An experimental idea of an endpoint schema with translation logic

Schema

class MessageSchema extends EndpointSchema 
{
    public function bridge () {
        return [
            'message' => new Parameter([
                'get' => function($e) {
                    return $e->getMessage();
                }
                'set' => function($i, $e) {
                    return $e->setMessage($i);
                }
            ]),
            'destination' => new Parameter([
                'get' => function($e) {
                    return $e->getRecipient();
                }
                'set' => function($i, $e) {
                    return $e->setRecipient($i);
                }
            ]),
            'sender' => new Parameter([
                'set' => function($i, $e) {
                    return $e->setSender($i);
                }
            ]),
            'sent_at' => new Parameter([
                'get' => function($e) {
                    return $e->created_at;
                }
            ])
        ];
    }
}