Angular error interceptors

API.service.js

export class APIService {
  constructor(Restangular, ToastService) {
    'ngInject';

    var headers = {
      'Content-Type': 'application/json',
      'Accept': 'application/x.laravel.v1+json'
    };

    return Restangular.withConfig(function(RestangularConfigurer) {

      RestangularConfigurer
        .setBaseUrl('/api/')
        .setDefaultHeaders(headers)
        .setErrorInterceptor(function(response) {

          if (response.status === 422) {
            for (var error in response.data.errors) {
              var error_message = response.data.errors[error][0];
              return ToastService.error(error_message);
            }
          }

        });
    });
  }
}