websocket实现二维码扫描

后端代码

依赖

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

配置类

@Configuration
public class WebSocketConfig {

    /**
     * 注入ServerEndpointExporter，
     * 这个bean会自动注册使用了@ServerEndpoint注解声明的Websocket endpoint
     */
    @Bean
    public ServerEndpointExporter serverEndpointExporter() {
        return new ServerEndpointExporter();
    }
}

处理层

1、可以把@ServerEndpoint理解成@Controller； 2、权限部分记得要处理好，我这里为了省事，在权限部分直接配置了白名单；

@ServerEndpoint(value = "/websocket/{shopId}")
@Component
public class WebSocketServer {

    private Session session;

    private static CopyOnWriteArraySet<WebSocketServer> webSockets =new CopyOnWriteArraySet<>();
    private static Map<String,Session> sessionPool = new HashMap<>();


    @OnOpen
    public void onOpen(Session session, @PathParam(value="shopId")String shopId) {
        this.session = session;
        webSockets.add(this);
        sessionPool.put(shopId, session);
        System.out.println("【websocket消息】有新的连接，总数为:"+webSockets.size());
    }

    @OnClose
    public void onClose() {
        webSockets.remove(this);
        System.out.println("【websocket消息】连接断开，总数为:"+webSockets.size());
    }

    @OnMessage
    public void onMessage(String message) {
        System.out.println("【websocket消息】收到客户端消息:"+message);
    }

    // 此为广播消息
    public void sendAllMessage(String message) {
        for(WebSocketServer webSocket : webSockets) {
            System.out.println("【websocket消息】广播消息:"+message);
            try {
                webSocket.session.getAsyncRemote().sendText(message);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }

    // 此为单点消息
    public void sendOneMessage(String shopId, String message) {
        Session session = sessionPool.get(shopId);
        if (session != null) {
            try {
                session.getAsyncRemote().sendText(message);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }
}

前端代码

<template>
  <el-container style="height: 100%">
          <div class="qrcode" ref="qrCodeUrl"></div>
  </el-container>
</template>

<script>
  import QRCode from 'qrcodejs2'
  export default {
    name: "",
    data() {
      return {
        deliveryCode:null,
        qrcode:null,
        websock: null,
      };
    },
    //加载后运行
    created(){
      this.deliveryCode=sessionStorage.getItem('deliveryCode');
      //创建二维码
      if (this.qrcode == null) {
        this.$nextTick(() => {
          this.creatQrCode();
        })
      }
      //初始化webSocket
       this.initWebSocket();
    },

     destroyed() {
       this.websock.close() //离开路由之后断开websocket连接
     },

    methods: {
      creatQrCode() {
        this.qrcode = new QRCode(this.$refs.qrCodeUrl, {
          text: this.deliveryCode,
          width: 250,
          height: 250,
          colorDark: '#000000',
          colorLight: '#ffffff',
          correctLevel: QRCode.CorrectLevel.H
        })
      },

      initWebSocket(){ //初始化weosocket
        if(typeof(WebSocket) === "undefined"){
          alert("您的浏览器不支持socket")
        }else {
          const wsuri = "ws://tms.aupri.cn:8079/websocket/"+this.deliveryCode;
          this.websock = new WebSocket(wsuri);
          this.websock.onmessage = this.websocketonmessage;
          this.websock.onopen = this.websocketonopen;
          this.websock.onerror = this.websocketonerror;
          this.websock.onclose = this.websocketclose;
        }
      },
      websocketonopen(){ //连接建立之后执行send方法发送数据
        console.log("websocket连接成功")
        alert("成功");
      },
      websocketonerror(){//连接建立失败重连
        this.initWebSocket();
      },
      websocketonmessage(e){ //数据接收
        console.log("收到消息："+e.data);
       //只要接收到消息就置灰二维码（省略...）


      },
      websocketsend(Data){//数据发送
        this.websock.send(Data);
      },
      websocketclose(e){  //关闭
        console.log('websocket断开连接',e);
        alert("失败");
      },     
  }
</script>

扫码的接口:(在扫码成功之后的接口调用，告诉后台这个二维码被我扫到了)

	@Autowired
    private WebSocketServer webSocketServer;
    
	@GetMapping("/scanSuccess/{deliveryCode}")
    public String scanSuccess(@PathVariable("deliveryCode") String deliveryCode){
    	//
    	webSocketServer.sendOneMessage(deliveryCode, "成功");
        return "success";
    }