在 redux-saga 或 reducer 中处理下载的项目规范化？

Question

我从删除 API 中获得的数据不是我的应用程序可以处理的格式。我的 saga 下载数据。

谁应该处理规范化？

在使用规范化数据调度成功操作之前的 saga 本身？

或者路由器应该在建立新状态之前规范化日期吗？

编辑我选择在 saga 中规范化并保持 reducer 清洁。它只是用 activitiesUpdated 提供的新活动替换活动。

减速器

export default function account(state = ACCOUNT, action) {
  switch (action.type) {
    case "account/LOGIN_SUCCESS":
      const { access_token, user } = action
      return { ...state, user, access_token, authenticated: true, error: "" }
    case "account/LOGOUT_SUCCESS":
      return ACCOUNT
    case "account/LOGIN_ERROR":
      return { ...state, error: action.error }
    case "account/ACTIVITIES_UPDATED":
      return { ...state, activities: action.activities }
    default:
      return state
  }
}

那些是传奇故事：

function sortActivities(activities) {
  return action.activities.sort((a,b) => b.timestamp.localeCompare(a.timestamp))
}

function addInvoices(activities) {
  let lastYearMonth, invoiceItem
  return activities.reduce((state, item, index) => {
    const currentYearMonth = item.timestamp.substr(0,7)
    if (currentYearMonth != lastYearMonth) {
      lastYearMonth = currentYearMonth
      invoiceItem = {
        id: currentYearMonth,
        type: "invoice",
        parking: 0,
        rebates: 0,
        sum: 0,
        timestamp: currentYearMonth
      }
      state.push(invoiceItem)
    }
    const amount = Math.abs(Number(item.gross_amount))
    if (item.type == "parking") {
      invoiceItem.parking += amount
      invoiceItem.sum -= amount
    } else if (item.type == "rebate" || item.type == "surplus") {
      invoiceItem.rebates += amount
      invoiceItem.sum += amount
    }
    state.push(item)
    return state
  }, [])
}

function *getActivities(access_token) {
  console.info("fetch activities")
  try {
    const activities = yield call(getActivitiesAsync, access_token)
    console.info("activities fetched")
    yield put(activitiesUpdated(addInvoices(activities.sortActivities(activities))))
  } catch (error) {
  }
}

function *updateActivities() {
  while (true) {
    const { access_token } = yield take(LOGIN_SUCCESS)
    console.info("Calling getActivities")
    yield call(getActivities, access_token)
    while (true) {
      const {type } = yield take([REFRESH_ACTIVITIES, LOGOUT])
      if (type == LOGOUT) {
        break
      }
      yield call(getActivities, access_token)
    }
  }
}

当您想到 updateActivities 传奇中的双重 while 循环时？

另外

是否正确

yield take([REFRESH_ACTIVITIES, LOGOUT])

只是

的快捷方式

yield race[take(REFRESH_ACTIVITIES), take(LOGOUT)]

Answer 1

最终，在这种情况下，您可以自由地做任何对您有用的事情——没有一个比另一个更有说服力的理由。根据数据的结构，您最终可能会发现，在 saga 中执行此操作的代码会更少，因为您只将结果分开一次而不是两次（在关心数据的 2 个减速器中的每一个中一次）。但是这可能是也可能不是这种情况。我也喜欢在减速器中这样做的想法，因为减速器通常应该尽可能简单，而这个模型符合这一点。

但就像我说的，我认为没有一个强有力的普遍论据支持另一个。

Answer 2

您还可以使用 createSelector 进行数据规范化，以保持 sagas 清洁：

- Selectors can compute derived data, allowing Redux to store the minimal possible state.
- Selectors are efficient. A selector is not recomputed unless one of its arguments changes.
- Selectors are composable. They can be used as input to other selectors.

在 redux-saga 或 reducer 中处理下载的项目规范化？

Handle downloaded item normalization in redux-saga or reducer?

reactjs

redux

redux-saga