How to catch exceptions that occur in websocket sharp

[PaulGWebster]

Good day I keep hitting an exception after a few hours of use;

22/11/2020 13:03:07|Fatal|WebSocket.<startReceiving>b__176_2|WebSocketSharp.WebSocketException: The header of a frame cannot be read from the stream.
                             at WebSocketSharp.WebSocketFrame.processHeader(Byte[] header)
                             at WebSocketSharp.WebSocketFrame.<>c__DisplayClass73_0.<readHeaderAsync>b__0(Byte[] bytes)
                             at WebSocketSharp.Ext.<>c__DisplayClass48_0.<ReadBytesAsync>b__0(IAsyncResult ar)
Websocket closed connection

I tried wrapping my entire websocket initialisation and OnBinds in a try {} catch {} but the exception still halts the entire program, what is the correct watch to catch this ... or alternatively catch everything from websocketsharp, basically on failure/error the thread is restarted by main; but it never gets chance as the entire program exits

Example code block (with trys that do not work):

        private void gdaxWebSocketFeed(object passedArgs)
        {
            object[] passedArgsArray = (object[])passedArgs;
​
            ulong packetID = 0;
            int websocketID = (int)passedArgsArray[0];
            Dictionary<int,ConcurrentQueue<string>> sendQueue = 
                (Dictionary<int,ConcurrentQueue<string>>)passedArgsArray[1];
            string wsHost = (string)passedArgsArray[2];
​
            try
            {
                WebSocket wsClient = new WebSocket(wsHost);
                //wsClient.SslConfiguration.EnabledSslProtocols = System.Security.Authentication.SslProtocols.Tls12;
​
                wsClient.OnOpen += (sender, e) =>
                {
                    parentFunction("OPEN", packetID++, new object[] { websocketID, e });
                };
                wsClient.OnError += (sender, e) =>
                {
                    parentFunction("ERROR", packetID++, new object[] { websocketID, "error", e });
                };
                wsClient.OnClose += (sender, e) =>
                {
                    parentFunction("CLOSE", packetID++, new object[] { websocketID, e });
                };
                wsClient.OnMessage += (sender, e) =>
                {
                    GDAXExchangePacket CastJSON =
                        JsonConvert.DeserializeObject<GDAXExchangePacket>(e.Data);
                    parentFunction("MESSAGE", packetID++, new object[] { websocketID, CastJSON, e.Data });
                };
​
                wsClient.Connect();
​
                while (wsClient.IsAlive)
                {
                    if (sendQueue.Count == 0)
                    {
                        Thread.Sleep(100);
                    }
                    else if (sendQueue[websocketID].TryDequeue(out string sendData))
                    {
                        if (sendData != null)
                        {
                            wsClient.Send(sendData);
                        }
                    }
                }
            }
            catch (Exception exception)
            {
                parentFunction("ERROR", packetID++, new object[] { websocketID, "exception", exception.Message });
            }
        }

[mzumbo]

I have the same error: "The header of a frame cannot be read from the stream"

Do yo know how to fix it?

[PaulGWebster]

Yes downgrade the secure websocket to a standard websocket, nginx (gdax for my case):

    server {
        listen       10.200.200.1:8000;

        proxy_ssl_server_name on;

        location / {
                proxy_pass https://ws-feed.pro.coinbase.com;
                proxy_set_header Upgrade $http_upgrade;
                proxy_set_header Connection "Upgrade";
                proxy_http_version 1.1;
                proxy_set_header Host "ws-feed.pro.coinbase.com";
         }
    }

I cannot remember why this worked, remembered after I made the post, but its something to do with long term SSL connections and WSSharp

[manijak]

We use this in a small desktop app that communicates with a web application (angular). Most of the time it works well, but sometimes it gets very unstable and throws the same error you posted. "The header of a frame cannot be read from the stream.".

We mostly see this when the mentioned web application has a successful connection and the user just refreshes the page (F5). Then the connection gets in a "connect-disconnect" loop with the above error. Frequency of the error has increased when we started using SSL.

@sta Do you have any pointers on how we can deal with this or at least how we can pinpoint the issue? I've seen way to many posts about this.

[darkmakukudo]

Have you guys manage to make this work? I'm having a problem right now when connecting websocketsharp to NGINX. Keep getting this error: AM|Fatal|WebSocket.Connect|WebSocketSharp.WebSocketException: The proxy has failed a connection to the requested host and port.

Tried to enable the proxy:

 using (var ws = new WebSocket("ws://localhost:1234/mylocalnginx")) // My backend host
            {
                ws.SetProxy("http://localhost:5556", null, null); // My nginx
                ws.OnMessage += (sender, e) => {
                    Debug.WriteLine("Received a message: " + e.Data);
                };

[eyalpd-lmt]

@darkmakukudo In my case it was a docker from windows. Since windows run ubuntu dockers on WSL, it create a different network, so I had to use host.docker.internal instead of localhost.

https://docs.docker.com/desktop/features/networking/#i-want-to-connect-from-a-container-to-a-service-on-the-host