在Android上使用Socket.IO始终返回XHR轮询错误 [英] Using Socket.IO on android Always Returns XHR Poll Error

问题描述

我正在编写一个需要连接到node.js服务器上运行的Socket.IO实例的Android应用程序。

I am writing an android app that needs to connect to a Socket.IO instance running on a node.js server.

尝试连接到实例并进行传输使用iOS设备的数据运行完美，但是当我尝试使用Android设备时，它会失败。

Attempting to connect to the instance and transmitting data using an iOS device works flawlessly, but when I try to do it with an android device it fails.

我正在使用原生java客户端，这是我在android端使用的代码：

I am using the Native java client, and this is the code I'm using on the android side:

mManager = new Manager(new URI("https://example.com"));
mSocket = mManager.socket("/users");

// socket events listeners
    mSocket.on(Socket.EVENT_CONNECTING, new Emitter.Listener() {
        @Override
        public void call(Object... args) {
            Log.v(TAG, "Caught EVENT_CONNECTING");
            for (Object obj : args) {
                Log.v(TAG, "Errors :: " + obj);
            }
        }
    }).on(Socket.EVENT_CONNECT, new Emitter.Listener() {
        @Override
        public void call(Object... args) {
            Log.v(TAG, "connected to the backend");
            Log.v(TAG, String.format("JSON Obj to emit: %s", jsonObject.toString()));
            mSocket.emit("hello_packet", jsonObject);
        }
    }).on(Socket.EVENT_RECONNECTING, new Emitter.Listener() {
        @Override
        public void call(Object... args) {
            Log.v(TAG, "Caught EVENT_RECONNECTING");
            for (Object obj : args) {
                Log.v(TAG, "Errors :: " + obj);
            }
        }
    }).on(Socket.EVENT_DISCONNECT, new Emitter.Listener() {
        @Override
        public void call(Object... args) {
            Log.v(TAG, "Socket disconnected");
        }
    }).on(Socket.EVENT_ERROR, new Emitter.Listener() {
        @Override
        public void call(Object... args) {
            Log.v(TAG, "Caught EVENT_ERROR");
            for (Object obj : args) {
                Log.v(TAG, "Errors :: " + obj);
            }
        }
    }).on(Socket.EVENT_CONNECT_ERROR, new Emitter.Listener() {
        @Override
        public void call(Object... args) {
            Log.v(TAG, "Caught EVENT_CONNECT_ERROR");
            for (Object obj : args) {
                Log.v(TAG, "Errors :: " + obj);
            }
        }
    });

    Log.v(TAG, "Connecting socket");
    mSocket.connect();

每当我尝试连接时（基本上只要行 mSocket.connect （）; ）日志打印以下行：

Whenever I try to connect (Basically as soon as the line mSocket.connect();) The log prints the following lines:

05-07 22:41:36.684 15552-15552/com.my.app V/Main Activity: Connecting socket
05-07 22:41:36.699 15552-15858/com.my.app V/Main Activity: Caught EVENT_CONNECTING
05-07 22:41:36.926 15552-15866/com.my.app V/Main Activity: Caught EVENT_CONNECT_ERROR
05-07 22:41:36.926 15552-15866/com.my.app V/Main Activity: Errors :: io.socket.engineio.client.EngineIOException: xhr poll error
05-07 22:41:38.189 15552-15884/com.my.app V/Main Activity: Caught EVENT_RECONNECTING
05-07 22:41:38.189 15552-15884/com.my.app V/Main Activity: Errors :: 1
05-07 22:41:38.207 15552-15887/com.my.app V/Main Activity: Caught EVENT_CONNECT_ERROR
05-07 22:41:38.208 15552-15887/com.my.app V/Main Activity: Errors :: io.socket.engineio.client.EngineIOException: xhr poll error
05-07 22:41:39.518 15552-15911/com.my.app V/Main Activity: Caught EVENT_RECONNECTING
05-07 22:41:39.518 15552-15911/com.my.app V/Main Activity: Errors :: 2
05-07 22:41:39.531 15552-15915/com.my.app V/Main Activity: Caught EVENT_CONNECT_ERROR
05-07 22:41:39.531 15552-15915/com.my.app V/Main Activity: Errors :: io.socket.engineio.client.EngineIOException: xhr poll error
05-07 22:41:41.846 15552-15949/com.my.app V/Main Activity: Caught EVENT_RECONNECTING
05-07 22:41:41.846 15552-15949/com.my.app V/Main Activity: Errors :: 3
05-07 22:41:41.857 15552-15953/com.my.app V/Main Activity: Caught EVENT_CONNECT_ERROR
05-07 22:41:41.857 15552-15953/com.my.app V/Main Activity: Errors :: io.socket.engineio.client.EngineIOException: xhr poll error
05-07 22:41:46.863 15552-16025/com.my.app V/Main Activity: Caught EVENT_RECONNECTING
05-07 22:41:46.864 15552-16025/com.my.app V/Main Activity: Errors :: 4
05-07 22:41:46.879 15552-16029/com.my.app V/Main Activity: Caught EVENT_CONNECT_ERROR
05-07 22:41:46.879 15552-16029/com.my.app V/Main Activity: Errors :: io.socket.engineio.client.EngineIOException: xhr poll error
05-07 22:41:51.883 15552-16126/com.my.app V/Main Activity: Caught EVENT_RECONNECTING
05-07 22:41:51.883 15552-16126/com.my.app V/Main Activity: Errors :: 5
05-07 22:41:51.895 15552-16130/com.my.app V/Main Activity: Caught EVENT_CONNECT_ERROR
05-07 22:41:51.895 15552-16130/com.my.app V/Main Activity: Errors :: io.socket.engineio.client.EngineIOException: xhr poll error
05-07 22:41:56.900 15552-16236/com.my.app V/Main Activity: Caught EVENT_RECONNECTING
05-07 22:41:56.900 15552-16236/com.my.app V/Main Activity: Errors :: 6
05-07 22:41:56.921 15552-16240/com.my.app V/Main Activity: Caught EVENT_CONNECT_ERROR
05-07 22:41:56.921 15552-16240/com.my.app V/Main Activity: Errors :: io.socket.engineio.client.EngineIOException: xhr poll error
05-07 22:42:01.927 15552-16357/com.my.app V/Main Activity: Caught EVENT_RECONNECTING
05-07 22:42:01.927 15552-16357/com.my.app V/Main Activity: Errors :: 7
05-07 22:42:01.945 15552-16361/com.my.app V/Main Activity: Caught EVENT_CONNECT_ERROR
05-07 22:42:01.945 15552-16361/com.my.app V/Main Activity: Errors :: io.socket.engineio.client.EngineIOException: xhr poll error
05-07 22:42:06.951 15552-16466/com.my.app V/Main Activity: Caught EVENT_RECONNECTING
05-07 22:42:06.952 15552-16466/com.my.app V/Main Activity: Errors :: 8
05-07 22:42:06.969 15552-16470/com.my.app V/Main Activity: Caught EVENT_CONNECT_ERROR
05-07 22:42:06.970 15552-16470/com.my.app V/Main Activity: Errors :: io.socket.engineio.client.EngineIOException: xhr poll error
05-07 22:42:11.975 15552-16545/com.my.app V/Main Activity: Caught EVENT_RECONNECTING
05-07 22:42:11.976 15552-16545/com.my.app V/Main Activity: Errors :: 9
05-07 22:42:11.994 15552-16549/com.my.app V/Main Activity: Caught EVENT_CONNECT_ERROR
05-07 22:42:11.994 15552-16549/com.my.app V/Main Activity: Errors :: io.socket.engineio.client.EngineIOException: xhr poll error
05-07 22:42:17.000 15552-16629/com.my.app V/Main Activity: Caught EVENT_RECONNECTING
05-07 22:42:17.000 15552-16629/com.my.app V/Main Activity: Errors :: 10
05-07 22:42:17.012 15552-16633/com.my.app V/Main Activity: Caught EVENT_CONNECT_ERROR
05-07 22:42:17.012 15552-16633/com.my.app V/Main Activity: Errors :: io.socket.engineio.client.EngineIOException: xhr poll error
05-07 22:42:22.017 15552-16710/com.my.app V/Main Activity: Caught EVENT_RECONNECTING
05-07 22:42:22.017 15552-16710/com.my.app V/Main Activity: Errors :: 11
05-07 22:42:22.033 15552-16714/com.my.app V/Main Activity: Caught EVENT_CONNECT_ERROR
05-07 22:42:22.033 15552-16714/com.my.app V/Main Activity: Errors :: io.socket.engineio.client.EngineIOException: xhr poll error
05-07 22:42:27.039 15552-16788/com.my.app V/Main Activity: Caught EVENT_RECONNECTING
05-07 22:42:27.039 15552-16788/com.my.app V/Main Activity: Errors :: 12
05-07 22:42:27.056 15552-16792/com.my.app V/Main Activity: Caught EVENT_CONNECT_ERROR
05-07 22:42:27.056 15552-16792/com.my.app V/Main Activity: Errors :: io.socket.engineio.client.EngineIOException: xhr poll error
05-07 22:42:32.061 15552-16957/com.my.app V/Main Activity: Caught EVENT_RECONNECTING
05-07 22:42:32.062 15552-16957/com.my.app V/Main Activity: Errors :: 13

因此我尝试连接后立即收到xhr轮询错误并且以下所有连接尝试都会遇到相同的结果。

So I immediately get an xhr poll error after attempting to connect and all following connection attempts meet the same result.

我看到一些帖子说这样的问题可能是由SSL证书问题导致的，尽管我做的任何尝试都是Socket.IO库使用的SSL上下文不起作用。

I saw some posts saying such an issue might be cause by an SSL certificate issue though any attempts I made to temper with the SSL Context the Socket.IO library uses didn't work.

如果任何人知道我可能尝试使其工作，那将是非常好的。

If anyoen has an idea what I might be able to try to get this to work it would be excellent.

如有任何信息或者代码样本缺失，请告诉我，我会添加它们。

If any information or code sampels are missing, let me know and I'll add them.

推荐答案

经过进一步测试后，我发现了以下内容： / p>

After further testing I found the following:

1. 如果在遇到不同事件时调试套接字（即EVENT_ERROR），您捕获的异常将包含从您尝试访问的地址收到的响应代码。


2. 在我尝试使用HTTP访问我的服务器的情况下，我收到了301响应代码，因为我尝试过的URL会自动将我重定向到HTTPS地址。


3. 当尝试访问HTTPS地址时，我收到了401响应代码 - 这意味着我的套接字发出的请求已到达服务器但是未授权 - 原因是目标服务器已打开基本身份验证，并且我未在套接字请求标头中提供所需的凭据。


4. 在提供了所需的头文件之后，我设法正确地连接到套接字服务器，但是当发出请求时它失败了，我的套接字又回到了重新连接尝试循环 - 原因是我发送给服务器的JSON我的Android手机不是预期的格式，服务器无法收到请求。

1. If you debug your socket when you encounter different events (i.e. EVENT_ERROR), the exception you catch will contain the response code received from the address you tried to reach.
2. In my case when attempting to reach my server with HTTP I received a 301 response code because the URL I tried reaching automatically redirected me to the HTTPS address.
3. When attempting to reach the HTTPS address I received a 401 response code - meaning the request my socket made had reached the server but was not authorized - The reason for that was that the target server had basic authentication turned on and I didn't supply the required credentials in the socket request headers.
4. After supplying the required headers I managed to connect to the socket server properly, but when sending out a request it failed and my socket went back to a re-connection attempt loop - The reason for that was that the JSON I sent to the server from my Android phone was not in the format expected and the server failed to receive that request.

我用来向套接字请求添加基本身份验证标头的代码：

The code I used to add a basic authentication header to my socket request:

// Adding authentication headers when encountering EVENT_TRANSPORT
mSocket.io().on(Manager.EVENT_TRANSPORT, new Emitter.Listener() {
    @Override
    public void call(Object... args) {
        Transport transport = (Transport) args[0];
        // Adding headers when EVENT_REQUEST_HEADERS is called
        transport.on(Transport.EVENT_REQUEST_HEADERS, new Emitter.Listener() {
            @Override
            public void call(Object... args) {
                Log.v(TAG, "Caught EVENT_REQUEST_HEADERS after EVENT_TRANSPORT, adding headers");
                Map<String, List<String>> mHeaders = (Map<String, List<String>>)args[0];
                mHeaders.put("Authorization", Arrays.asList("Basic bXl1c2VyOm15cGFzczEyMw=="));
            }
        });
    }
});

如果在尝试使用Socket.IO时遇到XHR轮询错误，请确保连接您的套接字服务器是可用的，并且您正确连接。最后在我的情况下，所有这些都围绕着需要基本身份验证的服务器而且在联系服务器时我没有提供它。

If you encounter and XHR Poll error when you attempt to use Socket.IO, make sure that the connection to your socket server is available and that you are connecting properly. In the end in my case it all revolved around the server requiring basic authentication and me not supplying it when contacting the server.

同样，因为在尝试解决此问题时，我遇到了一些解决方案 - 尝试通过HTTPS访问服务器时，通常不需要特殊主机名验证程序或特殊证书管理器。尽量避免使用此类解决方案，因为它们会极大地损害您应用的安全性。

Also, because I encountered that solution qutie a bit while trying to sovle this issue - When trying to reach your server over HTTPS, you usually don't need a special hostname verifier or special certificate manager. Try and avoid such solutions as they greatly harm the security of your app.

这篇关于在Android上使用Socket.IO始终返回XHR轮询错误的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！