PHP Extension

Send and Receive WebSocket Messages

See more WebSocket Examples

This example how to send and receive websocket messages.

A WebSocket message can be composed of one or more frames. The simple case is where a single frame is both the first and last frame in a message. This is the case where the 1st frame in the message has the "final frame" bit set.

This example demonstrates sending and receiving multi-frame messages.

Note: The websockets.chilkat.io server imposes the following limitations:
Messages must be 16K or less, and each connection is limited to a max of 16 echoed messages.

PHP Extension

<?php

include("chilkat.php");

$success = false;

// 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 websockets.chilkat.io
// IMPORTANT: websockets.chilkat.io accepts frames of up to 16K in size and echoes them back.
// IMPORTANT: The websockets.chilkat.io server imposes the following limitations: 
// ---------- Messages must be 16K or less, and each connection is limited to a max of 16 echoed messages.
$success = $rest->Connect('websockets.chilkat.io',80,false,false);
$ws->UseConnection($rest);
$ws->AddClientHeaders();
$responseBodyIgnored = $rest->fullRequestNoBody('GET','/wsChilkatEcho.ashx');
$success = $ws->ValidateServerHandshake();
if ($success != true) {
    print $ws->lastErrorText() . "\n";
    exit;
}

// This example demonstrates sending and receiving a multi-frame message.

// The websocket message will be composed of three text lines, each frame will contain a single line.

// Send the 1st frame in the message.
$finalFrame = false;
$success = $ws->SendFrame('This is the 1st frame\r\n',$finalFrame);
if ($success != true) {
    print $ws->lastErrorText() . "\n";
    exit;
}

// Send the 2nd frame in the message.
$success = $ws->SendFrame('This is the 2nd frame\r\n',$finalFrame);
if ($success != true) {
    print $ws->lastErrorText() . "\n";
    exit;
}

// Send the 3rd and final frame in the message.
$finalFrame = true;
$success = $ws->SendFrame('This is the 3rd frame\r\n',$finalFrame);
if ($success != true) {
    print $ws->lastErrorText() . "\n";
    exit;
}

// Read an incoming frames until we receive the final frame.
// Note: It may be that the echo server (websockets.chilkat.io) responds with 
// the full message in a single final frame.
$receivedFinalFrame = false;
while ($receivedFinalFrame == false) {

    $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;
    }

    $receivedFinalFrame = $ws->get_FinalFrame();

    // Show the opcode and final frame bit for the frame just received:
    print 'Frame opcode: ' . $ws->frameOpcode() . "\n";
    print 'Final frame: ' . $receivedFinalFrame . "\n";
}

// Return the message accumulated in the above calls to ReadFrame.
$receivedMsg = $ws->getFrameData();
print 'Received: ' . $receivedMsg . "\n";

// 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;
}

// Should receive the "Close" opcode.
print 'Received opcode: ' . $ws->frameOpcode() . "\n";
// Should be the same status code we sent (1000)
print 'Received close status code: ' . $ws->get_CloseStatusCode() . "\n";
// The server may echo the close reason.  If not, this will be empty.
print 'Echoed close reason: ' . $ws->closeReason() . "\n";

print 'Success.' . "\n";

?>