Axios 401 response interceptor.

axios-401-response-interceptor.js

// Add a 401 response interceptor
window.axios.interceptors.response.use(function (response) {
    return response;
}, function (error) {
    if (401 === error.response.status) {
        swal({
            title: "Session Expired",
            text: "Your session has expired. Would you like to be redirected to the login page?",
            type: "warning",
            showCancelButton: true,
            confirmButtonColor: "#DD6B55",
            confirmButtonText: "Yes",
            closeOnConfirm: false
        }, function(){
            window.location = '/login';
        });
    } else {
        return Promise.reject(error);
    }
});

axios401.js

const baseURL = localStorage.getItem('domain');
const defaultOptions = {
  baseURL,
  method: 'get',
  headers: {
    'Content-Type': 'application/json',
  }
};
// Create Instance
const axiosInstance = axios.create(defaultOptions);
// Get token from session
const accessToken = ...

// Set the auth token for any request
instance.interceptors.request.use(config => {
  config.headers.Authorization = accessToken ? `Bearer ${accessToken}` : '';
  return config;
});

// Last step: handle request error general case
instance.interceptors.response.use(
  response => response,
  error => {
    // Error
    const { config, response: { status } } = error;

    if (status === 401) {
      // Unauthorized request: maybe access token has expired!
      return refreshAccessToken(config);
    } else {
      return Promise.reject(error);
    }
  }
});