SpringBoot整合WebSocket的客户端和服务端的实现

本文是项目中使用了websocket进行一些数据的推送，对比项目做了一个demo，ws的相关问题不做细数，仅做一下记录。

    此demo针对ws的搭建主要逻辑背景是一个服务端B：通讯层    产生消息推送出去，另外一个项目A充当客户端和服务端，A的客户端:是接收通讯层去无差别接收这些消息，A的服务端:根据地址ip去订阅。用户通过订阅A的ws，同时记录下自己的信息，项目B推送的消息，项目A接收到之后通过当初订阅的逻辑和一些权限过滤条件对项目B产生的消息进行过滤再推送到用户客户端上。

    一、项目中服务端的创建

首先引入maven仓库

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-websocket</artifactId>
        </dependency>

websocket的服务端搭建

 同时注意springboot要开启ws服务

启动类加上@EnableScheduling

简要解读demo

 /webSocket/{id}：链接的id是业务上的一个id，这边之前做过类似拍卖的，相当于一个服务端或者业务上的一个标识，是客户端指明链接到哪一个拍卖间的标识

 @ServerEndpoint：作为服务端的注解。

package com.ghh.myproject.websocket;

import cn.hutool.core.lang.UUID;
import com.alibaba.fastjson.JSON;
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.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;

@ServerEndpoint("/webSocket/{id}")
@Component
public class WebSocket {

    private Logger log = LoggerFactory.getLogger(WebSocket.class);

    private static int onlineCount = 0;
    /** 创建一个map存放   产生的ws链接推送 */
    private static Map<String, WebSocket> clients = new ConcurrentHashMap<>();
    /** 创建一个map存放   当前接入的客户端 */
    private static Map<String, String> idMap = new ConcurrentHashMap<>();
    
    private Session session;
    /** 链接进入的一个场景id */
    private String id;
    /** 每一个链接的一个唯一标识 */
    private String userNo;

    /**
    * @Description: 第三方文接入当前项目websocket后的记录信息
    * @DateTime: 2021/7/5 10:02
    * @Author: GHH
    * @Params: [id, session]
    * @Return void
    */
    @OnOpen
    public void onOpen(@PathParam("id") String id, Session session) throws IOException {
        log.info("已连接到id:{}竞拍场,当前竞拍场人数:{}", id, getUserNosById(id).size());
        this.id = id;
        this.session = session;
        // 生成一个随机序列号来存储一个id下的所有用户
        this.userNo = UUID.fastUUID().toString();
        addOnlineCount();
        //根据随机序列号存储一个socket连接
        clients.put(userNo, this);
        idMap.put(userNo, id);


    }


    /**
    * @Description: 关闭连接
    * @DateTime: 2021/7/5 10:02
    * @Author: GHH
    * @Params: []
    * @Return void
    */
    @OnClose
    public void onClose() throws IOException {
        clients.remove(userNo);
        idMap.remove(userNo);
        subOnlineCount();

    }

    /**
    * @Description: 客户端发送消息调用此方法
    * @DateTime: 2021/6/16 15:35
    * @Author: GHH
    * @Params: [message]
    * @Return void
    */
    @OnMessage
    public void onMessage(String message) throws IOException {
//        JSONObject jsonTo = JSONObject.parseObject(message);
//        String mes = (String) jsonTo.get("message");
//        if (!("All").equals(jsonTo.get("To"))) {
//            sendMessageTo(mes, jsonTo.get("To").toString());
//        } else {
//            sendMessageAll(message);
//        }
        log.info("onMessage方法成功");
    }

    @OnError
    public void onError(Session session, Throwable error) {
        log.error("{}", error);
    }

    public static void sendMessageTo(String message, String userNo) throws IOException {
        // session.getBasicRemote().sendText(message);
        //session.getAsyncRemote().sendText(message);
        WebSocket webSocket = clients.get(userNo);
        if (webSocket != null && webSocket.session.isOpen()) {
            webSocket.session.getAsyncRemote().sendText(JSON.toJSONString(message));
        }

    }


    /**
    * @Description: 推送到指定的id值的记录
    * @DateTime: 2021/6/15 17:11
    * @Author: GHH
    * @Params: [message, id]
    * @Return void
    */
    public static void sendMessageToById(String message, String id) {
        // session.getBasicRemote().sendText(message);
        //session.getAsyncRemote().sendText(message);
        //根据id获取所有的userNo链接的用户
        List<String> userNos = getUserNosById(id);

        for (WebSocket item : clients.values()) {
            //遍历链接的value值，如果当前传入的id中链接的用户包含value值，则推送。
            if (userNos.contains(item.userNo)) {
                item.session.getAsyncRemote().sendText(message);
            }
        }
    }


    /**
    * @Description: 推送所有开启的信息
    * @DateTime: 2021/6/15 17:13
    * @Author: GHH
    * @Params: [message]
    * @Return void
    */
    public static void sendMessageAll(String message){
        for (WebSocket item : clients.values()) {
            item.session.getAsyncRemote().sendText(message);
        }
    }


    public static synchronized int getOnlineCount() {
        return onlineCount;
    }


    public static synchronized void addOnlineCount() {
        WebSocket.onlineCount++;
    }


    public static synchronized void subOnlineCount() {
        WebSocket.onlineCount--;
    }


    public static synchronized Map<String, WebSocket> getClients() {
        return clients;
    }


    /**
    * @Description: 根据相应场景的一些逻辑处理
    * @DateTime: 2021/7/5 10:03
    * @Author: GHH
    * @Params: [id]
    * @Return java.util.List<java.lang.String>
    */
    public static List<String> getUserNosById(String id) {
        ArrayList<String> userNos = new ArrayList<>();

        for (Map.Entry<String, String> entry : idMap.entrySet()) {
            if (entry.getValue().equals(id)) {
                userNos.add(entry.getKey());
            }
        }
        return userNos;
    }

}

　demo中模拟的是定时器推送，第一个参数是消息内容，第二个是推送到哪一个拍卖间或者其他业务上的内容。方法的具体内容上一段代码有详细解释，有通过id，或者发送给全部ws链接的客户端

WebSocket.sendMessageToById(""+count,2+"");

    @Scheduled(cron = "*/5 * * * * ?")
    public void job1(){
        log.info("测试生成次数:{}",count);
        redisTemplate.opsForValue().set("测试"+count, ""+count++);
        if (count%2==0){
            WebSocket.sendMessageToById(""+count,2+"");
        }else {
            WebSocket.sendMessageToById(""+count,1+"");
        }

        log.info("websocket发送"+count);
    }

二、java充当客户端链接ws。

  上述是java作为ws服务端推送当前业务信息的一个demo。我们项目目前做的是一个通讯层的概念，只能够推送数据内容，却无法根据用户权限去推送不同的数据。

   ws客户端的搭建，首先链接ws服务端。首先是我们另外一个服务的ws配置信息，我这边demo是模拟链接上面的ws服务

  1、ws客户端的配置

package com.ghh.websocketRecive.wsMessage;

import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;

import javax.websocket.ContainerProvider;
import javax.websocket.Session;
import javax.websocket.WebSocketContainer;
import java.net.URI;

/**
 * @author ghh
 * @date 2019-08-16 16:02
 */
@Component
@Slf4j
public class WSClient {
    public static Session session;


    public static void startWS() {
        try {
            if (WSClient.session != null) {
                WSClient.session.close();
            }
            WebSocketContainer container = ContainerProvider.getWebSocketContainer();
            //设置消息大小最大为10M
            container.setDefaultMaxBinaryMessageBufferSize(10*1024*1024);
            container.setDefaultMaxTextMessageBufferSize(10*1024*1024);
            // 客户端，开启服务端websocket。
            String uri = "ws://192.168.0.108:8082/webSocket/1";
            Session session = container.connectToServer(WSHandler.class, URI.create(uri));
            WSClient.session = session;
        } catch (Exception ex) {
            log.info(ex.getMessage());
        }
    }
}

   2、配置信息需要在项目启动的时候去启用和链接ws服务

package com.ghh.websocketRecive;


import com.ghh.websocketRecive.wsMessage.WSClient;
import lombok.extern.slf4j.Slf4j;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.scheduling.annotation.EnableScheduling;

import javax.annotation.PostConstruct;

@Slf4j
@EnableScheduling
@SpringBootApplication
@MapperScan("com.ghh.websocketRecive.dao")
public class WebsocketReciveApplication {
    public static void main(String[] args) {
        SpringApplication.run(WebsocketReciveApplication.class, args);
    }

    @PostConstruct
    public void init(){
        log.info("初始化应用程序");
　　　　　// 初始化ws，链接服务端
        WSClient.startWS();
    }
}

  3、接收服务端推送的消息进行权限过滤demo

@ClientEndpoint：作为ws的客户端注解，@OnMessage接收服务端推送的消息。

package com.ghh.websocketRecive.wsMessage;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import com.ghh.websocketRecive.entity.Student;
import com.ghh.websocketRecive.service.UserService;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Component;

import javax.annotation.PostConstruct;
import javax.websocket.*;
import java.util.Objects;
import java.util.Set;

import static com.ghh.websocketRecive.wsMessage.WSClient.startWS;


@ClientEndpoint
@Slf4j
@Component
public class WSHandler {
    @Autowired
    RedisTemplate<String,String> redisTemplate;
    private static RedisTemplate<String,String> redisTemplateService;

    @PostConstruct
    public void init() {
        redisTemplateService=redisTemplate;
    }

    @OnOpen
    public void onOpen(Session session) {
        WSClient.session = session;
    }

    @OnMessage
    public void processMessage(String message) {
        log.info("websocketRecive接收推送消息"+message);
        int permission = Integer.parseInt(message)%5;
        //查询所有订阅的客户端的ip。
        Set<String> keys = redisTemplateService.keys("ip:*");
        for (String key : keys) {
            // 根据登录后存储的客户端ip，获取权限地址
            String s = redisTemplateService.opsForValue().get(key);
            String[] split = s.split(",");
            for (String s1 : split) {
                //向含有推送过来的数据权限地址的客户端推送告警数据。
                if (s1.equals(permission+"")){
                    WebSocket.sendMessageToByIp(message,key.split(":")[1]);
                }
            }
        }
    }

    @OnError
    public void processError(Throwable t) {
        WSClient.session = null;
        try {
            Thread.sleep(5000);
            startWS();
        } catch (InterruptedException e) {
            log.error("---websocket processError InterruptedException---", e);
        }
        log.error("---websocket processError error---", t);
    }

    @OnClose
    public void processClose(Session session, CloseReason closeReason) {
        log.error(session.getId() + closeReason.toString());
    }

    public void send(String sessionId, String message) {
        try {
            log.info("send Msg:" + message);
            if (Objects.nonNull(WSClient.session)) {
                WSClient.session.getBasicRemote().sendText(message);
            } else {
                log.info("---websocket error----");
            }

        } catch (Exception e) {
            log.error("---websocket send error---", e);
        }

    }
}

 4、ws客户端推送消息，推送消息和上面服务端类似。这边是根据ip

package com.ghh.websocketRecive.wsMessage;

import cn.hutool.core.lang.UUID;
import com.alibaba.fastjson.JSON;
import com.ghh.websocketRecive.service.UserService;
import lombok.Builder;
import lombok.Data;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Component;

import javax.annotation.PostConstruct;
import javax.websocket.*;
import javax.websocket.server.PathParam;
import javax.websocket.server.ServerEndpoint;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;

@ServerEndpoint("/webSocket/{ip}")
@Component
public class WebSocket {

    private Logger log = LoggerFactory.getLogger(WebSocket.class);

    private static int onlineCount = 0;

    private static Map<String, WebSocket> clients = new ConcurrentHashMap<>();

    private Session session;
    /** 当前连接服务端的客户端ip */
    private String ip;

    @Autowired
    RedisTemplate<String,String> redisTemplate;
    private static RedisTemplate<String,String> redisTemplateService;
    @PostConstruct
    public void init() {
        redisTemplateService = redisTemplate;
    }


    @OnOpen
    public void onOpen(@PathParam("ip") String ip, Session session) throws IOException {
        log.info("ip:{}客户端已连接:,当前客户端数量:{}", ip, onlineCount+1);
        this.ip = ip;
        this.session = session;
        // 接入一个websocket则生成一个随机序列号
        addOnlineCount();
        //根据随机序列号存储一个socket连接
        clients.put(ip, this);
    }


    @OnClose
    public void onClose() throws IOException {
        clients.remove(ip);
        onlineCount--;
        subOnlineCount();
    }

    /**
    * @Description: 客户端发送消息调用此方法
    * @DateTime: 2021/6/16 15:35
    * @Author: GHH
    * @Params: [message]
    * @Return void
    */
    @OnMessage
    public void onMessage(String message) throws IOException {
        log.info("客户端发送消onMessage方法成功");
    }

    @OnError
    public void onError(Session session, Throwable error) {
        log.error("{}", error);
    }

    public static void sendMessageTo(String message, String userNo) throws IOException {
        WebSocket webSocket = clients.get(userNo);
        if (webSocket != null && webSocket.session.isOpen()) {
            webSocket.session.getAsyncRemote().sendText(JSON.toJSONString(message));
        }
    }

    /**
    * @Description: 推送到指定的ip值的记录
    * @DateTime: 2021/6/15 17:11
    * @Author: GHH
    * @Params: [message, id]
    * @Return void
    */
    public static void sendMessageToByIp(String message, String ip) {
        for (WebSocket item : clients.values()) {
            //遍历链接的value值，如果当前传入的ip中链接的用户包含value值，则推送。
            if (item.ip.equals(ip)) {
                item.session.getAsyncRemote().sendText(message);
            }
        }
    }


    /**
    * @Description: 推送所有开启的信息
    * @DateTime: 2021/6/15 17:13
    * @Author: GHH
    * @Params: [message]
    * @Return void
    */
    public static void sendMessageAll(String message){
        for (WebSocket item : clients.values()) {
            item.session.getAsyncRemote().sendText(message);
        }
    }


    public static synchronized int getOnlineCount() {
        return onlineCount;
    }


    public static synchronized void addOnlineCount() {
        WebSocket.onlineCount++;
    }


    public static synchronized void subOnlineCount() {
        WebSocket.onlineCount--;
    }


    public static synchronized Map<String, WebSocket> getClients() {
        return clients;
    }

}

概述：

    至此，简易的demo搭建完成，项目gitee网址:https://gitee.com/ghhNB/study.git

    如有疑惑部分，欢迎大家积极探讨