netty 转发服务

NettyServer

package com.youxiong.netty.server;

import com.youxiong.netty.handler.MyChannelHandler;
import io.netty.bootstrap.ServerBootstrap;
import io.netty.channel.*;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.handler.codec.http.HttpObjectAggregator;
import io.netty.handler.codec.http.HttpServerCodec;
import io.netty.handler.stream.ChunkedWriteHandler;
import io.netty.handler.timeout.IdleStateHandler;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;

import javax.annotation.PostConstruct;
import java.util.concurrent.TimeUnit;

@Component
public class NettyServer {

    private static final Logger LOGGER = LoggerFactory.getLogger(NettyServer.class);

    @Value("${netty.server.port}")
    public Integer port;


    public Integer getPort() {
        return port;
    }

    public void setPort(Integer port) {
        this.port = port;
    }

    private void startServer(){
        //服务端需要2个线程组  boss处理客户端连接  work进行客服端连接之后的处理
        EventLoopGroup boss = new NioEventLoopGroup();
        EventLoopGroup work = new NioEventLoopGroup();
        try {
            ServerBootstrap bootstrap = new ServerBootstrap();
            //服务器 配置
            bootstrap.group(boss,work).channel(NioServerSocketChannel.class)
            .childHandler(new ChannelInitializer<SocketChannel>() {
                protected void initChannel(SocketChannel socketChannel) throws Exception {
                    // HttpServerCodec：将请求和应答消息解码为HTTP消息
                    socketChannel.pipeline().addLast("http-codec",new HttpServerCodec());
                    // HttpObjectAggregator：将HTTP消息的多个部分合成一条完整的HTTP消息
                    socketChannel.pipeline().addLast("aggregator",new HttpObjectAggregator(65536));
                    // ChunkedWriteHandler：向客户端发送HTML5文件
                    socketChannel.pipeline().addLast("http-chunked",new ChunkedWriteHandler());
                    // 进行设置心跳检测
                    socketChannel.pipeline().addLast(new IdleStateHandler(60,30,60*30, TimeUnit.SECONDS));
                    // 配置通道处理  来进行业务处理
                    socketChannel.pipeline().addLast(new MyChannelHandler());
                }
            }).option(ChannelOption.SO_BACKLOG,1024).childOption(ChannelOption.SO_KEEPALIVE,true);
            //绑定端口  开启事件驱动
            LOGGER.info("【服务器启动成功========端口："+port+"】");
            Channel channel = bootstrap.bind(port).sync().channel();
            channel.closeFuture().sync();
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            //关闭资源
            boss.shutdownGracefully();
            work.shutdownGracefully();
        }
    }

    @PostConstruct()
    public void init(){
        //需要开启一个新的线程来执行netty server 服务器
        new Thread(new Runnable() {
            public void run() {
                startServer();
            }
        }).start();
    }
}

handler

package com.youxiong.netty.handler;

import com.youxiong.netty.util.GlobalUserUtil;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.*;
import io.netty.handler.codec.http.*;
import io.netty.handler.codec.http.websocketx.*;
import io.netty.handler.timeout.IdleStateEvent;
import io.netty.util.AttributeKey;
import io.netty.util.CharsetUtil;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class MyChannelHandler extends SimpleChannelInboundHandler<Object> {


    private static final Logger LOGGER = LoggerFactory.getLogger(MyChannelHandler.class);

    private static final String URI = "websocket";

    private WebSocketServerHandshaker handshaker ;

    /**
     * 连接上服务器
     * @param ctx
     * @throws Exception
     */
    @Override
    public void handlerAdded(ChannelHandlerContext ctx) throws Exception {
        LOGGER.info("【handlerAdded】====>"+ctx.channel().id());
        GlobalUserUtil.channels.add(ctx.channel());
    }

    /**
     * 断开连接
     * @param ctx
     * @throws Exception
     */
    @Override
    public void handlerRemoved(ChannelHandlerContext ctx) throws Exception {
        LOGGER.info("【handlerRemoved】====>"+ctx.channel().id());
        GlobalUserUtil.channels.remove(ctx);
    }

    /**
     * 连接异常   需要关闭相关资源
     * @param ctx
     * @param cause
     * @throws Exception
     */
    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
        LOGGER.error("【系统异常】======>"+cause.toString());
        ctx.close();
        ctx.channel().close();
    }

    /**
     * 活跃的通道  也可以当作用户连接上客户端进行使用
     * @param ctx
     * @throws Exception
     */
    @Override
    public void channelActive(ChannelHandlerContext ctx) throws Exception {
        LOGGER.info("【channelActive】=====>"+ctx.channel());
    }

    /**
     * 不活跃的通道  就说明用户失去连接
     * @param ctx
     * @throws Exception
     */
    @Override
    public void channelInactive(ChannelHandlerContext ctx) throws Exception {
    }

    /**
     * 这里只要完成 flush
     * @param ctx
     * @throws Exception
     */
    @Override
    public void channelReadComplete(ChannelHandlerContext ctx) throws Exception {
        ctx.flush();
    }

    /**
     * 这里是保持服务器与客户端长连接  进行心跳检测 避免连接断开
     * @param ctx
     * @param evt
     * @throws Exception
     */
    @Override
    public void userEventTriggered(ChannelHandlerContext ctx, Object evt) throws Exception {
        if(evt instanceof IdleStateEvent){
            IdleStateEvent stateEvent = (IdleStateEvent) evt;
            PingWebSocketFrame ping = new PingWebSocketFrame();
            switch (stateEvent.state()){
                //读空闲（服务器端）
                case READER_IDLE:
                    LOGGER.info("【"+ctx.channel().remoteAddress()+"】读空闲（服务器端）");
                    ctx.writeAndFlush(ping);
                    break;
                    //写空闲（客户端）
                case WRITER_IDLE:
                    LOGGER.info("【"+ctx.channel().remoteAddress()+"】写空闲（客户端）");
                    ctx.writeAndFlush(ping);
                    break;
                case ALL_IDLE:
                    LOGGER.info("【"+ctx.channel().remoteAddress()+"】读写空闲");
                    break;
            }
        }
    }

    /**
     * 收发消息处理
     * @param ctx
     * @param msg
     * @throws Exception
     */
    protected void messageReceived(ChannelHandlerContext ctx, Object msg) throws Exception {
        if(msg instanceof HttpRequest){
            doHandlerHttpRequest(ctx,(HttpRequest) msg);
        }else if(msg instanceof WebSocketFrame){
            doHandlerWebSocketFrame(ctx,(WebSocketFrame) msg);
        }
    }

    /**
     * websocket消息处理
     * @param ctx
     * @param msg
     */
    private void doHandlerWebSocketFrame(ChannelHandlerContext ctx, WebSocketFrame msg) {
        //判断msg 是哪一种类型  分别做出不同的反应
        if(msg instanceof CloseWebSocketFrame){
            LOGGER.info("【关闭】");
            handshaker.close(ctx.channel(), (CloseWebSocketFrame) msg);
            return ;
        }
        if(msg instanceof PingWebSocketFrame){
            LOGGER.info("【ping】");
            PongWebSocketFrame pong = new PongWebSocketFrame(msg.content().retain());
            ctx.channel().writeAndFlush(pong);
            return ;
        }
        if(msg instanceof PongWebSocketFrame){
            LOGGER.info("【pong】");
            PingWebSocketFrame ping = new PingWebSocketFrame(msg.content().retain());
            ctx.channel().writeAndFlush(ping);
            return ;
        }
        if(!(msg instanceof TextWebSocketFrame)){
            LOGGER.info("【不支持二进制】");
            throw new UnsupportedOperationException("不支持二进制");
        }
        //可以对消息进行处理
        //群发
        for (Channel channel : GlobalUserUtil.channels) {
            channel.writeAndFlush(new TextWebSocketFrame(((TextWebSocketFrame) msg).text()));
        }

    }


    /**
     * wetsocket第一次连接握手
     * @param ctx
     * @param msg
     */
    private void doHandlerHttpRequest(ChannelHandlerContext ctx, HttpRequest msg) {
        // http 解码失败
        if(!msg.getDecoderResult().isSuccess() || (!"websocket".equals(msg.headers().get("Upgrade")))){
            sendHttpResponse(ctx, (FullHttpRequest) msg,new DefaultFullHttpResponse(HttpVersion.HTTP_1_1,HttpResponseStatus.BAD_REQUEST));
        }
        //可以获取msg的uri来判断
        String uri = msg.getUri();
        if(!uri.substring(1).equals(URI)){
            ctx.close();
        }
        ctx.attr(AttributeKey.valueOf("type")).set(uri);
        //可以通过url获取其他参数
        WebSocketServerHandshakerFactory factory = new WebSocketServerHandshakerFactory(
                "ws://"+msg.headers().get("Host")+"/"+URI+"",null,false
        );
        handshaker = factory.newHandshaker(msg);
        if(handshaker == null){
            WebSocketServerHandshakerFactory.sendUnsupportedWebSocketVersionResponse(ctx.channel());
        }
        //进行连接
        handshaker.handshake(ctx.channel(), (FullHttpRequest) msg);
        //可以做其他处理
    }

    private static void sendHttpResponse(ChannelHandlerContext ctx, FullHttpRequest req, DefaultFullHttpResponse res) {
        // 返回应答给客户端
        if (res.getStatus().code() != 200) {
            ByteBuf buf = Unpooled.copiedBuffer(res.getStatus().toString(), CharsetUtil.UTF_8);
            res.content().writeBytes(buf);
            buf.release();
        }
        // 如果是非Keep-Alive，关闭连接
        ChannelFuture f = ctx.channel().writeAndFlush(res);
        if (!HttpHeaders.isKeepAlive(req) || res.getStatus().code() != 200) {
            f.addListener(ChannelFutureListener.CLOSE);
        }
    }
}
package com.youxiong.netty.util;

import io.netty.channel.group.ChannelGroup;
import io.netty.channel.group.DefaultChannelGroup;
import io.netty.util.concurrent.GlobalEventExecutor;

public class GlobalUserUtil {

    //保存全局的  连接上服务器的客户
    public static ChannelGroup channels = new DefaultChannelGroup(GlobalEventExecutor
            .INSTANCE);
}

NettyServer
package com.youxiong.netty.server;
import com.youxiong.netty.handler.MyChannelHandler;import io.netty.bootstrap.ServerBootstrap;import io.netty.channel.*;import io.netty.channel.nio.NioEventLoopGroup;import io.netty.channel.socket.SocketChannel;import io.netty.channel.socket.nio.NioServerSocketChannel;import io.netty.handler.codec.http.HttpObjectAggregator;import io.netty.handler.codec.http.HttpServerCodec;import io.netty.handler.stream.ChunkedWriteHandler;import io.netty.handler.timeout.IdleStateHandler;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.springframework.beans.factory.annotation.Value;import org.springframework.stereotype.Component;
import javax.annotation.PostConstruct;import java.util.concurrent.TimeUnit;
@Componentpublic class NettyServer {
private static final Logger LOGGER = LoggerFactory.getLogger(NettyServer.class);
@Value("${netty.server.port}") public Integer port;

public Integer getPort() { return port; }
public void setPort(Integer port) { this.port = port; }
private void startServer(){ //服务端需要2个线程组 boss处理客户端连接 work进行客服端连接之后的处理 EventLoopGroup boss = new NioEventLoopGroup(); EventLoopGroup work = new NioEventLoopGroup(); try { ServerBootstrap bootstrap = new ServerBootstrap(); //服务器配置 bootstrap.group(boss,work).channel(NioServerSocketChannel.class) .childHandler(new ChannelInitializer<SocketChannel>() { protected void initChannel(SocketChannel socketChannel) throws Exception { // HttpServerCodec：将请求和应答消息解码为HTTP消息 socketChannel.pipeline().addLast("http-codec",new HttpServerCodec()); // HttpObjectAggregator：将HTTP消息的多个部分合成一条完整的HTTP消息 socketChannel.pipeline().addLast("aggregator",new HttpObjectAggregator(65536)); // ChunkedWriteHandler：向客户端发送HTML5文件 socketChannel.pipeline().addLast("http-chunked",new ChunkedWriteHandler()); // 进行设置心跳检测 socketChannel.pipeline().addLast(new IdleStateHandler(60,30,60*30, TimeUnit.SECONDS)); // 配置通道处理来进行业务处理 socketChannel.pipeline().addLast(new MyChannelHandler()); } }).option(ChannelOption.SO_BACKLOG,1024).childOption(ChannelOption.SO_KEEPALIVE,true); //绑定端口开启事件驱动 LOGGER.info("【服务器启动成功========端口："+port+"】"); Channel channel = bootstrap.bind(port).sync().channel(); channel.closeFuture().sync(); }catch (Exception e){ e.printStackTrace(); }finally { //关闭资源 boss.shutdownGracefully(); work.shutdownGracefully(); } }
@PostConstruct() public void init(){ //需要开启一个新的线程来执行netty server 服务器 new Thread(new Runnable() { public void run() { startServer(); } }).start(); }}handler
package com.youxiong.netty.handler;
import com.youxiong.netty.util.GlobalUserUtil;import io.netty.buffer.ByteBuf;import io.netty.buffer.Unpooled;import io.netty.channel.*;import io.netty.handler.codec.http.*;import io.netty.handler.codec.http.websocketx.*;import io.netty.handler.timeout.IdleStateEvent;import io.netty.util.AttributeKey;import io.netty.util.CharsetUtil;import org.slf4j.Logger;import org.slf4j.LoggerFactory;
public class MyChannelHandler extends SimpleChannelInboundHandler<Object> {

private static final Logger LOGGER = LoggerFactory.getLogger(MyChannelHandler.class);
private static final String URI = "websocket";
private WebSocketServerHandshaker handshaker ;
/** * 连接上服务器 * @param ctx * @throws Exception */ @Override public void handlerAdded(ChannelHandlerContext ctx) throws Exception { LOGGER.info("【handlerAdded】====>"+ctx.channel().id()); GlobalUserUtil.channels.add(ctx.channel()); }
/** * 断开连接 * @param ctx * @throws Exception */ @Override public void handlerRemoved(ChannelHandlerContext ctx) throws Exception { LOGGER.info("【handlerRemoved】====>"+ctx.channel().id()); GlobalUserUtil.channels.remove(ctx); }
/** * 连接异常需要关闭相关资源 * @param ctx * @param cause * @throws Exception */ @Override public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception { LOGGER.error("【系统异常】======>"+cause.toString()); ctx.close(); ctx.channel().close(); }
/** * 活跃的通道也可以当作用户连接上客户端进行使用 * @param ctx * @throws Exception */ @Override public void channelActive(ChannelHandlerContext ctx) throws Exception { LOGGER.info("【channelActive】=====>"+ctx.channel()); }
/** * 不活跃的通道就说明用户失去连接 * @param ctx * @throws Exception */ @Override public void channelInactive(ChannelHandlerContext ctx) throws Exception { }
/** * 这里只要完成 flush * @param ctx * @throws Exception */ @Override public void channelReadComplete(ChannelHandlerContext ctx) throws Exception { ctx.flush(); }
/** * 这里是保持服务器与客户端长连接进行心跳检测避免连接断开 * @param ctx * @param evt * @throws Exception */ @Override public void userEventTriggered(ChannelHandlerContext ctx, Object evt) throws Exception { if(evt instanceof IdleStateEvent){ IdleStateEvent stateEvent = (IdleStateEvent) evt; PingWebSocketFrame ping = new PingWebSocketFrame(); switch (stateEvent.state()){ //读空闲（服务器端） case READER_IDLE: LOGGER.info("【"+ctx.channel().remoteAddress()+"】读空闲（服务器端）"); ctx.writeAndFlush(ping); break; //写空闲（客户端） case WRITER_IDLE: LOGGER.info("【"+ctx.channel().remoteAddress()+"】写空闲（客户端）"); ctx.writeAndFlush(ping); break; case ALL_IDLE: LOGGER.info("【"+ctx.channel().remoteAddress()+"】读写空闲"); break; } } }
/** * 收发消息处理 * @param ctx * @param msg * @throws Exception */ protected void messageReceived(ChannelHandlerContext ctx, Object msg) throws Exception { if(msg instanceof HttpRequest){ doHandlerHttpRequest(ctx,(HttpRequest) msg); }else if(msg instanceof WebSocketFrame){ doHandlerWebSocketFrame(ctx,(WebSocketFrame) msg); } }
/** * websocket消息处理 * @param ctx * @param msg */ private void doHandlerWebSocketFrame(ChannelHandlerContext ctx, WebSocketFrame msg) { //判断msg 是哪一种类型分别做出不同的反应 if(msg instanceof CloseWebSocketFrame){ LOGGER.info("【关闭】"); handshaker.close(ctx.channel(), (CloseWebSocketFrame) msg); return ; } if(msg instanceof PingWebSocketFrame){ LOGGER.info("【ping】"); PongWebSocketFrame pong = new PongWebSocketFrame(msg.content().retain()); ctx.channel().writeAndFlush(pong); return ; } if(msg instanceof PongWebSocketFrame){ LOGGER.info("【pong】"); PingWebSocketFrame ping = new PingWebSocketFrame(msg.content().retain()); ctx.channel().writeAndFlush(ping); return ; } if(!(msg instanceof TextWebSocketFrame)){ LOGGER.info("【不支持二进制】"); throw new UnsupportedOperationException("不支持二进制"); } //可以对消息进行处理 //群发 for (Channel channel : GlobalUserUtil.channels) { channel.writeAndFlush(new TextWebSocketFrame(((TextWebSocketFrame) msg).text())); }
}

/** * wetsocket第一次连接握手 * @param ctx * @param msg */ private void doHandlerHttpRequest(ChannelHandlerContext ctx, HttpRequest msg) { // http 解码失败 if(!msg.getDecoderResult().isSuccess() || (!"websocket".equals(msg.headers().get("Upgrade")))){ sendHttpResponse(ctx, (FullHttpRequest) msg,new DefaultFullHttpResponse(HttpVersion.HTTP_1_1,HttpResponseStatus.BAD_REQUEST)); } //可以获取msg的uri来判断 String uri = msg.getUri(); if(!uri.substring(1).equals(URI)){ ctx.close(); } ctx.attr(AttributeKey.valueOf("type")).set(uri); //可以通过url获取其他参数 WebSocketServerHandshakerFactory factory = new WebSocketServerHandshakerFactory( "ws://"+msg.headers().get("Host")+"/"+URI+"",null,false ); handshaker = factory.newHandshaker(msg); if(handshaker == null){ WebSocketServerHandshakerFactory.sendUnsupportedWebSocketVersionResponse(ctx.channel()); } //进行连接 handshaker.handshake(ctx.channel(), (FullHttpRequest) msg); //可以做其他处理 }
private static void sendHttpResponse(ChannelHandlerContext ctx, FullHttpRequest req, DefaultFullHttpResponse res) { // 返回应答给客户端 if (res.getStatus().code() != 200) { ByteBuf buf = Unpooled.copiedBuffer(res.getStatus().toString(), CharsetUtil.UTF_8); res.content().writeBytes(buf); buf.release(); } // 如果是非Keep-Alive，关闭连接 ChannelFuture f = ctx.channel().writeAndFlush(res); if (!HttpHeaders.isKeepAlive(req) || res.getStatus().code() != 200) { f.addListener(ChannelFutureListener.CLOSE); } }}package com.youxiong.netty.util;
import io.netty.channel.group.ChannelGroup;import io.netty.channel.group.DefaultChannelGroup;import io.netty.util.concurrent.GlobalEventExecutor;
public class GlobalUserUtil {
//保存全局的连接上服务器的客户 public static ChannelGroup channels = new DefaultChannelGroup(GlobalEventExecutor .INSTANCE);}--------------------- 作者：yx726843014 来源：CSDN 原文：https://blog.csdn.net/xieliaowa9231/article/details/80151446 版权声明：本文为博主原创文章，转载请附上博文链接！