node 生成 cli 實戰

又在寫bug發表於2018-11-16

前言

本文主要重點在於實戰程式碼，原理性的東西相信大家都能在其他地方搜到就不講了

程式碼部分

工程目錄

package.json

可以直接負責，也可以 npm init 。但是其中 bin 語句必不可少下面會講解到

{
"name": "webpack4_cli_yhy",
"version": "1.0.2",
"description": "test-cli",
"main": "./index.js",
"keywords": [
  "cli"
],
"bin": {
  "webpack4-cli": "./index.js"
},
"scripts": {
  "test": "echo \"Error: no test specified\" && exit 1"
},
"author": "",
"license": "ISC",
"dependencies": {
  "chalk": "^2.4.1",
  "commander": "^2.19.0",
  "download-git-repo": "^1.1.0",
  "handlebars": "^4.0.12",
  "inquirer": "^6.2.0",
  "log-symbols": "^2.2.0",
  "ora": "^3.0.0"
}
}

複製程式碼

index.js

#!/usr/bin/env node
const fs = require('fs');
const program = require('commander');
const download = require('download-git-repo');
const handlebars = require('handlebars');
const inquirer = require('inquirer');
const ora = require('ora');
const chalk = require('chalk');
const symbols = require('log-symbols');

program.version('1.0.0', '-v, --version')
   .command('init <name>')
   .action((name) => {
       if(!fs.existsSync(name)){
           inquirer.prompt([
               {
   				name: 'description',
   				message: '請輸入專案描述'
   			},
   			{
   				name: 'author',
   				message: '請輸入作者名稱'
   			}
           ]).then((answers) => {
               const spinner = ora('正在下載模板...');
               spinner.start();
   			download('yuhaiyang1/webpack4', name, (err) => {
                   if(err){
                       spinner.fail();
                       console.log(symbols.error, chalk.red(err));
                   }else{
                       spinner.succeed();
                       const fileName = `${name}/package.json`;
                       const meta = {
                           name,
                           description: answers.description,
                           author: answers.author
                       }
                       if(fs.existsSync(fileName)){
                           const content = fs.readFileSync(fileName).toString();
                           const result = handlebars.compile(content)(meta);
                           fs.writeFileSync(fileName, result);
                       }
                       console.log(symbols.success, chalk.green('專案初始化完成'));
                   }
               })
           })
       }else{
           // 錯誤提示專案已存在，避免覆蓋原有專案
           console.log(symbols.error, chalk.red('專案已存在'));
       }
   })
program.parse(process.argv);
複製程式碼