This is an AngularJS authentication service for using JSON Web Tokens

authService.js

app.service('authService', ['$window', function ($window) {

        this.parseJwt = function (token) {
            if (token) {
                var base64Url = token.split('.')[1];
                var base64 = base64Url.replace('-', '+').replace('_', '/');
                return JSON.parse($window.atob(base64));
            } else return {};
        };

        this.saveToken = function (token) {
            $window.localStorage.jwtToken = token;
        };

        this.getToken = function () {
            return $window.localStorage.jwtToken;
        };

        this.isAuthed = function () {
            var token = this.getToken();
            if (token) {
                var params = this.parseJwt(token);
                var notExpired = Math.round(new Date().getTime() / 1000) <= params.exp;
                if (!notExpired) {
                    this.logout();
                }
                return notExpired;
            } else {
                return false;
            }
        };

        this.logout = function () {
            delete $window.localStorage.jwtToken;
        };

        // expose user as an object
        this.getUser = function() {
            return this.parseJwt(this.getToken())
        };
    }]);