// A service which transcodes video files
class VideoTranscoderService {

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

  async onModuleInit() {
    // The JobQueue is created on initialization
    this.jobQueue = await this.jobQueueService.createQueue({
      name: 'transcode-video',
      process: async job => {
        return await this.transcodeVideo(job.data.videoId);
      },
    });
  }

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

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

}

class JobQueueService implements OnModuleDestroy {
  constructor(configService: ConfigService, jobBufferService: JobBufferService)
  async createQueue(options: CreateQueueOptions<Data>) => Promise<JobQueue<Data>>;
  async start() => Promise<void>;
  addBuffer(buffer: JobBuffer<any>) => ;
  removeBuffer(buffer: JobBuffer<any>) => ;
  bufferSize(forBuffers: Array<JobBuffer<any> | string>) => Promise<{ [bufferId: string]: number }>;
  flush(forBuffers: Array<JobBuffer<any> | string>) => Promise<Job[]>;
  getJobQueues() => GraphQlJobQueue[];
}