Live updates

The players' screens follow a game as it is played: the squares the host calls, the cards that win, and, on a convention's card, the squares a gesture ticks. Mercure\BingoPublisher pushes them through Mercure, as private updates that name the game, the card's serial, the square and the pattern, never a player: each screen that hears an update reads what it may show from the application, with its own rights. It is optional, and needs symfony/mercure:

composer require symfony/mercure

Wiring the publisher

use Tilttek\Bingo\Mercure\BingoPublisher;

$publisher = new BingoPublisher(
    $hub,                                   // Symfony\Component\Mercure\HubInterface
    'https://example.com/bingo/games/',     // the topic prefix; the game's identifier follows it
);

In a Symfony application, register them on the event dispatcher:

# config/services.yaml
Tilttek\Bingo\Mercure\BingoPublisher:
    arguments: ['@mercure.hub.default', '%env(BINGO_TOPIC_PREFIX)%']
    tags:
        - { name: kernel.event_listener, event: Tilttek\Bingo\Event\SquareCalled, method: squareCalled }
        - { name: kernel.event_listener, event: Tilttek\Bingo\Event\BingoWon, method: bingoWon }
        - { name: kernel.event_listener, event: Tilttek\Bingo\Event\SquareTicked, method: squareTicked }

Subscribing

topic($game) gives the topic of a game, the prefix followed by its identifier encoded for a URL, and cardTopic($game, $serial) the topic of one card, the game's topic followed by / and the serial. The updates are private: the application gives each player a subscriber token for the game's topic and for their own card's topic only, once it checked that the card is theirs. A screen that hears an update reads the card again from the application; it never ticks a cell by itself.

The publisher keeps nothing between two calls: one instance serves every request of a worker.