url retry

 需求是某些地區只能打domain，有些地區只能打ip，所以pm要求我寫一個retry的功能，當一個不通在打另外一個

export const orderPostRetryHandler = async (callApi) => {

return retryHandler(callApi, [

{ baseUrl: "url1", maxTimes: 2 },

{ baseUrl: "url2", maxTimes: 2 },

])

}

export const retryHandler = (callApi, retrySettings) => {

let tryTimes = 1

let index = 0

const tryFunc = async () => {

const { baseUrl, maxTimes } = retrySettings[index]

try {

const res = await callApi(baseUrl)

if (res.status == -1) {

throw res

}

return res

} catch (e) {

tryTimes++

if (tryTimes > maxTimes) {

if (++index >= retrySettings.length) {

throw e

}

tryTimes = 1

}

return tryFunc()

}

}

return tryFunc()

}

但這有個問題，就是等打了兩遍都打不通時間都過去十秒了，真的有人願意等這麼久嗎？所以我突發奇想，為什麼不兩個網址都打，哪個通就走哪個，所以我又改成以下

export const urlChecker = (urls) => {

let passUrl = ""

return async () => {

if (passUrl) return passUrl

const res = await Promise.any(urls.map((url) => fetch(url)))

passUrl = res.url

return passUrl

}

}

const getActivatedUrl = await urlChecker("url1", "url2")

fetch(`${await getActivatedUrl()}/api/`)

這樣體驗好多了

1/19調整一下，如果使用any回來的是無效網址那就會壞掉
所以須改用Promise.all(urls.map(url => axios.get(url, {timeout: 3000})).then(urls => urls.filter(x =>x)[0])