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The Mercure Component

4.2 version

The Mercure Component

Mercure is an open protocol allowing to push data updates to web browsers and other HTTP clients in a convenient, fast, reliable and battery-friendly way. It is especially useful to publish real-time updates of resources served through web APIs, to reactive web and mobile applications.

The Mercure Component implements the “publisher” part of the Mercure Protocol.


$ composer require symfony/mercure


If you install this component outside of a Symfony application, you must require the vendor/autoload.php file in your code to enable the class autoloading mechanism provided by Composer. Read this article for more details.


The following example shows the component in action:

// change these values accordingly to your hub installation
define('HUB_URL', 'https://demo.mercure.rocks/hub');
define('JWT', 'eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJtZXJjdXJlIjp7InN1YnNjcmliZSI6WyJmb28iLCJiYXIiXSwicHVibGlzaCI6WyJmb28iXX19.LRLvirgONK13JgacQ_VbcjySbVhkSmHy3IznH3tA9PM');

use Symfony\Component\Mercure\Jwt\StaticJwtProvider;
use Symfony\Component\Mercure\Publisher;
use Symfony\Component\Mercure\Update;

$publisher = new Publisher(HUB_URL, new StaticJwtProvider(JWT));
// Serialize the update, and dispatch it to the hub, that will broadcast it to the clients
$id = $publisher(new Update('https://example.com/books/1.jsonld', 'Hi from Symfony!', ['target1', 'target2']));

Read the full Mercure integration documentation to learn about all the features of this component and its integration with the Symfony framework.

This work, including the code samples, is licensed under a Creative Commons BY-SA 3.0 license.