(MFC) Read Bitfinex WebSocket Ticker Channel

Subscribes to the public Bitfinex websocket ticker channel and receives ticker updates.

Chilkat C/C++ Library Downloads MS Visual C/C++ Libs

See Also: Using MFC CString in Chilkat

#include <CkWebSocket.h>
#include <CkRest.h>
#include <CkJsonObject.h>

void ChilkatSample(void)
    {
    CkString strOut;

    //  This example requires the Chilkat API to have been previously unlocked.
    //  See Global Unlock Sample for sample code.

    CkWebSocket ws;

    //  For brevity, this example does not check for errors when etablishing the WebSocket connection.
    //  See Establish WebSocket Connection for more complete sample code for making the connection.

    CkRest rest;

    //  Connect to api.bitfinex.com
    bool success = rest.Connect("api.bitfinex.com",443,true,false);
    ws.UseConnection(rest);
    ws.AddClientHeaders();

    const char *responseBody = rest.fullRequestNoBody("GET","/ws");
    success = ws.ValidateServerHandshake();
    if (success != true) {
        strOut.append(ws.lastErrorText());
        strOut.append("\r\n");
        strOut.append(responseBody);
        strOut.append("\r\n");
        strOut.append(rest.responseHeader());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    //  After connecting, the bitfinex websocket server will send
    //  an info message that contains the actual version of the websocket stream.
    //  Receive that message..
    success = ws.ReadFrame();
    if (success != true) {
        strOut.append("Failed to receive a frame");
        strOut.append("\r\n");
        strOut.append("ReadFrame fail reason = ");
        strOut.appendInt(ws.get_ReadFrameFailReason());
        strOut.append("\r\n");
        strOut.append(ws.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    //  We should get this:
    //  {"event":"info","version":1.1,"platform":{"status":1}}
    strOut.append(ws.getFrameData());
    strOut.append("\r\n");

    //  Subscribe to the public ticker feed.
    //  See https://docs.bitfinex.com/docs for more information.
    CkJsonObject json;
    json.AppendString("event","subscribe");
    json.AppendString("channel","ticker");
    json.AppendString("pair","BTCUSD");

    bool finalFrame = true;
    success = ws.SendFrame(json.emit(),finalFrame);

    //  Read the response.
    success = ws.ReadFrame();
    if (success != true) {
        strOut.append("Failed to receive a frame");
        strOut.append("\r\n");
        strOut.append("ReadFrame fail reason = ");
        strOut.appendInt(ws.get_ReadFrameFailReason());
        strOut.append("\r\n");
        strOut.append(ws.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    //  Examine the response
    //  We should get this:
    //  {"event":"subscribed","channel":"ticker","chanId":2751,"pair":"BTCUSD"}
    strOut.append(ws.getFrameData());
    strOut.append("\r\n");

    //  Begin reading the ticker feed.
    //  We'll just read the 1st 5 updates and then exit..
    bool receivedFinalFrame = false;
    int numUpdatesReceived = 0;
    while (numUpdatesReceived < 5) {

        success = ws.ReadFrame();
        if (success != true) {
            strOut.append("Failed to receive a frame");
            strOut.append("\r\n");
            strOut.append("ReadFrame fail reason = ");
            strOut.appendInt(ws.get_ReadFrameFailReason());
            strOut.append("\r\n");
            strOut.append(ws.lastErrorText());
            strOut.append("\r\n");
            SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
            return;
        }

        //  The responses we desire are in Text frames, where the opcode = 1.
        if (ws.get_FrameOpcodeInt() == 1) {
            const char *receivedText = ws.getFrameData();
            strOut.append(receivedText);
            strOut.append("\r\n");
            //  Should receive a line of text such as this:
            //  [2751,7349,36.34269559,7349.1,41.01777063,-116.2,-0.0156,7349.1,22188.26055319,7560,7270.5]
            numUpdatesReceived = numUpdatesReceived + 1;
        }

    }

    //  Close the websocket connection.
    success = ws.SendClose(true,1000,"Closing this websocket.");
    if (success != true) {
        strOut.append(ws.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    //  Read the Close response.
    success = ws.ReadFrame();
    if (success != true) {
        strOut.append("ReadFrame fail reason = ");
        strOut.appendInt(ws.get_ReadFrameFailReason());
        strOut.append("\r\n");
        strOut.append(ws.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    strOut.append("Success.");
    strOut.append("\r\n");


    SetDlgItemText(IDC_EDIT1,strOut.getUnicode());

    }