React

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Injecting Variables At Build Time

React recognizes either environment variables or variables defined in a .env file located at the project root. React only recognizes variables which begin with REACT_APP_

export REACT_APP_SERVER_URL="www.myserver.com/api"

Environment variables take precedence over those defined in the .env file.

Imported variables are available in the React environment under process.env:

console.log(process.env.REACT_APP_SERVER_URL)
// stdout: www.myserver.com/api