WebSocket with Grizzly, OSGi and iPOJO

Setup

In this project we use the Grizzly http-service bundle version 2.2.18 which supports websocket and iPOJO.

    org.glassfish.grizzly.osgi
    grizzly-httpservice-bundle
    2.2.18

    org.apache.felix
    org.apache.felix.ipojo.annotations
    1.6.4

We have to activate the websockets support by settings the following framework properties: 

org.osgi.service.http.port=8080
org.glassfish.grizzly.websocketsSupport=true

A simple 'echo' WebSocketApplication

The following class implements a simple echo websocket app, such as describe here.

import org.glassfish.grizzly.websockets.WebSocket;
import org.glassfish.grizzly.websockets.WebSocketApplication;
 
package org.barjo.websocket.test;
  
public class MyEchoWebSocketApp extends WebSocketApplication {
    
  @Override
  public boolean isApplicationRequest(HttpRequestPacket request) { 
     return true;
  }

  @Override 
  public void onMessage(WebSocket socket,String text) { 
    socket.send(text); //Echo
  }
}

The meat

We create a simple iPOJO component that use the grizzly websocket engine in order to register MyEchoWebSocketApp. Since the WebSocketEngine.getEngine() is static, we don't need to require the HttpService provided by grizlly. This requirement is only here to couple the WebSocketComp lifecycle with the grizzly lifecycle.

    import org.apache.felix.ipojo.annotations.*;
    import org.glassfish.grizzly.websockets.WebSocketApplication;
    import org.glassfish.grizzly.websockets.WebSocketEngine;

    package org.barjo.websocket.test;

    @Component(name="WebSocketComp")
    @Instantiate
    public class WebSocketComp {

        @Requires(optional = true)
        private LogService logger;

        @Requires
        private HttpService http;

        private final WebSocketApplication app;

        public WebSocketComp(BundleContext context){
            app=new MyEchoWebSocketApp();
        }


        /**
         * Start the component, register the app.
         */
        @Validate
        private void start(){
            logger.log(LogService.LOG_INFO,"MyEchoWebSocketApp starting.");
            WebSocketEngine.getEngine().register(app);
        }

        /**
         * Stop the Component, unregister the app.
         */
        @Invalidate
        private void stop(){
            logger.log(LogService.LOG_INFO,"MyEchoWebSocketApp stopping.");
            WebSocketEngine.getEngine().unregister(app);
        }
    }

The test

You can now test our simple echo application on http://www.websocket.org/echo.html, with the websocket ws://localhost:8080 .