基于若依框架开发WebSocket接口

添加依赖

在项目的pom.xml文件中添加WebSocket依赖。若依框架默认可能未包含WebSocket支持，需手动引入：

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

配置WebSocket

创建配置类启用WebSocket支持，并注册WebSocket处理器：

@Configuration
@EnableWebSocket
public class WebSocketConfig implements WebSocketConfigurer {
    @Override
    public void registerWebSocketHandlers(WebSocketHandlerRegistry registry) {
        registry.addHandler(myWebSocketHandler(), "/ws")
                .setAllowedOrigins("*");
    }

    @Bean
    public WebSocketHandler myWebSocketHandler() {
        return new MyWebSocketHandler();
    }
}

实现WebSocket处理器

自定义处理器继承TextWebSocketHandler，处理连接、消息和关闭事件：

public class MyWebSocketHandler extends TextWebSocketHandler {
    private static final Set<WebSocketSession> sessions = new CopyOnWriteArraySet<>();

    @Override
    public void afterConnectionEstablished(WebSocketSession session) {
        sessions.add(session);
        System.out.println("New connection: " + session.getId());
    }

    @Override
    protected void handleTextMessage(WebSocketSession session, TextMessage message) {
        System.out.println("Received message: " + message.getPayload());
        for (WebSocketSession s : sessions) {
            try {
                s.sendMessage(new TextMessage("Echo: " + message.getPayload()));
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    @Override
    public void afterConnectionClosed(WebSocketSession session, CloseStatus status) {
        sessions.remove(session);
        System.out.println("Connection closed: " + session.getId());
    }
}

前端连接WebSocket

在Vue或HTML页面中建立WebSocket连接：

const socket = new WebSocket('ws://localhost:8080/ws');
socket.onopen = function() {
    console.log('WebSocket connected');
    socket.send('Hello Server');
};
socket.onmessage = function(event) {
    console.log('Message from server: ', event.data);
};

若依集成注意事项

1. 权限控制：若需结合若依的权限系统，可在WebSocket握手时验证Token，例如通过HandshakeInterceptor。
2. 消息广播：结合Redis发布订阅功能实现集群环境下的消息广播。
3. 心跳检测：客户端需定期发送心跳包，避免连接被意外关闭。

示例：握手拦截器

添加权限验证拦截器：

public class AuthHandshakeInterceptor implements HandshakeInterceptor {
    @Override
    public boolean beforeHandshake(ServerHttpRequest request, ServerHttpResponse response, 
                                   WebSocketHandler wsHandler, Map<String, Object> attributes) {
        String token = ((ServletServerHttpRequest) request).getServletRequest().getParameter("token");
        // 验证Token逻辑
        return true; // 验证通过返回true
    }

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

在配置类中注册拦截器：

registry.addHandler(myWebSocketHandler(), "/ws")
       .addInterceptors(new AuthHandshakeInterceptor())
       .setAllowedOrigins("*");

通过以上步骤，即可在若依框架中实现基础的WebSocket通信功能。