Socket.IO Java Server

ScaleCube Socket.IO is a lightweight implementation of Socket.IO Java server based on Netty framework. It implements subset of Socket.IO protocol which is optimized for high throughput and low latency realtime messaging. Supports 0.7+ up to 0.9.16 versions of Socket.IO-client.

Supported transport protocols:

• WebSocket
• Flash Socket
• XHR-Polling
• JSONP-Polling

Performance

Tested on VM: CentOS, 4vCPU, 2GB RAM, Java 7

Client Sessions:

• 10,000 long-polling sessions on single node
• 50,000 WebSocket sessions on single node

TPS:

• 4,000 requests per second per single channel.
• 80,000 requests per second total.

How to use

  SocketIOServer socketIoServer = SocketIOServer.newInstance(5000 /*port*/);
  socketIoServer.setListener(new SocketIOAdapter() {
    public void onMessage(ISession session, ByteBuf message) {
      System.out.println("Received: " + message.toString(CharsetUtil.UTF_8));
      message.release();
    }
  });
  socketIoServer.start();

For more examples, see Socket.IO Examples.

Maven

<dependency>
  <groupId>io.scalecube</groupId>
  <artifactId>socketio</artifactId>
  <version>2.1.0</version>
</dependency>

Starting from version 2.0.1 Netty dependency is optional in order to allow change of Netty version independently. So following dependencies should be added to your project:

<dependency>
  <groupId>io.netty</groupId>
  <artifactId>netty-buffer</artifactId>
  <version>4.0.33.Final</version>
</dependency>
<dependency>
  <groupId>io.netty</groupId>
  <artifactId>netty-common</artifactId>
  <version>4.0.33.Final</version>
</dependency>
<dependency>
  <groupId>io.netty</groupId>
  <artifactId>netty-handler</artifactId>
  <version>4.0.33.Final</version>
</dependency>
<dependency>
  <groupId>io.netty</groupId>
  <artifactId>netty-codec</artifactId>
  <version>4.0.33.Final</version>
</dependency>
<dependency>
  <groupId>io.netty</groupId>
  <artifactId>netty-codec-http</artifactId>
  <version>4.0.33.Final</version>
</dependency>

Maven dependency for versions up to 1.1.2:

<dependency>
	<groupId>com.github.socketIo4Netty</groupId>
	<artifactId>socketIo4Netty</artifactId>
	<version>1.1.2</version>
</dependency>

License

Apache License, Version 2.0