dotenv-run-script

Run NPM scripts with changing environments.

Usage

Install the package

npm install dotenv-run-script --save-dev

Add one or more scripts to your package.json which uses one or more environment variables (GREETINGS in the example below)

{
  // ... other package stuff above
  "scripts": {
    "test": "echo $GREETING world!"
  }
}

Create an .env file with the variables used by the script

GREETING=Hello

npx dotenv-run-script test

Run the test NPM script.

Using multiple .env files

The dotenv-run-script CLI takes any number of optional positional arguments, one for each .env file to be loaded (in sequence).

The arguments are checked in sequence, all arguments will get parsed and expanded until either the argument -- or the argument does not resolve to a file.

The following loads a .env followed by a .env.production file and proceeds to execute the test script.

npx dotenv-run-script .env .env.production -- test

Adding a script per environment

It's recommended to add a script to the project's package.json to signal the use of dotenv-run-script and ease the discovery of supported environments:

{
  // ... other package stuff above
  "scripts": {
    "greet": "echo $GREETING $PLACE",
    "production": "dotenv-run-script .env .env.production --",
    "development": "dotenv-run-script .env .env.development --",
  }
}

// .env
GREETING=Hello
PLACE=World!

// .env.production
PLACE=Universe!

// .env.development
PLACE=Localhost

In the example above, two environments are used .env.production and .env.development in addition to a shared .env which includes common variables. Notice how the PLACE variable gets overridden.

The greet script can be invoked with

npm run production greet

Examples

See the simple and advanced examples for usage.

Alternatives you might consider using

• dotenv's preload script
• dotenv-run which provide similar, but limited functionality to this package. At the time of writing this, it does not
  • use dotenv-expand to assign variables from other variables.
  • allow multiple .env files to be loaded in sequence
  • call npm run but any executable