目录
需求背景websocket协议stomp协议需求背景
闲话不扯，直奔主题。需要和web前端建立长链接，互相实时通讯，因此想到了websocket，后面随着需求的变更，需要用户订阅主题，实现消息的精准推送，发布订阅等，则想到了STOMP(Simple Text-Orientated Messaging Protocol) 面向消息的简单文本协议。
websocket协议
想到了之前写的一个websocket长链接的demo，也贴上代码供大家参考。
pom文件
直接引入spring-boot-starter-websocket即可。
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-websocket</artifactId>
</dependency>
声明websocket endpoint
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.socket.server.standard.ServerEndpointExporter;
/**
* @ClassName WebSocketConfig
* @Author scott
* @Date 2021/6/16
* @Version V1.0
**/
@Configuration
public class WebSocketConfig {
/**
* 注入一个ServerEndpointExporter,该Bean会自动注册使用@ServerEndpoint注解申明的websocket endpoint
*/
@Bean
public ServerEndpointExporter serverEndpointExporter() {
return new ServerEndpointExporter();
}
}
websocket实现类，其中通过注解监听了各种事件，实现了推送消息等相关逻辑
import com.google.common.cache.Cache;
import com.google.common.cache.CacheBuilder;
import com.ruoyi.common.core.domain.AjaxResult;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;
import javax.websocket.*;
import javax.websocket.server.PathParam;
import javax.websocket.server.ServerEndpoint;
import java.util.Objects;
import java.util.Set;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;
/**
* @ClassName: DataTypePushWebSocket
* @Author: scott
* @Date: 2021/6/16
**/
@ServerEndpoint(value = "/ws/dataType/push/{token}")
@Component
public class DataTypePushWebSocket {
private static final Logger log = LoggerFactory.getLogger(DataTypePushWebSocket.class);
/**
* 记录当前在线连接数
*/
private static AtomicInteger onlineCount = new AtomicInteger(0);
private static Cache<String, Session> SESSION_CACHE = CacheBuilder.newBuilder()
.initialCapacity(10)
.maximumSize(300)
.expireAfterWrite(10, TimeUnit.MINUTES)
.build();
/**
* 连接建立成功调用的方法
*/
@OnOpen
public void onOpen(Session session, @PathParam("token")String token) {
String sessionId = session.getId();
onlineCount.incrementAndGet(); // 在线数加1
this.sendMessage("sessionId:" + sessionId +",已经和server建立连接", session);
SESSION_CACHE.put(sessionId,session);
log.info("有新连接加入：{}，当前在线连接数为：{}", session.getId(), onlineCount.get());
}
/**
* 连接关闭调用的方法
*/
@OnClose
public void onClose(Session session,@PathParam("token")String token) {
onlineCount.decrementAndGet(); // 在线数减1
SESSION_CACHE.invalidate(session.getId());
log.info("有一连接关闭：{}，当前在线连接数为：{}", session.getId(), onlineCount.get());
}
/**
* 收到客户端消息后调用的方法
*
* @param message 客户端发送过来的消息
*/
@OnMessage
public void onMessage(String message, Session session,@PathParam("token")String token) {
log.info("服务端收到客户端[{}]的消息:{}", session.getId(), message);
this.sendMessage("服务端已收到推送消息:" + message, session);
}
@OnError
public void onError(Session session, Throwable error) {
log.error("发生错误");
error.printStackTrace();
}
/**
* 服务端发送消息给客户端
*/
private static void sendMessage(String message, Session toSession) {
try {
log.info("服务端给客户端[{}]发送消息{}", toSession.getId(), message);
toSession.getBasicRemote().sendText(message);
} catch (Exception e) {
log.error("服务端发送消息给客户端失败：{}", e);
}
}
public static AjaxResult sendMessage(String message, String sessionId){
Session session = SESSION_CACHE.getIfPresent(sessionId);
if(Objects.isNull(session)){
return AjaxResult.error("token已失效");
}
sendMessage(message,session);
return AjaxResult.success();
}
public static AjaxResult sendBroadcast(String message){
long size = SESSION_CACHE.size();
if(size <=0){
return AjaxResult.error("当前没有在线客户端，无法推送消息");
}
ConcurrentMap<String, Session> sessionConcurrentMap = SESSION_CACHE.asMap();
Set<String> keys = sessionConcurrentMap.keySet();
for (String key : keys) {
Session session = SESSION_CACHE.getIfPresent(key);
DataTypePushWebSocket.sendMessage(message,session);
}
return AjaxResult.success();
}
}
至此websocket服务端代码已经完成。
stomp协议
前端代码.这个是在某个vue工程中写的js，各位大佬自己动手改改即可。其中Settings.wsPath是后端定义的ws地址例如ws://localhost:9003/ws
import Stomp from 'stompjs'
import Settings from '@/settings.js'
export default {
// 是否启用日志 默认启用
debug:true,
// 客户端连接信息
stompClient:{},
// 初始化
init(callBack){
this.stompClient = Stomp.client(Settings.wsPath)
this.stompClient.hasDebug = this.debug
this.stompClient.connect({},suce =>{
this.console("连接成功,信息如下 ↓")
this.console(this.stompClient)
if(callBack){
callBack()
}
},err => {
if(err) {
this.console("连接失败,信息如下 ↓")
this.console(err)
}
})
},
// 订阅
sub(address,callBack){
if(!this.stompClient.connected){
this.console("没有连接,无法订阅")
return
}
// 生成 id
let timestamp= new Date().getTime() + address
this.console("订阅成功 -> "+address)
this.stompClient.subscribe(address,message => {
this.console(address+" 订阅消息通知,信息如下 ↓")
this.console(message)
let data = message.body
callBack(data)
},{
id: timestamp
})
},
unSub(address){
if(!this.stompClient.connected){
this.console("没有连接,无法取消订阅 -> "+address)
return
}
let id = ""
for(let item in this.stompClient.subscriptions){
if(item.endsWith(address)){
id = item
break
}
}
this.stompClient.unsubscribe(id)
this.console("取消订阅成功 -> id:"+ id + " address:"+address)
},
// 断开连接
disconnect(callBack){
if(!this.stompClient.connected){
this.console("没有连接,无法断开连接")
return
}
this.stompClient.disconnect(() =>{
console.log("断开成功")
if(callBack){
callBack()
}
})
},
// 单位 秒
reconnect(time){
setInterval(() =>{
if(!this.stompClient.connected){
this.console("重新连接中...")
this.init()
}
},time * 1000)
},
console(msg){
if(this.debug){
console.log(msg)
}
},
// 向订阅发送消息
send(address,msg) {
this.stompClient.send(address,{},msg)
}
}
后端stomp config,里面都有注释，写的很详细,并且我加入了和前端的心跳ping pong。
package com.cn.scott.config;
import org.springframework.context.annotation.Configuration;
import org.springframework.messaging.simp.config.MessageBrokerRegistry;
import org.springframework.scheduling.concurrent.ThreadPoolTaskScheduler;
import org.springframework.web.socket.config.annotation.EnableWebSocketMessageBroker;
import org.springframework.web.socket.config.annotation.StompEndpointRegistry;
import org.springframework.web.socket.config.annotation.WebSocketMessageBrokerConfigurer;
/**
* @ClassName: WebSocketStompConfig
* @Author: scott
* @Date: 2021/7/8
**/
@Configuration
@EnableWebSocketMessageBroker
public class WebSocketStompConfig implements WebSocketMessageBrokerConfigurer {
private static long HEART_BEAT=10000;
@Override
public void registerStompEndpoints(StompEndpointRegistry registry) {
//允许使用socketJs方式访问，访问点为webSocket，允许跨域
//在网页上我们就可以通过这个链接
//ws://127.0.0.1:port/ws来和服务器的WebSocket连接
registry.addEndpoint("/ws").setAllowedOrigins("*");
}
@Override
public void configureMessageBroker(MessageBrokerRegistry registry) {
ThreadPoolTaskScheduler te = new ThreadPoolTaskScheduler();
te.setPoolSize(1);
te.setThreadNamePrefix("wss-heartbeat-thread-");
te.initialize();
//基于内存的STOMP消息代理来代替mq的消息代理
//订阅Broker名称,/user代表点对点即发指定用户，/topic代表发布广播即群发
//setHeartbeatValue 设置心跳及心跳时间
registry.enableSimpleBroker("/user", "/topic").setHeartbeatValue(new long[]{HEART_BEAT,HEART_BEAT}).setTaskScheduler(te);
//点对点使用的订阅前缀，不设置的话，默认也是/user/
registry.setUserDestinationPrefix("/user/");
}
}
后端stomp协议接受、订阅等动作通知
package com.cn.scott.ws;
import com.alibaba.fastjson.JSON;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.messaging.handler.annotation.DestinationVariable;
import org.springframework.messaging.handler.annotation.MessageMapping;
import org.springframework.messaging.simp.SimpMessagingTemplate;
import org.springframework.messaging.simp.annotation.SubscribeMapping;
import org.springframework.web.bind.annotation.RestController;
/**
* @ClassName StompSocketHandler
* @Author scott
* @Date 2021/6/30
* @Version V1.0
**/
@RestController
public class StompSocketHandler {
@Autowired
private SimpMessagingTemplate simpMessagingTemplate;
/**
* @MethodName: subscribeMapping
* @Description: 订阅成功通知
* @Param: [id]
* @Return: void
* @Author: scott
* @Date: 2021/6/30
**/
@SubscribeMapping("/user/{id}/listener")
public void subscribeMapping(@DestinationVariable("id") final long id) {
System.out.println(">>>>>>用户:"+id +",已订阅");
SubscribeMsg param = new SubscribeMsg(id,String.format("用户【%s】已订阅成功", id));
sendToUser(param);
}
/**
* @MethodName: test
* @Description: 接收订阅topic消息
* @Param: [id, msg]
* @Return: void
* @Author: scott
* @Date: 2021/6/30
**/
@MessageMapping(value = "/user/{id}/listener")
public void UserSubListener(@DestinationVariable long id, String msg) {
System.out.println("收到客户端:" +id+",的消息");
SubscribeMsg param = new SubscribeMsg(id,String.format("已收到用户【%s】发送消息【%s】", id,msg));
sendToUser(param);
}
@GetMapping("/refresh/{userId}")
public void refresh(@PathVariable Long userId, String msg) {
StompSocketHandler.SubscribeMsg param = new StompSocketHandler.SubscribeMsg(userId,String.format("服务端向用户【%s】发送消息【%s】", userId,msg));
sendToUser(param);
}
/**
* @MethodName: sendToUser
* @Description: 推送消息给订阅用户
* @Param: [userId]
* @Return: void
* @Author: scott
* @Date: 2021/6/30
**/
public void sendToUser(SubscribeMsg screenChangeMsg){
//这里可以控制权限等。。。
simpMessagingTemplate.convertAndSendToUser(screenChangeMsg.getUserId().toString(),"/listener", JSON.toJSONString(screenChangeMsg));
}
/**
* @MethodName: sendBroadCast
* @Description: 发送广播，需要用户事先订阅广播
* @Param: [topic, msg]
* @Return: void
* @Author: scott
* @Date: 2021/6/30
**/
public void sendBroadCast(String topic,String msg){
simpMessagingTemplate.convertAndSend(topic,msg);
}
/**
* @ClassName: SubMsg
* @Author: scott
* @Date: 2021/6/30
**/
public static class SubscribeMsg {
private Long userId;
private String msg;
public SubscribeMsg(Long UserId, String msg){
this.userId = UserId;
this.msg = msg;
}
public Long getUserId() {
return userId;
}
public String getMsg() {
return msg;
}
}
}
连接展示
建立连接成功，这里可以看出是基于websocket协议
连接信息
ping pong
调用接口向订阅用户1发送消息,http://localhost:9003/refresh/1?msg=HelloStomp,可以在客户端控制台查看已经收到了消息。这个时候不同用户通过自己的userId可以区分订阅的主题，可以做到通过userId精准的往客户端推送消息。
还记得我们在后端配置的时候还指定了广播的订阅主题/topic，这时我们前端通过js只要订阅了这个主题，那么后端在像这个主题推送消息时，所有订阅的客户端都能收到，感兴趣的小伙伴可以自己试试，api我都写好了。
至此，实战完毕，喜欢的小伙伴麻烦关注加点赞。
springboot + stomp后端源码地址:https://gitee.com/ErGouGeSiBaKe/stomp-server
