[ENHANCEMENT] Implement `--env-file` option in npm-run-script

[pereorga]

See equivalent Node.js option in https://nodejs.org/dist/latest-v20.x/docs/api/cli.html#--env-fileconfig

Related: nodejs/node#49514

[ljharb]

There’s no need; set NODE_OPTIONS to contain that node option.

[bengunnewijkGeonovum]

Based on @ljharb's comment that it should work with just setting NODE_OPTIONS I expected method 1 and 2 to work, but it only worked with method 3.

// Method 1
{
  ...,
  "scripts": {
    "build": "set NODE_OPTIONS='--env-file=.env' && webpack --config webpack.config.js"
  },
  ...
}

Another method I expected to work but didn't:

// Method 2
set NODE_OPTIONS='--env-file=.env'
npm run build

The method that ended up working for me, thank you meduzen in nodejs/node#49514

// Method 3
{
  ...,
  "scripts": {
    "build": "node --env-file=.env node_modules/webpack/bin/webpack --config webpack.config.js"
  },
  ...
}

In webpack.config.js I have two console logs:
console.log("A .env value:");
console.log(process.env.MY_VAR);

[PaperStrike]

@pereorga @ljharb Did NODE_OPTIONS work? I am getting: --env-file= is not allowed in NODE_OPTIONS. It's not listed in the documentation.

[penx]

There’s no need; set NODE_OPTIONS to contain that node option.

@ljharb can this be reopened? As per comments above, this is not an option. In latest node LTS (20.11.1) and current (21.7.1) you get

node: --env-file is not allowed in NODE_OPTIONS

Also see

• Add a feature to parse .env file by default nodejs/node#51413
• src: add process.loadEnvFile and util.parseEnv nodejs/node#51476

Now that process.loadEnvFile and util.parseEnv are available, perhaps this can be implemented as a cli flag in npx?

[lucasdonato]

up

[ericgopak]

up 👍

[checkmatez]

It can be useful to run a single npm script both locally and in CI/CD, where the CI/CD environment variables are injected automatically, while local variables are loaded from the .env file:

"test:db": "jest db.test.js",

Now you can run it locally: npm run --env-file=.env test:db while in CI/CD you would use a built-in mechanism for passing environment variables to scripts and run it simply with "npm run test:db".

[40detectives]

In the meantime, what’s the recommended way to do this?
Are npm scripts stuck with third-party dependencies to read env vars?