(Perl) WebSocket Send/Receive Binary Data

Demonstrates how to send and receive binary data on a websocket. This example uses Chilkat's websocket test echo server at ws://websockets.chilkat.io/wsChilkatEcho.ashx

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.

Chilkat Perl Downloads Perl Module for Windows, MacOS, Linux, Alpine Linux, Solaris

use chilkat();

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

$ws = chilkat::CkWebSocket->new();

# 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 = chilkat::CkRest->new();
# 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",80,0,0);
$ws->UseConnection($rest);
$ws->AddClientHeaders();
$responseBodyIgnored = $rest->fullRequestNoBody("GET","/wsChilkatEcho.ashx");
$success = $ws->ValidateServerHandshake();
if ($success != 1) {
    print $ws->lastErrorText() . "\r\n";
    exit;
}

# This example sends a small JPG file (about 7KB) in a websocket frame.
$jpgData = chilkat::CkBinData->new();
$success = $jpgData->LoadFile("qa_data/jpg/starfish.jpg");

print "Number of bytes to send = " . $jpgData->get_NumBytes() . "\r\n";

# Send a frame containing the JPG image data.
# This will be the first and final frame, and therefore this constitutes the entire message.
$finalFrame = 1;
$success = $ws->SendFrameBd($jpgData,$finalFrame);
if ($success != 1) {
    print $ws->lastErrorText() . "\r\n";
    exit;
}

# Read the echoed binary frame(s).
# (We sent the JPG file in a single frame, but we may receive the echo in multiple frames, but it will be one message.)
# Read an incoming frames until we receive the final frame.
$receivedFinalFrame = 0;
while ($receivedFinalFrame == 0) {

    # The ws object is accumulating the received data internally.  Once we get the final frame, we'll get the 
    # accumulated data which should constitute the entire JPG.
    $success = $ws->ReadFrame();
    if ($success != 1) {
        print "Failed to receive a frame" . "\r\n";
        print "ReadFrame fail reason = " . $ws->get_ReadFrameFailReason() . "\r\n";
        print $ws->lastErrorText() . "\r\n";
        exit;
    }

    $receivedFinalFrame = $ws->get_FinalFrame();

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

# Get the accumulated received data.
$jpgReceivedData = chilkat::CkBinData->new();
$ws->GetFrameDataBd($jpgReceivedData);
print "Received " . $jpgReceivedData->get_NumBytes() . " bytes" . "\r\n";

# Save the received JPG to a file so we can check it..
$jpgReceivedData->WriteFile("qa_output/starfish_ws.jpg");

# Close the websocket connection.
$success = $ws->SendClose(1,1000,"Closing this websocket.");
if ($success != 1) {
    print $ws->lastErrorText() . "\r\n";
    exit;
}

# Read the Close response.
$success = $ws->ReadFrame();
if ($success != 1) {
    print "ReadFrame fail reason = " . $ws->get_ReadFrameFailReason() . "\r\n";
    print $ws->lastErrorText() . "\r\n";
    exit;
}

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

print "Success." . "\r\n";