\| index > 10000) {
	throw new IllegalArgumentException("Index too large or small: "
	+ index);
	}
	this.name = name;
	this.jar = jar;
	this.workingDir = workingDir;
	this.index = index;
	}

	private void install() {
	// TODO(ejona): add disable support, where we return Service Unavailable
	// instead of Not Found.
	}

	private void start() {
	if (running != null) {
	throw new IllegalStateException();
	}
	final int port = config.getServerPort() + 2 * (index + 1);
	final int dashboardPort = config.getServerDashboardPort()
	+ 2 * (index + 1);
	final String scheme = config.isServerSecure() ? "https" : "http";
	waiter = new ShutdownWaiter();
	running = new Thread(new Runnable() {
	@Override
	public void run() {
	try {
	// TODO(ejona): Figure out how much configuration to share.
	int ret = JavaExec.exec(jar, workingDir, Arrays.<String>asList(
	"-Dserver.port=" + port,
	"-Dserver.dashboardPort=" + dashboardPort,
	// TODO(ejona): use same security for child
	"-Dserver.secure=false",
	// TODO(ejona): REMOVE THIS HACK. WE NEED TO DO PROPER SECURITY
	// COMMUNICATION AND HANDLE X-Forwarded-For AND SIMILAR. THIS
	// DISABLES ALL SECURITY.
	"-Dserver.fullAccessHosts=127.0.0.1",
	"-Dgsa.hostname=" + config.getGsaHostname(),
	"-Dgsa.admin.hostname=" + config.getGsaAdminHostname(),
	"-Dserver.reverseProxyProtocol=" + scheme,
	"-Dserver.reverseProxyPort=" + config.getServerPort()));
	if (ret != 0) {
	log.log(Level.WARNING, "Error response code from child: " + ret);
	}
	} catch (IOException ex) {
	// TODO(ejona): add more info as to which one failed.
	log.log(Level.WARNING, "IOException in subprocess", ex);
	} catch (InterruptedException ex) {
	log.log(Level.WARNING, "Forced shutdown of child", ex);
	}
	}
	});
	running.start();

	HttpContext context = server.createContext(
	"/" + name + "/", new ReverseProxyHandler(
	URI.create("http://127.0.0.1:" + port + "/")));
	context.getFilters().add(waiter.filter());

	// TODO(ejona): When you end up visiting the dashboard, it redirects you
	// to its port. It would be nice to fix RedirectHandler to deal with that,
	// although it will require additional config parameters.
	HttpContext dashboardContext = dashboardServer.createContext(
	"/" + name + "/", new ReverseProxyHandler(
	URI.create("http://127.0.0.1:" + dashboardPort + "/")));
	dashboardContext.getFilters().add(waiter.filter());
	}

	private void stop(long time, TimeUnit unit) {
	if (running == null) {
	throw new IllegalStateException();
	}
	server.removeContext("/" + name);
	dashboardServer.removeContext("/" + name);
	try {
	waiter.shutdown(time, unit);
	} catch (InterruptedException ex) {
	Thread.currentThread().interrupt();
	}
	// TODO(ejona): Send graceful shutdown request and join with running
	// thread, only interrupting if it times out.
	running.interrupt();
	try {
	running.join(unit.toMillis(time));
	} catch (InterruptedException ex) {
	Thread.currentThread().interrupt();
	}
	running = null;
	}

	private void uninstall() {
	}
	}

	private class ShutdownHook implements Runnable {
	@Override
	public void run() {
	stop(3, TimeUnit.SECONDS);
	}
	}
	}