(JavaScript) Read Bitfinex WebSocket Ticker Channel

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

Note

This example is intended for running within a Chilkat.Js embedded JavaScript engine. All Chilkat JavaScript examples require Chilkat v11.4.0 or greater.

var success = false;

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

var ws = new CkWebSocket();

// 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.

var rest = new CkRest();

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

var responseBody = rest.FullRequestNoBody("GET","/ws");
success = ws.ValidateServerHandshake();
if (success !== true) {
    console.log(ws.LastErrorText);
    console.log(responseBody);
    console.log(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 = ws.ReadFrame();
if (success !== true) {
    console.log("Failed to receive a frame");
    console.log("ReadFrame fail reason = " + ws.ReadFrameFailReason);
    console.log(ws.LastErrorText);
    return;
}

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

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

var finalFrame = true;
success = ws.SendFrame(json.Emit(),finalFrame);

// Read the response.
success = ws.ReadFrame();
if (success !== true) {
    console.log("Failed to receive a frame");
    console.log("ReadFrame fail reason = " + ws.ReadFrameFailReason);
    console.log(ws.LastErrorText);
    return;
}

// Examine the response
// We should get this:
// {"event":"subscribed","channel":"ticker","chanId":2751,"pair":"BTCUSD"}
console.log(ws.GetFrameData());

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

    success = ws.ReadFrame();
    if (success !== true) {
        console.log("Failed to receive a frame");
        console.log("ReadFrame fail reason = " + ws.ReadFrameFailReason);
        console.log(ws.LastErrorText);
        return;
    }

    // The responses we desire are in Text frames, where the opcode = 1.
    if (ws.FrameOpcodeInt == 1) {
        var receivedText = ws.GetFrameData();
        console.log(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]
        numUpdatesReceived = numUpdatesReceived+1;
    }

}

// Close the websocket connection.
success = ws.SendClose(true,1000,"Closing this websocket.");
if (success !== true) {
    console.log(ws.LastErrorText);
    return;
}

// Read the Close response.
success = ws.ReadFrame();
if (success !== true) {
    console.log("ReadFrame fail reason = " + ws.ReadFrameFailReason);
    console.log(ws.LastErrorText);
    return;
}

console.log("Success.");