How to access env vars from webpack.config.js file?

Question

I try to access env vars from webpack.config.js through process.env.env_name, although i've access to env vars in my .env (locally) through process.env.env_name in webpack.config.js, i can't access env vars declared in config/default.js file. any idea? –

Answer 1

You can use webpack.DefinePlugin like this

plugins: [
        new webpack.DefinePlugin({
            'process.env': {
                'NODE_ENV': JSON.stringify('development'),
                'BASE_URL': JSON.stringify('http://localhost:5000/')
            }
        })
    ],

Then read in your js code like this

 process.env.BASE_URL

Answer 2

Option 1 - Variables on webpack file

You can pass in your env variables on the script:

webpack --env.MY_VARIABLE=VALUE --env.MY_OTHER_VARIABLE=OTHER_VALUE

and access it:

...

module.exports = env => {
  // Use env.<YOUR VARIABLE> here:
  console.log('MY_VARIABLE: ', env.MY_VARIABLE); // 'VALUE'
  ...
};

---

Option 2 - Variables on your app

Or you can read it from your env file using some package, like dotenv.

run npm i dotenv.

Import it on your webpack.config.js file:

// if .env is on same folder as webpack.config.js
var dotenv = require('dotenv')

// if is located elsewhere
var dotenv = require('dotenv').config({ path: '/full/custom/path/to/your/env/vars' });

// same as above, but with abstraction
var dotenv = require('dotenv').config({path: __dirname + '/.env'});

And finally:

// define a new plugin on your webpack
plugins: [
    ...
    new webpack.DefinePlugin({

        // try:
        "process.env": dotenv.parsed

        // or:
        'process.env': JSON.stringify(dotenv.config().parsed)
    }),
]

Now you can read your variables inside your app as process.env.MY_VARIABLE, defined in .env.