Youtube in React: perform channel request if needed

watch.js

/* ... */
import {SEARCH_LIST_RESPONSE, VIDEO_LIST_RESPONSE} from '../api/youtube-api-response-types';
/* ... */
function* fetchVideoDetails(responses, shouldFetchChannelInfo) {
  const searchListResponse = responses.find(response => response.result.kind === SEARCH_LIST_RESPONSE);
  const relatedVideoIds =  searchListResponse.result.items.map(relatedVideo => relatedVideo.id.videoId);

  const requests = relatedVideoIds.map(relatedVideoId => {
    return buildVideoDetailRequest.bind(null, relatedVideoId);
  });

  if (shouldFetchChannelInfo) {
    // we have to extract the video's channel id from the video details response
    // so we can load additional channel information.
    // this is only needed, when a user directly accesses .../watch?v=1234
    // because then we only know the video id
    const videoDetailResponse = responses.find(response => response.result.kind === VIDEO_LIST_RESPONSE);
    const videos = videoDetailResponse.result.items;
    if (videos && videos.length) {
      requests.push(buildChannelRequest.bind(null, videos[0].snippet.channelId));
    }
  }
  /* ... */
}