(C# UWP/WinRT) 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 Universal Windows Platform (UWP) / WinRT Downloads Chilkat for the Universal Windows Platform (UWP)

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

Chilkat.WebSocket ws = new Chilkat.WebSocket();

//  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.

Chilkat.Rest rest = new Chilkat.Rest();

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

string responseBody = await rest.FullRequestNoBodyAsync("GET","/ws");
success = ws.ValidateServerHandshake();
if (success != true) {
    Debug.WriteLine(ws.LastErrorText);
    Debug.WriteLine(responseBody);
    Debug.WriteLine(rest.ResponseHeader);
    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 = await ws.ReadFrameAsync();
if (success != true) {
    Debug.WriteLine("Failed to receive a frame");
    Debug.WriteLine("ReadFrame fail reason = " + Convert.ToString(ws.ReadFrameFailReason));
    Debug.WriteLine(ws.LastErrorText);
    return;
}

//  We should get this:
//  {"event":"info","version":1.1,"platform":{"status":1}}
Debug.WriteLine(ws.GetFrameData());

//  Subscribe to the BTCUSD ticker feed.
//  See https://docs.bitfinex.com/docs for more information.
Chilkat.JsonObject json1 = new Chilkat.JsonObject();
json1.AppendString("event","subscribe");
json1.AppendString("channel","ticker");
json1.AppendString("pair","BTCUSD");

bool finalFrame = true;
success = await ws.SendFrameAsync(json1.Emit(),finalFrame);

//  Subscribe to the ETHUSD ticker feed.
Chilkat.JsonObject json2 = new Chilkat.JsonObject();
json2.AppendString("event","subscribe");
json2.AppendString("channel","ticker");
json2.AppendString("pair","ETHUSD");

success = await ws.SendFrameAsync(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 = await ws.ReadFrameAsync();
    if (success != true) {
        Debug.WriteLine("Failed to receive a frame");
        Debug.WriteLine("ReadFrame fail reason = " + Convert.ToString(ws.ReadFrameFailReason));
        Debug.WriteLine(ws.LastErrorText);
        return;
    }

    //  The responses we desire are in Text frames, where the opcode = 1.
    if (ws.FrameOpcodeInt == 1) {
        string receivedText = ws.GetFrameData();
        Debug.WriteLine(receivedText);
        //  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 = await ws.SendCloseAsync(true,1000,"Closing this websocket.");
if (success != true) {
    Debug.WriteLine(ws.LastErrorText);
    return;
}

//  Read the Close response.
success = await ws.ReadFrameAsync();
if (success != true) {
    Debug.WriteLine("ReadFrame fail reason = " + Convert.ToString(ws.ReadFrameFailReason));
    Debug.WriteLine(ws.LastErrorText);
    return;
}

Debug.WriteLine("Success.");