DataFlex
DataFlex
Subscribe to Multiple Bitfinex Tickers on One Connection
See more WebSocket Examples
Subscribes to multiple ticker symbols on the public Bitfinex websocket ticker channel and receives ticker updates.Chilkat DataFlex Downloads
Use ChilkatAx-win32.pkg
Procedure Test
Boolean iSuccess
Handle hoWs
Variant vRest
Handle hoRest
String sResponseBody
Handle hoJson1
Boolean iFinalFrame
Handle hoJson2
Boolean iReceivedFinalFrame
Integer iNumUpdatesReceived
String sReceivedText
String sTemp1
Integer iTemp1
Move False To iSuccess
// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.
Get Create (RefClass(cComChilkatWebSocket)) To hoWs
If (Not(IsComObjectCreated(hoWs))) Begin
Send CreateComObject of hoWs
End
// 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.
Get Create (RefClass(cComChilkatRest)) To hoRest
If (Not(IsComObjectCreated(hoRest))) Begin
Send CreateComObject of hoRest
End
// Connect to api.bitfinex.com
Get ComConnect Of hoRest "api.bitfinex.com" 443 True False To iSuccess
Get pvComObject of hoRest to vRest
Get ComUseConnection Of hoWs vRest To iSuccess
Get ComAddClientHeaders Of hoWs To iSuccess
Get ComFullRequestNoBody Of hoRest "GET" "/ws" To sResponseBody
Get ComValidateServerHandshake Of hoWs To iSuccess
If (iSuccess <> True) Begin
Get ComLastErrorText Of hoWs To sTemp1
Showln sTemp1
Showln sResponseBody
Get ComResponseHeader Of hoRest To sTemp1
Showln sTemp1
Procedure_Return
End
// After connecting, the bitfinex websocket server will send
// an info message that contains the actual version of the websocket stream.
// Receive that message..
Get ComReadFrame Of hoWs To iSuccess
If (iSuccess <> True) Begin
Showln "Failed to receive a frame"
Get ComReadFrameFailReason Of hoWs To iTemp1
Showln "ReadFrame fail reason = " iTemp1
Get ComLastErrorText Of hoWs To sTemp1
Showln sTemp1
Procedure_Return
End
// We should get this:
// {"event":"info","version":1.1,"platform":{"status":1}}
Get ComGetFrameData Of hoWs To sTemp1
Showln sTemp1
// Subscribe to the BTCUSD ticker feed.
// See https://docs.bitfinex.com/docs for more information.
Get Create (RefClass(cComChilkatJsonObject)) To hoJson1
If (Not(IsComObjectCreated(hoJson1))) Begin
Send CreateComObject of hoJson1
End
Get ComAppendString Of hoJson1 "event" "subscribe" To iSuccess
Get ComAppendString Of hoJson1 "channel" "ticker" To iSuccess
Get ComAppendString Of hoJson1 "pair" "BTCUSD" To iSuccess
Move True To iFinalFrame
Get ComEmit Of hoJson1 To sTemp1
Get ComSendFrame Of hoWs sTemp1 iFinalFrame To iSuccess
// Subscribe to the ETHUSD ticker feed.
Get Create (RefClass(cComChilkatJsonObject)) To hoJson2
If (Not(IsComObjectCreated(hoJson2))) Begin
Send CreateComObject of hoJson2
End
Get ComAppendString Of hoJson2 "event" "subscribe" To iSuccess
Get ComAppendString Of hoJson2 "channel" "ticker" To iSuccess
Get ComAppendString Of hoJson2 "pair" "ETHUSD" To iSuccess
Get ComEmit Of hoJson2 To sTemp1
Get ComSendFrame Of hoWs sTemp1 iFinalFrame To iSuccess
// 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..
Move False To iReceivedFinalFrame
Move 0 To iNumUpdatesReceived
While (iNumUpdatesReceived < 7)
Get ComReadFrame Of hoWs To iSuccess
If (iSuccess <> True) Begin
Showln "Failed to receive a frame"
Get ComReadFrameFailReason Of hoWs To iTemp1
Showln "ReadFrame fail reason = " iTemp1
Get ComLastErrorText Of hoWs To sTemp1
Showln sTemp1
Procedure_Return
End
// The responses we desire are in Text frames, where the opcode = 1.
Get ComFrameOpcodeInt Of hoWs To iTemp1
If (iTemp1 = 1) Begin
Get ComGetFrameData Of hoWs To sReceivedText
Showln sReceivedText
// 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"}
Move (iNumUpdatesReceived + 1) To iNumUpdatesReceived
End
Loop
// 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.
Get ComSendClose Of hoWs True 1000 "Closing this websocket." To iSuccess
If (iSuccess <> True) Begin
Get ComLastErrorText Of hoWs To sTemp1
Showln sTemp1
Procedure_Return
End
// Read the Close response.
Get ComReadFrame Of hoWs To iSuccess
If (iSuccess <> True) Begin
Get ComReadFrameFailReason Of hoWs To iTemp1
Showln "ReadFrame fail reason = " iTemp1
Get ComLastErrorText Of hoWs To sTemp1
Showln sTemp1
Procedure_Return
End
Showln "Success."
End_Procedure