@rails/webpacker/package/env.js

Use webpack to manage app-like JavaScript modules in Rails

const { safeLoad } = require('js-yaml')
const { readFileSync } = require('fs')

const NODE_ENVIRONMENTS = ['development', 'production', 'test']
const DEFAULT = 'production'
const configPath = require('./configPath')

const railsEnv = process.env.RAILS_ENV
const nodeEnv = process.env.NODE_ENV

const config = safeLoad(readFileSync(configPath), 'utf8')
const availableEnvironments = Object.keys(config).join('|')
const regex = new RegExp(`^(${availableEnvironments})$`, 'g')

module.exports = {
  railsEnv: railsEnv && railsEnv.match(regex) ? railsEnv : DEFAULT,
  nodeEnv: nodeEnv && NODE_ENVIRONMENTS.includes(nodeEnv) ? nodeEnv : DEFAULT
}