This is a simple example of Authentication and/or Authorization using html5's sessionStorage with AngularJS.

gistfile1.js

// Main module declaration
var myapp = angular.module('myapp', []);

// Set some actions to be performed when running the app
myezteam.run(['$location', '$rootScope', function($location, $rootScope) {

    // Register listener to watch route changes. 
    // We use this to make sure a user is logged in when they try to retrieve data
    $rootScope.$on( "$routeChangeStart", function(event, next, current) {
        
        // If there is no token, that means the user is not logged in.
        if(sessionStorage.getItem("token") == null) {
           
            // Redirect to login page
            window.location.href = "login.html";
        }         
    });
}]);

// A controller for the login page
myapp.controller('LoginController', ['$scope', '$http', function($scope, $http) {

	// If a user has check the "remember me" box previously and the email/password is in localStorage, set the email/password
	if(localStorage.getItem("email") != null && localStorage.getItem("password") != null) {
		$scope.user = {
			email: localStorage.getItem("email"),
			password: localStorage.getItem("password"),
			remember: localStorage.getItem("remember")
		}
	} 

	// Login method when the form is submitted
	$scope.login = function() {
	
		// Authenticate the user - send a restful post request to the server and if the user is authenticated successfully, a token is returned
		$http.post('http://example.com/login', $scope.user)
			.success(function(response) {
			  
			  // Set a sessionStorage item we're calling "token"
				sessionStorage.setItem("token", response.token);
				
				// Redirect to wherever you want to
				window.location = 'index.html';
			})
	}
}]);

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