reactjs - How to use environment variables in Github Page?

Question

I want to deploy my create-react-app project to GitHub Pages. But I have a few secret keys. How can I manage these keys inside my React app?

Answer 1

Edited June 2020

Reference @alicia-jasmine

"React is purely a front-end framework. Everything accessible to React (even if you embed it through a build step) will later be visible in the front-end code and someone relatively basic to find. To really keep them secret you MUST have something server side!"

The following answer will actually expose the key in the gh-page branch on GitHub, also the keys will be accessible through the network tab in the developer console.

Original Answer

I'm also using create-react-app, and I found that this can be done by customizing your CI script with GitHub secret settings. (After the setting, you can use environment variables like this in your project.)

const apiKey = process.env.REACT_APP_APIKey
const apiSecret = process.env.REACT_APP_APISecret

To add a secret to your repository, go to your repository's Setting > Secrets, click on Add a new secret. In the screenshot below, I added 2 env variables: REACT_APP_APIKey and REACT_APP_APISecret.

Notice: All the environment variable you want to access with create-react-app need to be prefixed with REACT_APP.

After you have your secret ready, you can take a look at this post, it's about how to add your own Action upon push.

To setup your action script, go to your repository > Actions, an click on Setup workflow your self, and paste in the script provided in the post or take a look at mine script below.

I use the following script to access the 2 environment variables I set on GitHub secret. (You can access the secret you set in the script by ${{ secrets.REACT_APP_APIKey }}.)

name: CI

on:
  push:
    branches:
      - master

jobs:
  build:

    runs-on: ubuntu-latest

    steps:
    
    - name: Checkout
      uses: actions/checkout@v1

    - name: Build
      run: |
        npm install
        npm run-script build
      env:
        REACT_APP_APIKey: ${{ secrets.REACT_APP_APIKey }}
        REACT_APP_APISecret: ${{ secrets.REACT_APP_APISecret }}

    - name: Deploy
      uses: JamesIves/github-pages-deploy-action@releases/v3
      with:
        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        BRANCH: gh-pages
        FOLDER: build

After you setup the script, the action will be triggered by any push to master branch. After you push any commits, you can take a look at the deployment status at actions status.

You can see how hard it is for me to figure it out... so many fail attempts lol. Anyway, hope this will help :)