The problem with REST endpoints and state -- reading a simple hierarchical novel

rest-endpoints-multiple-round-trips.js

class Reader extends React.Component {
  componentWillReceiveProps (nextProps) {
    const {
      entities: { novels, chapters, words },
      pagination: {
        novelsByContributor, chaptersByNovel, wordsByChapter
      }
    } = nextProps;

    const isFetchingChapters = chaptersByNovel[NOVEL_ID]
                               && chaptersByNovel[NOVEL_ID].isFetching;

    const requestChapters = !isFetchingChapters
                            && isEmpty(chapters)
                            && !isEmpty(novels);

    const isFetchingText = wordsByChapter[CHAPTER_ID]
                           && wordsByChapter[CHAPTER_ID].isFetching;

    const requestChapterText = !isFetchingText
                               && isEmpty(words)
                               && !isEmpty(chapters);

    if (requestChapters) {
      this.props.loadChapters(novels[NOVEL_ID]);
    }

    if (requestChapterText) {
      this.props.loadChapterText(chapters[CHAPTER_ID]);
    }
  }
}