redux-effects-example2.js

// Fetch results when:
// - page is changed (immediately after):
// - "sort by" filter is changed (immediately after),
// - search query is changed (after 500 ms debounce),
// - filters are changed (after 300 ms debounce)
const refetchResultsEpic = action$ => {
  return Observable.merge(
    action$.ofType(CHANGE_QUERY).debounceTime(500),
    action$.ofType(CHANGE_FILTERS).debounceTime(300),
    action$.ofType(CHANGE_PAGE),
    action$.ofType(CHANGE_SORT_BY),
  )
  .mapTo({ type: FETCH_RESULTS });
}