Socket does not connect to Thingspeak

Netduino Development
1

Hi,

I have been using application Thingspeak for a while to post data. Suddenly it stopped working. After some debugging it seems the Netduino hangs when trying to connect the socket ( socket.connect(remoteEndPoint)). This only happens for api.thingspeak.com. If i try a local url or e.g. google.com the socket connection happens without any problems. Connecting to api.thingspeak.com from other devices ( POST test on my laptop ) works without problems. I have spend two days trying to figure out what could be wrong without results.

Can anyone help me ??

Br, Arno

2

Perhaps this will lead you in the right direction.

Untitled.png948×483 20.2 KB

3

Hi Stephen,

Thanks for picking up my problem. My Thingspeak account is still active and I can post data with a Google test app to POST a message. It is only the Netduino ( 2 PLUS ) which hangs on socket connect.

Are you using Netduino to connect to Thingspeak ? If yes, what code are you using to connect ?

Arno

4

No, I am not using a Netduino 2+ for thingspeak. So I would not have any code to share with you.

5

Hi

Do you have a small sample that I could have a look at to debug?

Have you got code which dumps the Network config on startup?

Regards

@KiwiBryn

6

Hi, I found some code examples for Thingspeak and implemented those on the NP2. A bit to my surprise this is working now so the problem is somehow solved though i still do not understand why my current code suddenly stopped working. My not working code is:

public static void POSTToThingspeak(string data, int connectTimeout)
{
string host = “api.thingspeak.com”;
//Debug.Print(“Trying to send POST data to Thingsspeak server”);
IPEndPoint remoteEndPoint = new IPEndPoint(Dns.GetHostEntry(host).AddressList[0], 80);
try
{
Socket connection = new SocketConnectWithTimeOut(remoteEndPoint, connectTimeout, “tcp”).Connect();
SendThingspeakPOSTRequest(connection, data);
connection.Close();
//Debug.Print(“Ready sending POST data to Thingsspeak”);
}
catch (SocketException e)
{
Debug.Print("connection error for: " + remoteEndPoint.Address.ToString() + e.Message + e.ErrorCode.ToString());
if (e.ErrorCode == 10038) Debug.Print(“Socket Timeout error 10038”);
}
catch (SocketTimeoutException e)
{
Debug.Print("Socket Timeout error " + e.Message);
}
catch (Exception e)
{
Debug.Print("connection error for: " + remoteEndPoint.Address.ToString() + e.Message);
}

    }

    public static void SendThingspeakPOSTRequest(Socket s, string content)
    {
        //Debug.Print("Sending message: ");
        //Debug.Print(content);
        byte[] contentBuffer = Encoding.UTF8.GetBytes(content);
        var requestLine = "POST /update HTTP/1.1" + CRLF;
        byte[] requestLineBuffer = Encoding.UTF8.GetBytes(requestLine);
        var headers =
            "Host: api.thingsspeak.com" + CRLF +
            "Content-Type: application/x-www-form-urlencoded" + CRLF +
            "Connection: close" + CRLF +
            "Content-Length: " + contentBuffer.Length + CRLF +
            CRLF;
        byte[] headersBuffer = Encoding.UTF8.GetBytes(headers);
        s.SendTimeout = connectionTimeOut;
        s.Send(requestLineBuffer);
        s.Send(headersBuffer);
        s.Send(contentBuffer);
        //     string response = HTTP_Methods.ReadResponse(s);
        string response = HTTP_Methods.HTTPReceive(s);
        //     string HTTPStatusCode = HTTP_Methods.DigestHTTPHeader(response, "Status-Code");
        //     Debug.Print("Received status from: " + uri + " : " + HTTPStatusCode);
        //           Debug.Print("Received response: ");
        //           Debug.Print(response);
        string HTTPStatusCode = HTTP_Methods.DigestHTTPHeader(response, "Status-Code");
        Debug.Print("Received response: " + HTTPStatusCode);
        //            Debug.Print(response);
        s.Close();
    }