costSaga.js

function delay(duration) {
  const promise = new Promise(resolve => {
    setTimeout(() => resolve(true), duration)
  })
  return promise
}

function* getCost(successAction) {
  try {
    const { startLocation, endLocation, apiKey } = yield select()
    const data = yield call(
      getEstimation,
      apiKey,
      startLocation.latitude,
      startLocation.longitude,
      endLocation.latitude,
      endLocation.longitude
    )
    yield put(requestToUberMade())
    yield put(successAction(data))
  } catch (error) {
    yield put(uberEstimationRequestFailed(error))
  }
}

export function* lookForCostSaga() {
  yield* getCost(rideValidated)
  function* polling() {
    const { waitingTime, page } = yield select()
    if (page !== 'Chart') return

    const requestFrequency =
      Math.round(60 / (MAX_REQUEST_IN_HOUR / waitingTime)) * 1000
    yield* getCost(newEstimationReceived)
    yield call(delay, requestFrequency)
    yield* polling()
  }
  yield* polling()
}