MessageInterface

Raxos\Contract\MessageBus\MessageInterface is the contract every message dispatched through raxos/message-bus implements, whether it is handled directly or placed on a queue.

Signature

interface MessageInterface extends SerializableInterface {}

The interface adds no members of its own. It exists purely as a marker on top of SerializableInterface.

Notes

• Extending SerializableInterface means a message must implement __serialize() and __unserialize(), so it can be put on a queue and restored later, even when it is dispatched directly and never actually queued.
• One HandlerInterface implementation is written per message type, matched by the concrete MessageInterface class the message implements.
• Messages are typically linked to their handler with raxos/message-bus's #[Handler] attribute.

Example

<?php
declare(strict_types=1);

namespace App\MessageBus\Message;

use Override;
use Raxos\Contract\MessageBus\MessageInterface;
use Raxos\DateTime\DateTime;

final readonly class SendWelcomeEmail implements MessageInterface
{
    public function __construct(
        public string $userId,
        public DateTime $requestedAt = new DateTime(),
    ) {}

    #[Override]
    public function __serialize(): array
    {
        return [$this->userId, $this->requestedAt->toIso8601String()];
    }

    #[Override]
    public function __unserialize(array $data): void
    {
        $this->userId = $data[0];
        $this->requestedAt = DateTime::parse($data[1]);
    }
}

See HandlerInterface for the matching handler contract.