apollo/services/trackers/aggregate-tracker.js

class AggregateTracker {
  #trackers = []

  constructor(trackers) {
    this.#trackers = trackers;
  }

  async poll() {
    let media = []
    for (let tracker of this.#trackers)
      media = media.concat(await tracker.poll());

    return media;
  }
}

module.exports = AggregateTracker;