Configure axios to automatically set the Rails CSRF token

index.js

import axios from 'axios'

const tokenEl = document.getElementsByName('csrf-token')[0]
if (tokenEl) {
  const token = tokenEl.getAttribute('content')
  axios.defaults.headers.common['X-CSRF-Token'] = token
}
axios.defaults.headers.common['Accept'] = 'application/json'
axios.defaults.headers.post['Content-Type'] = 'application/json'