java - WebSocket 握手错误 : Unexpected response code: 302

Question

将基于 REACT 的 WebSocket 客户端连接到基于 Java Jetty 的 Web Socket 服务器时，出现以下错误 -

WebSocket connection to 'ws://localhost:2319/ws' failed: Error during WebSocket handshake: Unexpected response code: 302

通过 Chrome 的智能网络套接字客户端连接时不存在此错误。

我正在尝试开发基于 REACT 的 Web Socket 客户端。客户端代码是 -

var connection = new WebSocket('ws://localhost:2319/ws');
     connection.onopen = function () {
     // connection is opened and ready to use
    };

WebSocket Server 已经基于 Jetty。服务器代码是 -

server = new Server();
    ServerConnector connector = new ServerConnector(server);
    connector.setPort(SSConstants.WWBSOCKET_PORT);
    server.addConnector(connector);

    // Setup the basic application "context" for this application at "/"
    // This is also known as the handler tree (in jetty speak)
    ServletContextHandler context = new ServletContextHandler(ServletContextHandler.SESSIONS);
    context.setContextPath("/ws"); // Set to "/ws" for future integration with the main jetty server.
    server.setHandler(context);

    try {
        // Initialize javax.websocket layer
        ServerContainer wsContainer = WebSocketServerContainerInitializer.configureContext(context);

        // Add WebSocket endpoint to javax.websocket layer
        wsContainer.addEndpoint(WebsocketListener.class);
        server.start();           
    }
    catch (Throwable t) {
        ssLogger.logInfo("Websocket Server start exp : ");
        t.printStackTrace(System.err);
    }

输出-

WebSocket connection to 'ws://localhost:2319/ws' failed: Error during WebSocket handshake: Unexpected response code: 302

Request URL:ws://localhost:2319/ws
Request Method:GET
Status Code:302 Found

Response Headers
view source
Content-Length:0
Date:Fri, 11 Aug 2017 18:51:42 GMT
Location:http://localhost:2319/ws/
Server:Jetty(9.3.8.v20160314)

Request Headers
view source
Accept-Encoding:gzip, deflate, br
Accept-Language:en-US,en;q=0.8
Cache-Control:no-cache
Connection:Upgrade
Host:localhost:2319
Origin:https://localhost:1338
Pragma:no-cache
Sec-WebSocket-Extensions:permessage-deflate; client_max_window_bits
Sec-WebSocket-Key:2OZooIjOX7G6kgNpPOz9Fw==
Sec-WebSocket-Version:13
Upgrade:websocket
User-Agent:Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/60.0.3112.90 Safari/537.36
Name

Answer 1

ws://localhost:2319/ws不是有效的端点 URL/URI，它希望重定向到您声明的正确端点 URL/URI contextPath的 /ws

这就是 302 重定向告诉你的......

Location: http://localhost:2319/ws/

假设您的 WebsocketListener声明为 @ServerEndpoint("/ws") ，我们使用您的 ServletContext在contextPath的 "/ws"这意味着您访问该 websocket 端点的 URL/URI 是 ...

ws://localhost:2319/ws/ws

或者换个说法...

ws://<host>:<port>/<contextPath>/<endpointPath>