MessageSubscriberInterface

Returns a list of messages to be handled.

It returns a list of messages like in the following example:

yield MyMessage::class;

It can also change the priority per classes.

yield FirstMessage::class => ['priority' => 0];
yield SecondMessage::class => ['priority => -10];

It can also specify a method, a priority and/or a bus per message:

yield FirstMessage::class => ['method' => 'firstMessageMethod'];
yield SecondMessage::class => [
    'method' => 'secondMessageMethod',
    'priority' => 20,
    'bus' => 'my_bus_name',
];

The benefit of using yield instead of returning an array is that you can yield multiple times the same key and therefore subscribe to the same message multiple times with different options.

The __invoke method of the handler will be called as usual with the message to handle.