最后这是我实现的(仅用于演示目的 - 省略了无关代码):
eventRoot.js:
import { combineReducers } from 'redux'
import ranges from './events'
import ids from './ids'
import params from './params'
import total from './total'
export default resource =>
combineReducers({
ids: ids(resource),
ranges: ranges(resource),
params: params(resource)
})
events.js:
import { GET_EVENTS_SUCCESS } from '@/state/types/data'
export default resource => (previousState = {}, { type, payload, requestPayload, meta }) => {
if (!meta || meta.resource !== resource) {
return previousState
}
switch (type) {
case GET_EVENTS_SUCCESS:
const newState = Object.assign({}, previousState)
payload.data[resource].forEach(record => {
// ISO 8601 time interval string -
// http://en.wikipedia.org/wiki/ISO_8601#Time_intervals
const range = record.start + '/' + record.end
if (newState[record.id]) {
if (!newState[record.id].includes(range)) {
// Don't mutate previous state, object assign is only a shallow copy
// Create new array with added id
newState[record.id] = [...newState[record.id], range]
}
} else {
newState[record.id] = [range]
}
})
return newState
default:
return previousState
}
}
还有一个数据缩减器,但它链接在父级缩减器中,因为通用实现可重复用于常见列表响应。更新事件数据并删除开始/结束属性,因为它由范围 (ISO 8601 time interval string) 组成。这可以稍后由 moment.range 使用或由 '/' 拆分以获取开始/结束数据。我选择了范围字符串数组来简化对现有范围的检查,因为它们可能会变大。我认为在这种情况下,原始字符串比较(indexOf 或 es6 包括)会比在复杂结构上循环更快。
data.js(精简版):
import { END } from '@/state/types/fetch'
import { GET_EVENTS } from '@/state/types/data'
const cacheDuration = 10 * 60 * 1000 // ten minutes
const addRecords = (newRecords = [], oldRecords, isEvent) => {
// prepare new records and timestamp them
const newRecordsById = newRecords.reduce((prev, record) => {
if (isEvent) {
const { start, end, ...rest } = record
prev[record.id] = rest
} else {
prev[record.id] = record
}
return prev
}, {})
const now = new Date()
const newRecordsFetchedAt = newRecords.reduce((prev, record) => {
prev[record.id] = now
return prev
}, {})
// remove outdated old records
const latestValidDate = new Date()
latestValidDate.setTime(latestValidDate.getTime() - cacheDuration)
const oldValidRecordIds = oldRecords.fetchedAt
? Object.keys(oldRecords.fetchedAt).filter(id => oldRecords.fetchedAt[id] > latestValidDate)
: []
const oldValidRecords = oldValidRecordIds.reduce((prev, id) => {
prev[id] = oldRecords[id]
return prev
}, {})
const oldValidRecordsFetchedAt = oldValidRecordIds.reduce((prev, id) => {
prev[id] = oldRecords.fetchedAt[id]
return prev
}, {})
// combine old records and new records
const records = {
...oldValidRecords,
...newRecordsById
}
Object.defineProperty(records, 'fetchedAt', {
value: {
...oldValidRecordsFetchedAt,
...newRecordsFetchedAt
}
}) // non enumerable by default
return records
}
const initialState = {}
Object.defineProperty(initialState, 'fetchedAt', { value: {} }) // non enumerable by default
export default resource => (previousState = initialState, { payload, meta }) => {
if (!meta || meta.resource !== resource) {
return previousState
}
if (!meta.fetchResponse || meta.fetchStatus !== END) {
return previousState
}
switch (meta.fetchResponse) {
case GET_EVENTS:
return addRecords(payload.data[resource], previousState, true)
default:
return previousState
}
}
这可以被带有事件选择器的日历组件使用:
const convertDateTimeToDate = (datetime, timeZoneName) => {
const m = moment.tz(datetime, timeZoneName)
return new Date(m.year(), m.month(), m.date(), m.hour(), m.minute(), 0)
}
const compileEvents = (state, filter) => {
const eventsRanges = state.events.list.ranges
const events = []
state.events.list.ids.forEach(id => {
if (eventsRanges[id]) {
eventsRanges[id].forEach(range => {
const [start, end] = range.split('/').map(d => convertDateTimeToDate(d))
// You can add an conditional push, filtered by start/end limits
events.push(
Object.assign({}, state.events.data[id], {
start: start,
end: end
})
)
})
}
})
return events
}
这是数据结构在 redux 开发工具中的样子:
每次获取事件时,都会更新其数据(如果有更改)并添加引用。这是获取新事件范围后redux diff的屏幕截图:
希望这对某人有所帮助,我只是补充一点,这还没有经过实战测试,而是更多地证明了一个有效的概念。
[编辑]顺便说一句。我可能会将其中一些逻辑移至后端,因为这样就不需要拆分/加入/删除属性。