(MFC) Subscribe to Multiple Bitfinex Tickers on One Connection

Subscribes to multiple ticker symbols on 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 BTCUSD ticker feed.
    //  See https://docs.bitfinex.com/docs for more information.
    CkJsonObject json1;
    json1.AppendString("event","subscribe");
    json1.AppendString("channel","ticker");
    json1.AppendString("pair","BTCUSD");

    bool finalFrame = true;
    success = ws.SendFrame(json1.emit(),finalFrame);

    //  Subscribe to the ETHUSD ticker feed.
    CkJsonObject json2;
    json2.AppendString("event","subscribe");
    json2.AppendString("channel","ticker");
    json2.AppendString("pair","ETHUSD");

    success = ws.SendFrame(json2.emit(),finalFrame);

    //  Begin reading the ticker feed.
    // / This will include a single confirmation response for each subscription.

    //  We'll just read the 1st 5 updates and then exit..
    bool receivedFinalFrame = false;
    int numUpdatesReceived = 0;
    while (numUpdatesReceived < 7) {

        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]
            //  Initially, a single confirmation response for each subscription would be received, such as this:
            //  {"event":"subscribed","channel":"ticker","chanId":810,"pair":"BTCUSD"}
            numUpdatesReceived = numUpdatesReceived + 1;
        }

    }

    //  This is sample output:
    //  You can see that the 1st message received is the subscription confirmation for the BTCUSD subscribe request.
    //  The next message is a BTCUSD ticker update.
    //  The next message is the confirmation for the ETHUSD subscription.
    //  The next message is an ETHUSD update.
    //  The BTCUSD channel ID is "537", and the ETHUSD channel ID is "700".  The channel IDs are provided in the
    //  subscription confirmation messages.  Each ticker update begins with the channel ID..

    //  {"event":"subscribed","channel":"ticker","chanId":537,"pair":"BTCUSD"}
    //  [537,6457.9,79.59102302,6458,22.49395741,-24.1,-0.0037,6457.9,13644.52820029,6540,6370.76958739]
    //  {"event":"subscribed","channel":"ticker","chanId":700,"pair":"ETHUSD"}
    //  [700,496.9,247.24493326,496.92,284.09636979,-2.47,-0.0049,496.9,74154.05945261,502.85,486.96]
    //  [537,"hb"]
    //  [700,"hb"]
    //  [700,496.92,233.34338276,496.93,431.78867277,-2.45,-0.0049,496.92,74167.99173586,502.85,486.96]

    //  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());

    }