common.js

// 动态测速选择的域名
// h5直接返回默认第一个域名
// vue文件用到域名的话用this.$baseURL
let domains = [{uri:'192.168.31.215:9523', speed:0},{uri:'api.ceshi.org', speed:0},
]export const protocol = {api: 'http://',//本地// api: 'https://api.',//正式h5Url: 'https://www.',//正式downAPPUrl: 'https://download.'//正式
}export async function getDomain(){const result = new Promise((resolve, reject)=>{testSpeed().then(res=>{resolve(res)}).catch(()=>{resolve(domains[0].uri)})})return result
}// 得出最快的域名
// speedTest.jpg 需要提前放到服务器上，根据图片的访问速度来选择请求的接口
function testSpeed(){return new Promise((resolve, reject)=>{let array = []domains.forEach((item, index) => {array.push(getSpeedWithAjax(`${protocol.api}${item.uri}/images/speedTest.jpg`))})Promise.all(array).then(res=>{console.log(res);domains.forEach((e,i)=>{e.speed = res[i]})let arr = sort_uris(domains)resolve(arr[0].uri)}).catch((err)=>{console.log(err);reject()})})}
// 测速后排序数组
function sort_uris(array) {let compare = function(obj1, obj2) {var val1 = obj1.speed;var val2 = obj2.speed;if (val1 < val2) {return -1;} else if (val1 > val2) {return 1;} else {return 0;}}return array.filter((num) => {return num.speed > 0;}).sort(compare)
}function getSpeedWithAjax(url){return new Promise((resolve, reject) => {let start = null;let end = null;start = new Date().getTime();const xhr = uni.request({url,timeout:2000,success: () => {end = new Date().getTime();resolve(end - start)},fail: () => {resolve(0)}});})
}

main.js

import { getDomain, protocol } from '@/utils/common.js' //公共方法
getDomain().then(domain=>{console.log(domain);// H5地址let h5Url = `${protocol.h5Url}${domain}`// APP下载地址let downAPPUrl = `${protocol.downAPPUrl}${domain}`// 接口let baseUrl = `${protocol.api}${domain}`uni.$emit('urlChange',{baseUrl})Object.assign(Vue.prototype, {'$downAPPUrl':downAPPUrl,'$h5Url':h5Url,'$imgUrl':baseUrl,})const app = new Vue({...App,i18n})app.$mount()
})

request.js

let baseURL;
uni.$on('urlChange',data=>{baseURL = data.baseUrl
})
// 这个baseURL  就是根据图片访问速度 动态获取到的接口url
console.log(baseURL)