Get the name of controller, from JS

app|assets|javascripts|hoge.js

getControllerName() {
  // Ex) DOMAIN.com/NAME_SPACE/CONTROLLER_NAME/ACTION
  
  var pathname = window.location.pathname;  // /NAME_SPACE/CONTROLLER_NAME/ACTION
  let splitedPathnames = pathname.replace(/\//, '');  // [ 'NAME_SPACE', 'CONTROLLER_NAME', 'ACTION' ]
  return splitedPathnames.split('/')[1];  // CONTROLLER_NAME
}