(PHP Extension) Read Bitfinex WebSocket Ticker Channel

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

Chilkat PHP Downloads PHP Extension for Windows, Linux, MacOS, Alpine Linux, Solaris

<?php

// The version number (9_5_0) should match version of the Chilkat extension used, omitting the micro-version number.
// For example, if using Chilkat v9.5.0.48, then include as shown here:
include("chilkat_9_5_0.php");

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

$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.

$rest = new CkRest();

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

$responseBody = $rest->fullRequestNoBody('GET','/ws');
$success = $ws->ValidateServerHandshake();
if ($success != true) {
    print $ws->lastErrorText() . "\n";
    print $responseBody . "\n";
    print $rest->responseHeader() . "\n";
    exit;
}

//  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) {
    print 'Failed to receive a frame' . "\n";
    print 'ReadFrame fail reason = ' . $ws->get_ReadFrameFailReason() . "\n";
    print $ws->lastErrorText() . "\n";
    exit;
}

//  We should get this:
//  {"event":"info","version":1.1,"platform":{"status":1}}
print $ws->getFrameData() . "\n";

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

$finalFrame = true;
$success = $ws->SendFrame($json->emit(),$finalFrame);

//  Read the response.
$success = $ws->ReadFrame();
if ($success != true) {
    print 'Failed to receive a frame' . "\n";
    print 'ReadFrame fail reason = ' . $ws->get_ReadFrameFailReason() . "\n";
    print $ws->lastErrorText() . "\n";
    exit;
}

//  Examine the response
//  We should get this:
//  {"event":"subscribed","channel":"ticker","chanId":2751,"pair":"BTCUSD"}
print $ws->getFrameData() . "\n";

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

    $success = $ws->ReadFrame();
    if ($success != true) {
        print 'Failed to receive a frame' . "\n";
        print 'ReadFrame fail reason = ' . $ws->get_ReadFrameFailReason() . "\n";
        print $ws->lastErrorText() . "\n";
        exit;
    }

    //  The responses we desire are in Text frames, where the opcode = 1.
    if ($ws->get_FrameOpcodeInt() == 1) {
        $receivedText = $ws->getFrameData();
        print $receivedText . "\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]
        $numUpdatesReceived = $numUpdatesReceived + 1;
    }

}

//  Close the websocket connection.
$success = $ws->SendClose(true,1000,'Closing this websocket.');
if ($success != true) {
    print $ws->lastErrorText() . "\n";
    exit;
}

//  Read the Close response.
$success = $ws->ReadFrame();
if ($success != true) {
    print 'ReadFrame fail reason = ' . $ws->get_ReadFrameFailReason() . "\n";
    print $ws->lastErrorText() . "\n";
    exit;
}

print 'Success.' . "\n";

?>