Springboot+Netty+Websocket實現訊息推送例項
阿新 • • 發佈：2021-01-17
技術標籤：springboot netty websocketwebsocketnettysocketspring bootjava
Springboot+Netty+Websocket實現訊息推送
文章目錄
前言
WebSocket 使得客戶端和伺服器之間的資料交換變得更加簡單，允許服務端主動向客戶端推送資料。在 WebSocket API 中，瀏覽器和伺服器只需要完成一次握手，兩者之間就直接可以建立永續性的連線，並進行雙向資料傳輸。Netty框架的優勢
1. API使用簡單，開發門檻低；
2. 功能強大，預置了多種編解碼功能，支援多種主流協議；
3. 定製能力強，可以通過ChannelHandler對通訊框架進行靈活地擴充套件；
4. 效能高，通過與其他業界主流的NIO框架對比，Netty的綜合性能最優；
5. 成熟、穩定，Netty修復了已經發現的所有JDK NIO BUG，業務開發人員不需要再為NIO的BUG而煩惱
提示：以下是本篇文章正文內容，下面案例可供參考
一、引入netty依賴
<dependency> <groupId>io.netty</groupId> <artifactId>netty-all</artifactId> <version>4.1.48.Final</version> </dependency>
二、使用步驟
1.引入基礎配置類
package com.test.netty;
public enum Cmd {
START("000", "連線成功"),
WMESSAGE("001", "訊息提醒"),
;
private String cmd;
private String desc;
Cmd(String cmd, String desc) {
this.cmd = cmd;
this.desc = desc;
}
public String getCmd 2.netty服務啟動監聽器
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
* <p>
* 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 一個主執行緒組
EventLoopGroup bossGroup = new NioEventLoopGroup(1);
//new 一個工作執行緒組
EventLoopGroup workGroup = new NioEventLoopGroup();
ServerBootstrap bootstrap = new ServerBootstrap()
.group(bossGroup, workGroup)
.channel(NioServerSocketChannel.class)
.childHandler(serverChannelInitializer)
//設定佇列大小
.option(ChannelOption.SO_BACKLOG, 1024)
// 兩小時內沒有資料的通訊時,TCP會自動傳送一個活動探測資料報文
.childOption(ChannelOption.SO_KEEPALIVE, true);
//繫結埠,開始接收進來的連線
try {
ChannelFuture future = bootstrap.bind(port).sync();
log.info("伺服器啟動開始監聽埠: {}", port);
future.channel().closeFuture().sync();
} catch (InterruptedException e) {
e.printStackTrace();
} finally {
//關閉主執行緒組
bossGroup.shutdownGracefully();
//關閉工作執行緒組
workGroup.shutdownGracefully();
}
};
}
}
3.netty服務端處理器
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
* <p>
* netty服務端處理器
**/
@Slf4j
@Component
@ChannelHandler.Sharable
public class NettyServerHandler extends SimpleChannelInboundHandler<TextWebSocketFrame> {
@Autowired
private ServerChannelCache cache;
private static final String dataKey = "test=";
@Data
public static class ChannelCache {
}
/**
* 客戶端連線會觸發
*/
@Override
public void channelActive(ChannelHandlerContext ctx) throws Exception {
Channel channel = ctx.channel();
log.info("通道連線已開啟，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("通道連線已斷開，ID->{}，使用者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->{}，使用者ID->{}，異常->{}......", channel.id().asLongText(), cache.getCacheId(channel), cause.getMessage(), cause);
cache.remove(channel);
ctx.close();
}
/**
* 客戶端發訊息會觸發
*/
@Override
protected void channelRead0(ChannelHandlerContext ctx, TextWebSocketFrame msg) throws Exception {
try {
// log.info("接收到客戶端傳送的訊息：{}", msg.text());
ctx.channel().writeAndFlush(new TextWebSocketFrame(JsonUtil.toString(Collections.singletonMap("cmd", "100"))));
} catch (Exception e) {
log.error("訊息處理異常：{}", e.getMessage(), e);
}
}
public void send(Cmd cmd, String id, Object obj) {
HashMap<String, Channel> channels = cache.get(id);
if (channels == null) {
return;
}
Map<String, Object> data = new LinkedHashMap<>();
data.put("cmd", cmd.getCmd());
data.put("data", obj);
String msg = JsonUtil.toString(data);
log.info("伺服器下發訊息: {}", msg);
channels.values().forEach(channel -> {
channel.writeAndFlush(new TextWebSocketFrame(msg));
});
}
public void send(Channel channel, Cmd cmd, Object obj) {
Map<String, Object> data = new LinkedHashMap<>();
data.put("cmd", cmd.getCmd());
data.put("data", obj);
String msg = JsonUtil.toString(data);
log.info("伺服器下發訊息: {}", msg);
channel.writeAndFlush(new TextWebSocketFrame(msg));
}
}
4.netty服務端快取類
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<String, HashMap<String, Channel>> CACHE_MAP = new ConcurrentHashMap<>();
private static final AttributeKey<String> 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<String, Channel> hashMap = CACHE_MAP.get(cacheId);
if (hashMap == null) {
hashMap = new HashMap<>();
}
hashMap.put(channel.id().asShortText(), channel);
CACHE_MAP.put(cacheId, hashMap);
}
public HashMap<String, Channel> 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<String, Channel> hashMap = CACHE_MAP.get(cacheId);
if (hashMap == null) {
hashMap = new HashMap<>();
}
hashMap.remove(channel.id().asShortText());
CACHE_MAP.put(cacheId, hashMap);
}
}
5.netty服務初始化器
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 Gjing
* <p>
* netty服務初始化器
**/
@Component
public class ServerChannelInitializer extends ChannelInitializer<SocketChannel> {
@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測試
<!DOCTYPE HTML>
<html>
<head>
<meta charset="utf-8">
<title>test</title>
<script type="text/javascript">
function WebSocketTest()
{
if ("WebSocket" in window)
{
alert("您的瀏覽器支援 WebSocket!");
// 開啟一個 web socket
var ws = new WebSocket("ws://localhost:port/test.io");
ws.onopen = function()
{
// Web Socket 已連線上，使用 send() 方法傳送資料
ws.send("傳送資料");
alert("資料傳送中...");
};
ws.onmessage = function (evt)
{
var received_msg = evt.data;
alert("資料已接收...");
};
ws.onclose = function()
{
// 關閉 websocket
alert("連線已關閉...");
};
}
else
{
// 瀏覽器不支援 WebSocket
alert("您的瀏覽器不支援 WebSocket!");
}
}
</script>
</head>
<body>
<div id="sse">
<a href="javascript:WebSocketTest()">執行 WebSocket</a>
</div>
</body>
</html>
7.vue測試
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: "建立實時連線成功！",
duration: 1000
})
setInterval(()=>{websocket.send("heartbeat")},60*1000);
break;
case "001":
this.$message.warning("收到一條新的資訊，請及時檢視！")
break;
}
}
websocket.onclose = () => {
setTimeout(()=>{
this.initWebsocket();
},30*1000);
}
websocket.onerror = () => {
setTimeout(()=>{
this.initWebsocket();
},30*1000);
}
},
},
8.伺服器下發訊息
@Autowired
private NettyServerHandler nettyServerHandler;
nettyServerHandler.send(CmdWeb.WMESSAGE, id, message);
總結
按照上面步驟，一步一步的來，是可以實現訊息推送的功能的。不要著急，當你除錯成功之後，發現並沒有自己想想中的那麼難，加油！親測可以使用，如果感覺本文件對您有幫助，可以請喝個下午茶！