Springboot+Netty+Websocket实现消息推送实例是怎样的

Springboot+Netty+Websocket实现消息推送实例是怎样的，相信很多没有经验的人对此束手无策，为此本文总结了问题出现的原因和解决方法，通过这篇文章希望你能解决这个问题。

前言

WebSocket 使得客户端和服务器之间的数据交换变得更加简单，允许服务端主动向客户端推送数据。在WebSocket API 中，浏览器和服务器只需要完成一次握手，两者之间就直接可以创建持久性的连接，并进行双向数据传输。

Netty框架的优势

1.API使用简单，开发门槛低;

2.功能强大，预置了多种编解码功能，支持多种主流协议;

3.定制能力强，可以通过ChannelHandler对通信框架进行灵活地扩展;

4.性能高，通过与其他业界主流的NIO框架对比，Netty的综合性能最优;

5.成熟、稳定，Netty修复了已经发现的所有JDK NIO BUG，业务开发人员不需要再为NIO的BUG而烦恼

提示：以下是本篇文章正文内容，下面案例可供参考

一、引入netty依赖

    io.netty    netty-all    4.1.48.Final 

二、使用步骤

1.引入基础配置类

package com.test.netty;  public enum Cmd {  START("000", "連接成功"),  WMESSAGE("001", "消息提醒"),  ;  private String cmd;  private String desc;   Cmd(String cmd, String desc) {   this.cmd = cmd;   this.desc = desc;  }   public String getCmd() {   return cmd;  }   public String getDesc() {   return desc;  } }

2.netty服务启动监听器

package com.test.netty;  import io.netty.bootstrap.ServerBootstrap; import io.netty.channel.ChannelFuture; import io.netty.channel.ChannelOption; import io.netty.channel.EventLoopGroup; import io.netty.channel.nio.NioEventLoopGroup; import io.netty.channel.socket.nio.NioServerSocketChannel; import lombok.extern.slf4j.Slf4j; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.beans.factory.annotation.Value; import org.springframework.boot.ApplicationRunner; import org.springframework.context.annotation.Bean; import org.springframework.stereotype.Component;  /**  * @author test  * 
  * 服務啟動監聽器  **/ @Slf4j @Component public class NettyServer {   @Value("${server.netty.port}")  private int port;   @Autowired  private ServerChannelInitializer serverChannelInitializer;   @Bean  ApplicationRunner nettyRunner() {   return args -> {    //new 一個主線程組    EventLoopGroup bossGroup = new NioEventLoopGroup(1);    //new 一個工作線程組    EventLoopGroup workGroup = new NioEventLoopGroup();    ServerBootstrap bootstrap = new ServerBootstrap()      .group(bossGroup, workGroup)      .channel(NioServerSocketChannel.class)      .childHandler(serverChannelInitializer)      //設置隊列大小      .option(ChannelOption.SO_BACKLOG, 1024)      // 兩小時內沒有數據的通信時,TCP會自動發送一個活動探測數據報文      .childOption(ChannelOption.SO_KEEPALIVE, true);    //綁定端口,開始接收進來的連接    try {     ChannelFuture future = bootstrap.bind(port).sync();     log.info("服務器啟動開始監聽端口: {}", port);     future.channel().closeFuture().sync();    } catch (InterruptedException e) {     e.printStackTrace();    } finally {     //關閉主線程組     bossGroup.shutdownGracefully();     //關閉工作線程組     workGroup.shutdownGracefully();    }   };  } }

3.netty服务端处理器

package com.test.netty;  import com.test.common.util.JsonUtil; import io.netty.channel.Channel; import io.netty.channel.ChannelHandler; import io.netty.channel.ChannelHandlerContext; import io.netty.channel.SimpleChannelInboundHandler; import io.netty.handler.codec.http.websocketx.TextWebSocketFrame; import io.netty.handler.codec.http.websocketx.WebSocketServerProtocolHandler; import lombok.Data; import lombok.extern.slf4j.Slf4j; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Component;  import java.net.URLDecoder; import java.util.*;  /**  * @author test  * 
  * netty服務端處理器  **/ @Slf4j @Component @ChannelHandler.Sharable public class NettyServerHandler extends SimpleChannelInboundHandler {   @Autowired  private ServerChannelCache cache;  private static final String dataKey = "test=";   @Data  public static class ChannelCache {  }    /**   * 客戶端連接會觸發   */  @Override  public void channelActive(ChannelHandlerContext ctx) throws Exception {   Channel channel = ctx.channel();   log.info("通道連接已打開，ID->{}......", channel.id().asLongText());  }   @Override  public void userEventTriggered(ChannelHandlerContext ctx, Object evt) throws Exception {   if (evt instanceof WebSocketServerProtocolHandler.HandshakeComplete) {    Channel channel = ctx.channel();    WebSocketServerProtocolHandler.HandshakeComplete handshakeComplete = (WebSocketServerProtocolHandler.HandshakeComplete) evt;    String requestUri = handshakeComplete.requestUri();    requestUri = URLDecoder.decode(requestUri, "UTF-8");    log.info("HANDSHAKE_COMPLETE，ID->{}，URI->{}", channel.id().asLongText(), requestUri);    String socketKey = requestUri.substring(requestUri.lastIndexOf(dataKey) + dataKey.length());    if (socketKey.length() > 0) {     cache.add(socketKey, channel);     this.send(channel, Cmd.DOWN_START, null);    } else {     channel.disconnect();     ctx.close();    }   }   super.userEventTriggered(ctx, evt);  }   @Override  public void channelInactive(ChannelHandlerContext ctx) throws Exception {   Channel channel = ctx.channel();   log.info("通道連接已斷開，ID->{}，用戶ID->{}......", channel.id().asLongText(), cache.getCacheId(channel));   cache.remove(channel);  }   /**   * 發生異常觸發   */  @Override  public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {   Channel channel = ctx.channel();   log.error("連接出現異常，ID->{}，用戶ID->{}，異常->{}......", channel.id().asLongText(), cache.getCacheId(channel), cause.getMessage(), cause);   cache.remove(channel);   ctx.close();  }   /**   * 客戶端發消息會觸發   */  @Override  protected void channelRead0(ChannelHandlerContext ctx, TextWebSocketFrame msg) throws Exception {   try {    // log.info("接收到客戶端發送的消息：{}", msg.text());    ctx.channel().writeAndFlush(new TextWebSocketFrame(JsonUtil.toString(Collections.singletonMap("cmd", "100"))));   } catch (Exception e) {    log.error("消息處理異常：{}", e.getMessage(), e);   }  }   public void send(Cmd cmd, String id, Object obj) {   HashMap channels = cache.get(id);   if (channels == null) {    return;   }   Map data = new LinkedHashMap<>();   data.put("cmd", cmd.getCmd());   data.put("data", obj);   String msg = JsonUtil.toString(data);   log.info("服務器下發消息: {}", msg);   channels.values().forEach(channel -> {    channel.writeAndFlush(new TextWebSocketFrame(msg));   });  }   public void send(Channel channel, Cmd cmd, Object obj) {   Map data = new LinkedHashMap<>();   data.put("cmd", cmd.getCmd());   data.put("data", obj);   String msg = JsonUtil.toString(data);   log.info("服務器下發消息: {}", msg);   channel.writeAndFlush(new TextWebSocketFrame(msg));  }  }

4.netty服务端缓存类

package com.test.netty;  import io.netty.channel.Channel; import io.netty.util.AttributeKey; import org.springframework.stereotype.Component;  import java.util.HashMap; import java.util.concurrent.ConcurrentHashMap;  @Component public class ServerChannelCache {  private static final ConcurrentHashMap> CACHE_MAP = new ConcurrentHashMap<>();  private static final AttributeKey CHANNEL_ATTR_KEY = AttributeKey.valueOf("test");   public String getCacheId(Channel channel) {   return channel.attr(CHANNEL_ATTR_KEY).get();  }   public void add(String cacheId, Channel channel) {   channel.attr(CHANNEL_ATTR_KEY).set(cacheId);   HashMap hashMap = CACHE_MAP.get(cacheId);   if (hashMap == null) {    hashMap = new HashMap<>();   }   hashMap.put(channel.id().asShortText(), channel);   CACHE_MAP.put(cacheId, hashMap);  }   public HashMap get(String cacheId) {   if (cacheId == null) {    return null;   }   return CACHE_MAP.get(cacheId);  }   public void remove(Channel channel) {   String cacheId = getCacheId(channel);   if (cacheId == null) {    return;   }   HashMap hashMap = CACHE_MAP.get(cacheId);   if (hashMap == null) {    hashMap = new HashMap<>();   }   hashMap.remove(channel.id().asShortText());   CACHE_MAP.put(cacheId, hashMap);  } }

5.netty服务初始化器

package com.test.netty;  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 org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Component;  /**  * @author test  * 
  * netty服務初始化器  **/ @Component public class ServerChannelInitializer extends ChannelInitializer {   @Autowired  private NettyServerHandler nettyServerHandler;   @Override  protected void initChannel(SocketChannel socketChannel) throws Exception {   ChannelPipeline pipeline = socketChannel.pipeline();   pipeline.addLast(new HttpServerCodec());   pipeline.addLast(new ChunkedWriteHandler());   pipeline.addLast(new HttpObjectAggregator(8192));   pipeline.addLast(new WebSocketServerProtocolHandler("/test.io", true, 5000));   pipeline.addLast(nettyServerHandler);  } }

6.html测试

                        
    運行 WebSocket   
      

7.vue测试

mounted() {    this.initWebsocket();   },   methods: {    initWebsocket() {     let websocket = new WebSocket('ws://localhost:port/test.io?test=123456');     websocket.onmessage = (event) => {      let msg = JSON.parse(event.data);      switch (msg.cmd) {       case "000":        this.$message({         type: 'success',         message: "建立實時連接成功！",         duration: 1000        })        setInterval(()=>{websocket.send("heartbeat")},60*1000);        break;       case "001":        this.$message.warning("收到一條新的信息，請及時查看！")        break;      }     }     websocket.onclose = () => {      setTimeout(()=>{       this.initWebsocket();      },30*1000);     }     websocket.onerror = () => {      setTimeout(()=>{       this.initWebsocket();      },30*1000);     }    },   }, ![在這裡插入圖片描述](https://img-blog.csdnimg.cn/20210107160420568.jpg?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3d1X3Fpbmdfc29uZw==,size_16,color_FFFFFF,t_70#pic_center)

8.服务器下发消息

@Autowired  private NettyServerHandler nettyServerHandler; nettyServerHandler.send(CmdWeb.WMESSAGE, id, message);

看完上述内容，你们掌握Springboot+Netty+Websocket实现消息推送实例是怎样的的方法了吗？如果还想学到更多技能或想了解更多相关内容，欢迎关注行业资讯频道，感谢各位的阅读！