Ably Pub/Sub PHP SDK

The PHP SDK for Ably Pub/Sub: publish messages to channels, read message history and presence, and issue tokens for your users, from servers over HTTP.

Overview

This SDK provides the server package only, for trusted backends authenticating with an API key. There is no device package; for end-user devices, use a device SDK such as JavaScript, Swift/Objective-C, Java/Android, .NET or Flutter.

Package	Use it for	Entry point
ably/pubsub-server	Servers and other trusted backend environments	Ably\PubSub\Server::createHttpClient()

Requirements

PHP 8.1 or later (tested on 8.1 to 8.5), with the curl, json and openssl extensions.

Installation

composer require ably/pubsub-server

Quick start

Use an API key on a server. The samples read it from the ABLY_API_KEY environment variable; set it to an API key from your Ably dashboard. The following code publishes a message over HTTP, then reads the channel's history.

<?php
require __DIR__ . '/vendor/autoload.php';

use Ably\PubSub\Server;

$ablyApiKey = getenv('ABLY_API_KEY');
$client = Server::createHttpClient(['key' => $ablyApiKey]);
$channel = $client->channels->get('test-channel');

$channel->publish('test-event', 'hello world');

$history = $channel->history();
foreach ($history->items as $message) {
    echo "Received: {$message->name}: {$message->data}\n";
}

A failed request throws an Ably\PubSub\Exceptions\AblyException.

Always create clients with Server::createHttpClient(). A client created with new PubSubHttpClient(...) does not declare itself as a server.

Important

Server clients must authenticate with an API key. To use a token instead, see Server clients and token authentication.

The following script issues token requests at /ably-auth. Devices using a device SDK set authUrl to its URL, for example https://your-server.example.com/ably-auth:

<?php
// ably-auth.php: serve this script at /ably-auth.
require __DIR__ . '/vendor/autoload.php';

use Ably\PubSub\Server;

$ablyApiKey = getenv('ABLY_API_KEY');
$client = Server::createHttpClient(['key' => $ablyApiKey]);

// Authenticate the caller first. Grant only the operations this user needs.
$userId = 'me'; // the signed-in user's ID, from your session
$tokenRequest = $client->auth->createTokenRequest([
    'clientId' => $userId,
    // Without a capability, the token gets all of the API key's capabilities.
    'capability' => ['test-channel' => ['publish', 'subscribe', 'history']],
]);

header('Content-Type: application/json');
echo json_encode($tokenRequest->toArray());

See token authentication for how devices use it.

On Laravel, use the Laravel broadcaster instead: it issues tokens to Ably's fork of Laravel Echo from Laravel's /broadcasting/auth route.

Migrating from 1.x

Version 2.0 renames the package and namespace, and creates clients with a factory method.

	1.x	2.0
Package	ably/ably-php	ably/pubsub-server
Namespace	Ably\	Ably\PubSub\
HTTP client	new AblyRest($options)	Server::createHttpClient($options)

See UPDATING.md for all other changes.

Common configuration

Server::createHttpClient() takes an options array or an Ably\PubSub\Models\ClientOptions object.

Endpoint

endpoint selects the Ably host for HTTP requests. It replaces the 1.x environment and restHost options. 2.0 ignores those options, so a client that still sets them connects to production.

$ablyApiKey = getenv('ABLY_API_KEY');
$client = Server::createHttpClient([
    'key' => $ablyApiKey,
    'endpoint' => 'nonprod:sandbox',
]);

• Never put a port in endpoint: localhost:8080 is not a hostname and does not resolve.
• Set the port with tlsPort, or with port when TLS is off.
• With TLS off ('tls' => false), use token authentication.

See UPDATING.md for how the old options map to endpoint.

Proxy

To send every request through a proxy, set http_proxy (or https_proxy) in $_SERVER. From the PHP command line, an environment variable does this. Put any proxy credentials in the URL:

export http_proxy=http://username:password@proxy.example.com:8080

Logging

Set logLevel to Log::NONE, Log::ERROR, Log::WARNING (the default), Log::DEBUG or Log::VERBOSE. Logs go to standard output. To handle them yourself, set logHandler:

use Ably\PubSub\Log;
use Ably\PubSub\Server;

$ablyApiKey = getenv('ABLY_API_KEY');
$client = Server::createHttpClient([
    'key' => $ablyApiKey,
    'logLevel' => Log::DEBUG,
    'logHandler' => function ($level, $args) {
        error_log('Ably: ' . json_encode($args));
    },
]);

Logging settings are global: the most recently created client sets them for the whole process.

Platform notes

Laravel

The current releases of Ably's Laravel broadcaster and Laravel SDK depend on ably/ably-php 1.x, not on ably/pubsub-server. See Getting started with Laravel.

Known limitations

• The SDK has no realtime client. It uses the Ably REST API only, so it can't subscribe to channels or enter presence.
• To receive messages in PHP, use Ably's MQTT adapter with an MQTT client such as Mosquitto-PHP.

Further reading

• Getting started with Pub/Sub using PHP
• Ably Pub/Sub documentation and examples
• Token authentication
• UPDATING.md: migrating from 1.x
• CHANGELOG.md: release notes; all Ably releases are listed on changelog.ably.com

Contributing

Read CONTRIBUTING.md before contributing.

Support, feedback and troubleshooting

For help, visit Ably's support page. Report bugs and compatibility problems on GitHub Issues.

License

Licensed under the Apache License, Version 2.0. See LICENSE.