phpMQTT Documentation

To add phpMQTT to your project, use Composer to require the package. Note that the current version is specified using the @dev flag.

composer require bluerhinos/phpmqtt=@dev

To create a script that stays active and waits for incoming messages on subscribed topics, use a pattern similar to subscribe.php.

Important: This pattern is intended for command-line execution (CLI) and is not suitable for standard web requests (like PHP-FPM/Apache), as it is designed to run continuously.

$ php subscribe.php

To send a message to a specific topic, use the publish() method.

Execution Patterns:

• Web Request: If running as a standard web request, you can simply call $mqtt->connect(), $mqtt->publish(), and $mqtt->close().
• Long-running CLI Script: If the script is intended to stay alive, you must call $mqtt->proc() regularly to maintain the connection with the broker and handle background processing.

// For web requests
$mqtt->connect();
$mqtt->publish('topic', 'message');
$mqtt->close();

// For long-running CLI scripts
$mqtt->connect();
// ... inside a loop ...
$mqtt->proc();
$mqtt->publish('topic', 'message');

If you need to display a message on a website by fetching it upon request, use the $mqtt->subscribeAndWaitForMessage() method. This method subscribes to a topic and blocks execution until a message is received, which it then returns.

Tip: To ensure messages appear instantly when a user loads a page, consider using retained messages on the broker side.

$message = $mqtt->subscribeAndWaitForMessage('your/topic');