websocket-client

AMPHP is a collection of event-driven libraries for PHP designed with fibers and concurrency in mind. amphp/websocket-client provides an asynchronous WebSocket client for PHP based on Amp. Websockets are full-duplex communication channels, which are mostly used for realtime communication where the HTTP request / response cycle has too much overhead. They're also used if the server should be able to push data to the client without an explicit request.

There are various use cases for a WebSocket client in PHP, such as consuming realtime APIs, writing tests for a WebSocket server, or controlling web browsers via their remote debugging APIs, which are based on WebSockets.

Installation

This package can be installed as a Composer dependency.

composer require amphp/websocket-client

Requirements

• PHP 8.1+

Connecting

You can create new WebSocket connections using Amp\Websocket\connect(). It accepts a string as first argument, which must use the ws or wss (WebSocket over TLS) scheme. Options can be specified by passing a WebsocketHandshake object instead of a string as first argument, which can also be used to pass additional headers with the initial handshake. The second argument is an optional Cancellation.

<?php

require 'vendor/autoload.php';

use Amp\Websocket\Client;

$connection = Client\connect('ws://localhost:1337/ws');

// do something

Sending Data

WebSocket messages can be sent using the sendText() and sendBinary() methods. Text messages sent with sendText() must be valid UTF-8. Binary messages send with sendBinary() can be arbitrary data.

Both methods return as soon as the message has been fully written to the send buffer. This doesn't mean that the message has been received by the other party or that the message even left the local system's send buffer, yet.

Receiving Data

WebSocket messages can be received using the receive() method. receive() returns once the client has started to receive a message. This allows streaming WebSocket messages, which might be pretty large. In practice, most messages are rather small, and it's fine buffering them completely. receive() returns to a WebsocketMessage, which allows easy buffered and streamed consumption.

Example

use Amp\Websocket\Client\WebsocketHandshake;
use function Amp\Websocket\Client\connect;

// Connects to the websocket endpoint at libwebsockets.org which sends a message every 50ms.
$handshake = (new WebsocketHandshake('wss://libwebsockets.org'))
    ->withHeader('Sec-WebSocket-Protocol', 'dumb-increment-protocol');

$connection = connect($handshake);

while ($message = $connection->receive()) {
    $payload = $message->buffer();

    printf("Received: %s\n", $payload);

    if ($payload === '100') {
        $connection->close();
        break;
    }
}

Versioning

amphp/websocket-client follows the semver semantic versioning specification like all other amphp packages.

Security

If you discover any security related issues, please use the private security issue reporter instead of using the public issue tracker.

License

The MIT License (MIT). Please see LICENSE for more information.