Take you step by step to develop a node switching source gadget

npm config set registry  源地址

npm config get registry

{
    "npm": {
        "home": "https://www.npmjs.org",
        "registry": "https://registry.npmjs.org/",
        "ping": "https://registry.npmjs.org"
    },
    "yarn": {
        "home": "https://yarnpkg.com",
        "registry": "https://registry.yarnpkg.com/",
        "ping": "https://registry.yarnpkg.com"
    },
    "tencent": {
        "home": "https://mirrors.cloud.tencent.com/npm/",
        "registry": "https://mirrors.cloud.tencent.com/npm/",
        "ping": "https://mirrors.cloud.tencent.com/npm"
    },
    "cnpm": {
        "home": "https://cnpmjs.org",
        "registry": "https://r.cnpmjs.org/",
        "ping": "https://r.cnpmjs.org"
    },
    "taobao": {
        "home": "https://npmmirror.com",
        "registry": "https://registry.npmmirror.com/",
        "ping": "https://registry.npmmirror.com"
    },
    "npmMirror": {
        "home": "https://skimdb.npmjs.com/",
        "registry": "https://skimdb.npmjs.com/registry/",
        "ping": "https://skimdb.npmjs.com/registry"
    }
}

#!/usr/bin/env node

const { program } = require('commander')
const PKG = require('../package.json') //引入package json
const registries = require('../registries.json'); //引入初始源
const inquirer = require('inquirer');
const { exec, execSync } = require('child_process') //子线程用于执行shell命令
const ping = require('node-http-ping') //ping网址的一个库
const fs = require('fs')
const chalk = require("chalk"); //console 变颜色的一个库
const path = require('path')
program.version(PKG.version) //设置版本默认命令 -V --version

//读取源地址方便设置*
const getOrigin = async () => {
    return await execSync('npm get registry', { encoding: "utf-8" })
}

//列出所有的源，如果当前有在使用前面加上*
program.command('ls').description('查看镜像').action(async () => {

    const res = await getOrigin()

    const keys = Object.keys(registries)

    const message = []

    //填充横线算法npm------  yarn------
    const max = Math.max(...keys.map(v => v.length)) + 3
    keys.forEach(k => {

        const newK = registries[k].registry == res.trim() ? ('* ' + k) : ('  ' + k)
        const Arr = new Array(...newK)
        Arr.length = max;
        const prefix = Array.from(Arr).map(v => v ? v : '-').join('')

        message.push(prefix + '  ' + registries[k].registry)
    })
    console.log(message.join('\n'))
})

//切换源
program.command('use').description('请选择镜像').action(() => {
    inquirer.prompt([
        {
            type: "list",
            name: "sel",
            message: "请选择镜像",
            choices: Object.keys(registries)
        }
    ]).then(result => {

        const reg = registries[result.sel].registry

        exec(`npm config set registry ${reg}`, null, (err, stdout, stderr) => {

            if (err) {
                console.error('切换错误', err)
            } else {
                console.log('切换成功')
            }
        })
    })
})



//获取当前源
program.command('current').description('查看当前源').action(async () => {
    const reg = await getOrigin()
    const v = Object.keys(registries).find(k => {
        if (registries[k].registry === reg.trim()) {
            return k;
        }
    })
    console.log(chalk.blue('当前源:', v))
})

//ping 源
program.command('ping').description('测试镜像地址速度').action(() => {
    inquirer.prompt([
        {
            type: "list",
            name: "sel",
            message: "请选择镜像",
            choices: Object.keys(registries)
        }
    ]).then(result => {

        const url = registries[result.sel].ping.trim()

        ping(url).then(time => console.log(chalk.blue(`响应时长: ${time}ms`)))
            .catch(() => console.log(chalk.red('GG')))

    })
})

//添加源 读写registries.json 文件实现
program.command('add').description('自定义镜像').action(() => {
    inquirer.prompt([
        {
            type: "input",
            name: "name",
            message: "请输入镜像名称",
            validate(answer) {
                const keys = Object.keys(registries)
                if (keys.includes(answer)) {
                    return `不能起名${answer}跟保留字冲突`
                }
                if (!answer) {
                    return '名称不能为空'
                }
                return true
            }
        },
        {
            type: "input",
            name: "url",
            message: "请输入镜像地址",
            validate(answer) {
                if (!answer) {
                    return `url不能为空`
                }
                return true
            }       
        }
    ]).then(result => {

        const del = (url) => {
            const arr = url.split('')
            //本来想用at 16 以下不支持
            return arr[arr.length - 1] == '/' ? (arr.pop() && arr.join('')) : arr.join('')
        }

        registries[result.name] = {
            home: result.url.trim(),
            registry: result.url.trim(),
            ping: del(result.url.trim()), //去掉末尾/ 不然无法ping
        }
        fs.writeFileSync(path.join(__dirname, '../registries.json'), JSON.stringify(registries, null, 4))
        console.log(chalk.blue('添加完成'))
    })
})



program.parse(process.argv)

npm i xmzs -g

mmp ls

mmp use

mmp current

mmp ping

map add