javascript - Environment variables - undefined - Stack Overflow

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I want to use environment variables. I made a custom react app environment.

Everything is ok, the app runs properly, no errors. But the variables from .env file gives undefined and the process.env gives an empty object.

I added dotenv and REACT_APP prefix to the variable.

And in webpack.config.js file i added node: { fs: 'empty' }, from here

Here are my configurations.

Folder structure:

I want to use environment variables. I made a custom react app environment.

Everything is ok, the app runs properly, no errors. But the variables from .env file gives undefined and the process.env gives an empty object.

I added dotenv and REACT_APP prefix to the variable.

And in webpack.config.js file i added node: { fs: 'empty' }, from here

Here are my configurations.

Folder structure:

• javascript
• node.js
• reactjs
• webpack
• environment-variables

Share Follow edited Dec 4, 2019 at 4:15 Tony 20.2k77 gold badges4141 silver badges6262 bronze badges asked Dec 3, 2019 at 10:14 user11910832user11910832 7

• try npmjs./package/dotenv to use .env variables – Harish Commented Dec 3, 2019 at 10:16
• Added dotenv same result. – user11910832 Commented Dec 3, 2019 at 10:17
• REACT_APP prefix is a feature of create-react-app cli, not of react. try this: npmjs./package/dotenv-webpack – Murli Prajapati Commented Dec 3, 2019 at 10:33
• 1 @grecdev A very good article in setting up .env file for react server-side as well as for client-side app. medium./@trekinbami/… – Darpan Rangari Commented Dec 3, 2019 at 10:35
• @grecdev Also I can see you are not using any parameter after --env in your start script this might override all the variable defined in .env file, either use --env in the script or use .env file. – Darpan Rangari Commented Dec 3, 2019 at 10:41

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4 Answers 4

Sorted by: Reset to default 2

PROBLEM SOLVED:

1. Uninstall dotenv
2. Remove these two from main app.js file:

const dotenv = require('dotenv')
dotenv.config();

3. Remove the flag --env from npm start script.

4. Remove node: { fs: 'empty' } from webpack.config.js file

5. Install dotenv-webpack, and follow the instructions from there.

No need for REACT_APP prefix.

Fixed configuration files

You have to put REACT_APP in front of the variable name you want to have

eg:/

REACT_APP_YOUR_VAR="something"

You don't need to install Dotenv or something else, because React has its own.

try https://www.npmjs./package/dotenv to use .env variables

In your entry JS file add below code snippet (maybe your ./src/assets/js/app.js)

const dotenv = require('dotenv')
dotenv.config()

and restart your app.

You can use webpack.DefinePlugin

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

Then in your code simply use process.env.NODE_ENV to access ENV variable

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