基于Websocket协议的IM实战之netty服务端分析

Myth丶恋晨 2023-10-02 19:49 17阅读 0赞

前几篇分析基于http 协议的netty服务端，今天我们基于Websocket协议的IM实战之netty服务端分析，服务端依然用boot服务，同时扫描netty相关启动项，pom引入和yml配置同几篇类似：

1、pom 引入：

<dependency>
                <groupId>io.netty</groupId>
                <artifactId>netty-all</artifactId>
                <version>4.1.50.Final</version>
            </dependency>

2、yml和boot启动类省略，netty核心配置：

import io.netty.bootstrap.ServerBootstrap;
    import io.netty.channel.ChannelFuture;
    import io.netty.channel.EventLoopGroup;
    import io.netty.channel.nio.NioEventLoopGroup;
    import io.netty.channel.socket.nio.NioServerSocketChannel;
    import org.springframework.stereotype.Component;
    @Component
    public class WebSocketServer {
    
        private static class SingletionWSServer {
            static final WebSocketServer instance = new WebSocketServer();
        }
    
        public static WebSocketServer getInstance() {
            return SingletionWSServer.instance;
        }
    
        private EventLoopGroup mainGroup;
        private EventLoopGroup subGroup;
        private ServerBootstrap server;
        private ChannelFuture future;
    
        public WebSocketServer() {
            mainGroup = new NioEventLoopGroup();
            subGroup = new NioEventLoopGroup();
            server = new ServerBootstrap();
            server.group(mainGroup, subGroup)
                    .channel(NioServerSocketChannel.class)
                    .childHandler(new WSServerInitialzer());
        }
    
        public void start() {
            this.future = server.bind("172.17.9.194",8888);
            if (future.isSuccess()) {
                System.out.println("启动 Netty 成功");
            }
        }
    }

3、WSServerInitialzer 类分析：

import io.netty.channel.ChannelInitializer;
    import io.netty.channel.ChannelPipeline;
    import io.netty.channel.socket.SocketChannel;
    import io.netty.handler.codec.http.HttpObjectAggregator;
    import io.netty.handler.codec.http.HttpServerCodec;
    import io.netty.handler.codec.http.websocketx.WebSocketServerProtocolHandler;
    import io.netty.handler.stream.ChunkedWriteHandler;
    import io.netty.handler.timeout.IdleStateHandler;
    
    public class WSServerInitialzer extends ChannelInitializer<SocketChannel> {
        @Override
        protected void initChannel(SocketChannel channel) throws Exception {
            //获取管道（pipeline）
            ChannelPipeline pipeline = channel.pipeline();
            //websocket 基于http协议，所需要的http 编解码器
            pipeline.addLast(new HttpServerCodec());
            //在http上有一些数据流产生，有大有小，我们对其进行处理，既然如此，我们需要使用netty 对下数据流写 提供支持，这个类叫：ChunkedWriteHandler
            pipeline.addLast(new ChunkedWriteHandler());
            //对httpMessage 进行聚合处理，聚合成request或 response
            pipeline.addLast(new HttpObjectAggregator(1024*64));
    
            //================&#