Bullqueue blog - Queue Service

queue.service.ts

import { Queue } from 'bullmq';

enum Queues {
  DEFAULT = 'default',
}

export default class QueueService {
  private queues: Record<string, Queue>;
  private defaultQueue: Queue;

  private static instance: QueueService;

  private static QUEUE_OPTIONS = {
    defaultJobOptions: {
      removeOnComplete: false, // this indicates if the job should be removed from the queue once it's complete
      removeOnFail: false, // this indicates if the job should be removed from the queue if it fails
    },
    connection: {
      // redis server connection options
      host: process.env.REDIS_HOST,
      port: process.env.REDIS_PORT,
    },
  };

  constructor() {
    if (QueueService.instance instanceof QueueService) {
      return QueueService.instance;
    }

    this.queues = {};
    QueueService.instance = this;

    this.instantiateQueues();
  }

  async instantiateQueues() {
    this.defaultQueue = new Queue(Queues.DEFAULT, QueueService.QUEUE_OPTIONS);
    this.queues[Queues.DEFAULT] = this.defaultQueue;
  }

  getQueue(name: Queues) {
    return this.queues[name];
  }
}