|
|
(JavaScript) Subscribe to Multiple Bitfinex Tickers on One Connection
Subscribes to multiple ticker symbols on the public Bitfinex websocket ticker channel and receives ticker updates.
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 BTCUSD ticker feed.
// See https://docs.bitfinex.com/docs for more information.
var json1 = new CkJsonObject();
json1.AppendString("event","subscribe");
json1.AppendString("channel","ticker");
json1.AppendString("pair","BTCUSD");
var finalFrame = true;
success = ws.SendFrame(json1.Emit(),finalFrame);
// Subscribe to the ETHUSD ticker feed.
var json2 = new CkJsonObject();
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..
var receivedFinalFrame = false;
var numUpdatesReceived = 0;
while (numUpdatesReceived < 7) {
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]
// 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) {
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.");
|