Angular Caching

contactsService_cached.js

angular.module('commonContactsModule').factory('contactsService', [
    '$q',
    '$http',
    function($q, $http) {
        function getCommon(targetEmail) {
            var url = 'https://www.conspire.com/commonContacts?email=' + encodeURIComponent(targetEmail);
            var promise;
            
            // want the cache to be global so it can be shared amongst all widgets
            if (typeof commonContactsCache === 'undefined') {
                commonContactsCache = {};
            }
            
            function success(response) {
                return response.data;
            }
            
            function failure(response) {
                return $q.reject(response.status);
            }
            
            // if this url is not cached, create a request and add it
            if (!commonContactsCache[url]) {
                commonContactsCache[url] = $http.get(url).then(success, failure);;
            }
            
            // return the cached result
            return commonContactsCache[url];
        }
        
        return {
            getCommon: getCommon
        };
    }
]);