awesome-compose/react-express-mongodb/backend/config/config.js

var env = process.env.NODE_ENV || 'development';

if(env === 'development' || env === 'test'){

    const config = require('./config.json')
    let envConfig = config[env];
    console.log(envConfig);

    Object.keys(envConfig).forEach((key) => {
        process.env[key] = envConfig[key]
    })
}