Springboot 安装 websocket（有拦截器）

配置依赖

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

消息处理，相当于@OnOpen，@OnClose，@OnMessage等注解的函数

import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;
import org.springframework.web.socket.BinaryMessage;
import org.springframework.web.socket.CloseStatus;
import org.springframework.web.socket.TextMessage;
import org.springframework.web.socket.WebSocketSession;
import org.springframework.web.socket.handler.AbstractWebSocketHandler;


/**
 * @Time : 2022/1/10 10:29
 * @Author : Galaxy
 * @Create : IdeaJ
 * @Project : serverVue
 * @Description :
 */

@Slf4j
@Component
public class WebsocketHandler extends AbstractWebSocketHandler {
    @Override
    public void afterConnectionEstablished(WebSocketSession session) throws Exception {
        //相当于注解 @OnOpen
        log.debug("SESSIONID：{}", session.getId());
    }

    @Override
    public void afterConnectionClosed(WebSocketSession session, CloseStatus status) throws Exception {
        //相当于注解 @OnClose
    }

    @Override
    public void handleTransportError(WebSocketSession session, Throwable exception) throws Exception {
        //相当于注解 @OnError
        if (session.isOpen()) {
            session.close(CloseStatus.BAD_DATA.withReason("Messages transport error"));
        }
    }

    @Override
    protected void handleTextMessage(WebSocketSession session, TextMessage message) throws Exception {
        //相当于注解 @OnMessage
        TextMessage textMessage = new TextMessage("Server has received your message.");
        session.sendMessage(textMessage);
    }

    @Override
    protected void handleBinaryMessage(WebSocketSession session, BinaryMessage message) throws Exception {
        //相当于注解 @OnMessage
        TextMessage textMessage = new TextMessage("Server has received your message.");
        session.sendMessage(textMessage);
    }
}

拦截器

import lombok.extern.slf4j.Slf4j;
import org.springframework.http.server.ServerHttpRequest;
import org.springframework.http.server.ServerHttpResponse;
import org.springframework.http.server.ServletServerHttpRequest;
import org.springframework.stereotype.Component;
import org.springframework.web.socket.WebSocketHandler;
import org.springframework.web.socket.server.HandshakeInterceptor;

import java.util.Map;

/**
 * @Time : 2021/11/25 23:46
 * @Author : Galaxy
 * @Create : IdeaJ
 * @Project : server
 * @Description :
 */
@Slf4j
@Component
public class WebSocketInterceptor implements HandshakeInterceptor {
    @Override
    public boolean beforeHandshake(ServerHttpRequest request, ServerHttpResponse response, WebSocketHandler wsHandler, Map<String, Object> attributes) throws Exception {
        //拦截器 -> 握手开始之前
        log.info("[MyWebSocketInterceptor#BeforeHandshake] Request from " + request.getRemoteAddress().getHostString());

        if (request instanceof ServletServerHttpRequest) {
            ServletServerHttpRequest serverHttpRequest = (ServletServerHttpRequest) request;
            String token = serverHttpRequest.getServletRequest().getHeader("token");
            //这里做一个简单的鉴权，只有符合条件的鉴权才能握手成功
            if ("token-123456".equals(token)) {
                return true;
            } else {
                return false;
            }
        }
        return true;
    }

    @Override
    public void afterHandshake(ServerHttpRequest request, ServerHttpResponse response, WebSocketHandler wsHandler, Exception exception) {
    }
}

config注册类

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.socket.config.annotation.EnableWebSocket;
import org.springframework.web.socket.config.annotation.WebSocketConfigurer;
import org.springframework.web.socket.config.annotation.WebSocketHandlerRegistry;
import top.liheji.config.handler.WebsocketHandler;
import top.liheji.config.intercept.WebSocketInterceptor;

/**
 * @Time : 2021/11/25 23:46
 * @Author : Galaxy
 * @Create : IdeaJ
 * @Project : server
 * @Description :
 */
@Configuration
@EnableWebSocket
public class WebSocketConfig implements WebSocketConfigurer {

    @Autowired
    private WebsocketHandler websocketHandler;

    @Autowired
    private WebSocketInterceptor webSocketInterceptor;

    @Override
    public void registerWebSocketHandlers(WebSocketHandlerRegistry registry) {
        registry
                .addHandler(websocketHandler, "/websocket")
                .addInterceptors(webSocketInterceptor);
    }
}

前端配置

• js代码

var websocket = null;
//判断当前浏览器是否支持WebSocket, 主要此处要更换为自己的地址
if ('WebSocket' in window) {
    websocket = new WebSocket("ws://localhost:8080/websocket");
} else {
    alert('Not support websocket')
}

//连接发生错误的回调方法
websocket.onerror = function () {
    setMessageInnerHTML("error");
};

//连接成功建立的回调方法
websocket.onopen = function (event) {
    //setMessageInnerHTML("open");
}

//接收到消息的回调方法
websocket.onmessage = function (event) {
    setMessageInnerHTML(event.data);
}

//连接关闭的回调方法
websocket.onclose = function () {
    setMessageInnerHTML("close");
}

//监听窗口关闭事件，当窗口关闭时，主动去关闭websocket连接，防止连接还没断开就关闭窗口，server端会抛异常。
window.onbeforeunload = function () {
    websocket.close();
}

//将消息显示在网页上
function setMessageInnerHTML(innerHTML) {
    document.getElementById('message').innerHTML += innerHTML + '<br/>';
}

//关闭连接
function closeWebSocket() {
    websocket.close();
}

//发送消息
function send() {
    var message = document.getElementById('text').value;
    websocket.send(JSON.stringify({
        data: message
    }));
}