Api_root for multiple environment backend apis.

api.config.js

let backendHost;

const hostname = window && window.location && window.location.hostname;

if(hostname === 'localhost') {
  backendHost = 'http://localhost:5000'; //when frontend and backend are on the same server
} else if(hostname === 'yourWebsitename') { //eg markde.netlify.com
  backendHost = 'backend_server_address';  //for backend hosted on different server not same as frontend
} else{
  backendHost = '';
}

export const API_ROOT = `${backendHost}`