我使用节点和Angular 通过JWT生成了令牌，并且无法检查用户是否被授权。
节点：

module.exports.authenticate = function(req, res) {
    var user = new User(req.body);
    User.findOne({
        username: req.body.username
    }, function(err, user) {
        if (err) throw err;

        if (!user) {
            res.json({ success: false, message: 'Authentication failed. User not found.' });
        }
        else if (user) {
            if (user.password != req.body.password) {
                res.json({ success: false, message: 'Authentication failed. Wrong password.' });
            }
            else {
                var token = jwt.sign(user, config.secret, {
                    expiresIn: 60*60*24
                });

                res.json({
                    success: true,
                    token: token
                });
            }
        }
    });
};

Angular ：

$http(req)
            .then(function (response) {
                console.log(response.data.success);
                if(response.data.success) {
                    var user = localStorage.setItem('token', JSON.stringify(response.data));
                    token = localStorage.getItem('token');
                    // console.log('User info: ', JSON.parse(getuser));
                    // window.location = "/dashboard";
                    return response.data;
                }
            }, function (response) {

            }
        );
    }

当我改变路线时如何检查令牌？
一般来说，我如何使用Token？