env.js

const fs = require("fs");
const path = require("path");
const dotenv = require("dotenv");
const paths = require("./config");

delete require.cache[require.resolve("./config")];

if (!process.env.NODE_ENV) {
  throw new Error(
    "The process.env.NODE_ENV environment variable is required but was not specified."
  );
}

// https://github.com/bkeepers/dotenv#what-other-env-files-can-i-use
const dotenvFiles = [
  `${paths.dotenv}.${process.env.NODE_ENV}.local`,
  `${paths.dotenv}.${process.env.NODE_ENV}`,
  process.env.NODE_ENV !== "test" && `${paths.dotenv}.local`,
  paths.dotenv,
].filter(Boolean);

dotenvFiles.forEach((dotenvFile) => {
  if (fs.existsSync(dotenvFile)) {
    dotenv.config({
      path: dotenvFile,
    });
  }
});

const appDirectory = fs.realpathSync(process.cwd());
process.env.NODE_PATH = (process.env.NODE_PATH || "")
  .split(path.delimiter)
  .filter((folder) => folder && !path.isAbsolute(folder))
  .map((folder) => path.resolve(appDirectory, folder))
  .join(path.delimiter);

module.exports = () => {
  const raw = {
    PORT: process.env.PORT || 3001,
    NODE_ENV: process.env.NODE_ENV || "development",
  };

  // Stringify all values so we can feed into Webpack DefinePlugin
  const stringified = {
    "process.env": Object.keys(raw).reduce((env, key) => {
      env[key] = JSON.stringify(raw[key]);
      return env;
    }, {}),
  };

  return { raw, stringified };
};