httpInterceptorFactory to manage authentication token in header and redirection

index.config.js

(function() {
	'use strict';
	
  angular.module('engageAngularApp')
  	.config(httpInterceptor);
  		
	/** @ngInject */
	function httpInterceptor($httpProvider) {
		$httpProvider.interceptors.push('httpInterceptorFactory');
	}
})();

index.services.js

(function() {
	'use strict';
	
	angular.module('engageAngularApp')
		.factory('httpInterceptorFactory', httpInterceptorFactory);
		
	/** @ngInject */
	function httpInterceptorFactory($q, $rootScope, $timeout, localStorageService, $injector, $log) {
		return {
			// This method is called before $http sends the request to the backend, so you can modify the configurations and make other actions. This function receives the request configuration object as a parameter and has to return a configuration object or a promise. Returning an invalid configuration object or promise that will be rejected, will make the $http call to fail.
			'request': function (config) {
				// $rootScope.$broadcast('loading:show');
				config.headers = config.headers || {};
				var userToken = localStorageService.get('token');
				// var currentState = $injector.get('$state').current.name;


				if(userToken === null){
					config.headers.Auth = '666';
				} else {
					config.headers.Auth = userToken;
				}

				// $log.log('token: ' + userToken);
				config.headers.Accept = 'application/json, text/plain, */*';
				return config;
			},
			// This method is called right after $http receives the response from the backend, so you can modify the response and make other actions. This function receives a response object as a parameter and has to return a response object or a promise. The response object includes the request configuration, headers, status and data that returned from the backend. Returning an invalid response object or promise that will be rejected, will make the $http call to fail.
			'response': function(response) {
				if(response.status === 401 || response.status === 403) {
					$log.error(response.status);
					$injector.get('$state').transitionTo('login');
				}
				// $rootScope.$broadcast('loading:hide');
				if (response.data.hasOwnProperty('session_token')) {
					// console.log(response.data.session_token);
					localStorageService.set('token', response.data.session_token);
				}
				return response;
			},
			// Request error interceptor captures requests that have been canceled by a previous request interceptor. It can be used in order to recover the request and sometimes undo things that have been set up before a request, like removing overlays and loading indicators, enabling buttons and fields and so on.
			// Sometimes our backend call fails. Other times it might be rejected by a request interceptor or by a previous response interceptor. In those cases, response error interceptor can help us to recover the backend call.
			'responseError': function(response) {
				if(response.status === 401 || response.status === 403 || response.status === 0) {
					$log.error(response.status);
					$injector.get('$state').transitionTo('login');
				}
				// console.log(response);
				// $rootScope.$broadcast('loading:hide');
				return $q.reject(response);
			}
		};
	}
})();