// A service which transcodes video files
class VideoTranscoderService {

  private jobQueue: JobQueue<{ videoId: string; }>;

  onModuleInit() {
    // The JobQueue is created on initialization
    this.jobQueue = this.jobQueueService.createQueue({
      name: 'transcode-video',
      concurrency: 5,
      process: async job => {
        try {
          const result = await this.transcodeVideo(job.data.videoId);
          job.complete(result);
        } catch (e) {
          job.fail(e);
        }
      },
    });
  }

  addToTranscodeQueue(videoId: string) {
    this.jobQueue.add({ videoId, })
  }

  private transcodeVideo(videoId: string) {
    // e.g. call some external transcoding service
  }

}

class JobQueueService implements OnApplicationBootstrap, OnModuleDestroy {
  constructor(configService: ConfigService, processContext: ProcessContext)
  createQueue(options: CreateQueueOptions<Data>) => JobQueue<Data>;
  getJob(id: ID) => Promise<Job | undefined>;
  getJobs(options?: JobListOptions) => Promise<PaginatedList<Job>>;
  getJobsById(ids: ID[]) => Promise<Job[]>;
  getJobQueues() => GraphQlJobQueue[];
  removeSettledJobs(queueNames: string[], olderThan?: Date) => ;
  async cancelJob(jobId: ID) => ;
}