身份驗證ExpressJS-> passportJs：錯誤：發送標頭后無法設置標頭

Question

我正在使用passwordsjs在expressjs中進行身份驗證。 這是我的login.js代碼

passport.use(new LocalStrategy(
      function(username, password, done) {
        //console.log(username);
        Usercollection.findOne({ username: username }, function (err, user) {
          if (err) { return done(err); }
          if (!user) {
            return done(null, false, { message: 'Incorrect username.' });
          }
          else{
            return done(null, user);
          }
          // if (!user.validPassword(password)) {
          //   return done(null, false, { message: 'Incorrect password.' });
          // }

        });
      }
    ));
    passport.serializeUser(function(user, done) {
      done(null, user);
    });

    passport.deserializeUser(function(user, done) {
      done(null, user);
    });
    router.post('/', passport.authenticate('local', {
      successRedirect: '/automation-panel',
      failureRedirect: '/'
      })
    );

和users.js是

var express = require('express');
var router = express.Router();

/* GET users listing. */
router.get('/', function(req, res, next) {
    if (req.isAuthenticated()){  next(); }else {res.redirect('/');}
    // var sess = req.session;
    // if(sess.username != null){
    //  // res.send("hello "+ sess.username);
        // console.log(req.user.username);
    // }
    // else{
    //  req.redirect('/');
    // }
    // res.sendFile("fileUpload.html");
    // res.send("hello success");
    res.render('users/index', { title: 'Express'});
});

module.exports = router;

錯誤是

Error: Can't set headers after they are sent.
    at ServerResponse.OutgoingMessage.setHeader (http.js:690:11

Answer 1

router.get('/', function(req, res, next) {
    if (req.isAuthenticated()) {
        return res.render('users/index', { title: 'Express'});
    }
    else return res.redirect('/');
});

如果問題仍然存在，您將以某種方式進行另一個重定向。 所以也許這是問題所在。

router.post('/', passport.authenticate('local', {
    successRedirect: '/automation-panel',
    failureRedirect: '/'
    })
);

Answer 2

router.get('/', function(req, res, next) {
    if (req.isAuthenticated()){
        res.render('users/index', { title: 'Express'});
    }else {
        // Remove Below line. otherwise it will create infinite redirect loop.
        res.redirect('/');
    }
});