---
title: "Besked K\x0f8"
image: /images/user-guide/emails/emails_header.png
---
Køer muliggør asynkrone operationer. De kan bruges til at udf�0F8re baggrundsopgaver, som for eksempel at sende en velkomstmail ved registrering.
Hver anvendelsestilf�0E6lde vil have sin egen k�0F8klasse, der udvides fra `MessageQueueServiceBase`.
I �F8jeblikket st�0Ftter vi kun `bull-mq`[bull-mq](https://bullmq.io/) som k�0F�1F er-driver.
## Trin til at oprette og bruge en ny kø
1. Tilf�0Fj et k�0F�F8navn til din nye k�0F�F8 under enum `MESSAGE_QUEUES`.
2. Provide the factory implementation of the queue with the queue name as the dependency token.
3. Inject the queue that you created in the required module/service with the queue name as the dependency token.
4. Add worker class with token based injection just like producer.
### Eksempel p�0E5 anvendelse
```ts
class Resolver {
constructor(@Inject(MESSAGE_QUEUES.custom) private queue: MessageQueueService) {}
async onSomeAction() {
//business logic
await this.queue.add(someData);
}
}
//async worker
class CustomWorker {
constructor(@Inject(MESSAGE_QUEUES.custom) private queue: MessageQueueService) {
this.initWorker();
}
async initWorker() {
await this.queue.work(async ({ id, data }) => {
//worker logic
});
}
}
```