拦截器在web开发中随处可见,比如站点的管理后台,不说所有人都能进入,所以就需要做一个拦截器并友好的跳转到提示页.下面我们简单实现一种,判断用户是否登录成功,登录不成功的用户自动重定向到登录页面.首先我们实现一个过滤器
exports.checkAuth=function(req, res, next) {

var token = req.signedCookies.token;

if (token && req.session.user && req.session.user.token === token)

next();

else if (token) {

//if invalid token or no session, should rebuild

var authInfo = user.getAuthInfo(token);

if (authInfo && authInfo.isAuth) {

req.session.user = {

userID: authInfo.userID,

userName: authInfo.userName,

isAuth: authInfo.isAuth,

token: token

}

next();


} else

res.redirect('/user/login');

} else

res.redirect('/user/login');
}


exports.checkAuth=function(req, res, next) {

var token = req.signedCookies.token;

if (token && req.session.user && req.session.user.token === token)

next();

else if (token) {

//if invalid token or no session, should rebuild

var authInfo = user.getAuthInfo(token);

if (authInfo && authInfo.isAuth) {

req.session.user = {

userID: authInfo.userID,

userName: authInfo.userName,

isAuth: authInfo.isAuth,

token: token

}

next();


} else

res.redirect('/user/login');

} else

res.redirect('/user/login');
}


然后定义路由,并加入过滤器
module.exports = function (app) {

app.get('/user/blogList',pageAdmin.checkAuth, pageAdmin.pageList);

app.all('/user/post',pageAdmin.checkAuth, pageAdmin.pagePost);
}


module.exports = function (app) {

app.get('/user/blogList',pageAdmin.checkAuth, pageAdmin.pageList);

app.all('/user/post',pageAdmin.checkAuth, pageAdmin.pagePost);
}

上面的路由定义接收3个参数,第一个是 请求的url路径,第二个是过滤器,如果满足过滤器将下一步进入路由处理函数,如果不满足将不会走到后面的路由定义函数里.