const parseArgs = require('minimist'); const fs = require('fs'); const assert = require('assert'); class MyDoc { constructor() { this.workDir = './'; } async init() { await this.convert(); } async convert() { this.env = fs.readFileSync(`${this.workDir}env.json`, 'utf8'); let data = ` { console.log(item); }); } } (new MyDoc).init();