Node.js 手动登录User-Passport.js？

我的目标是拥有一个带有两个选项的发布路线——要么用户已经拥有一个帐户，要么没有。如果用户没有帐户，它将创建一个帐户-这是有效的。但是，如果用户确实有帐户，我需要更新他们的当前信息，然后登录

一切正常，但是如果用户已经拥有帐户，我无法登录。这可能吗？

 router.post("/career-test", function(req, res){

    User.findOne({username: req.body.username}, function(err, existingUser) {
    if (err) {
    return done(err);
    }

    if (!existingUser) {


    var newUser = new User({username: req.body.username});
    console.log('newUser' + newUser)
    User.register(newUser, req.body.password, function(err, user){

        user.career1.name =  req.body.career1Name;
        user.career2.name =  req.body.career2Name;
        user.career3.name =  req.body.career3Name;
        user.career4.name =  req.body.career4Name;
        user.career5.name =  req.body.career5Name;
        user.save()

    if(err){
    req.flash("error", err.message);
    res.redirect('back')
    return res.render("register");

    }
    passport.authenticate("local")(req, res, function(){
    res.redirect("/results"); 
    });
    });

    } else { 

    res.redirect("/results"); 
    });
    }
    });
    });

这是指用户已经存在/找到的情况

      existingUser.career1.name =  req.body.career1Name;
      existingUser.career2.name =  req.body.career2Name;
      existingUser.career3.name =  req.body.career3Name;
      existingUser.career4.name =  req.body.career4Name;
      existingUser.career5.name =  req.body.career5Name;
      existingUser.save()

现在我需要登录现有用户。。。这可能吗？

 router.post("/career-test", function(req, res){

    User.findOne({username: req.body.username}, function(err, existingUser) {
    if (err) {
    return done(err);
    }

    if (!existingUser) {


    var newUser = new User({username: req.body.username});
    console.log('newUser' + newUser)
    User.register(newUser, req.body.password, function(err, user){

        user.career1.name =  req.body.career1Name;
        user.career2.name =  req.body.career2Name;
        user.career3.name =  req.body.career3Name;
        user.career4.name =  req.body.career4Name;
        user.career5.name =  req.body.career5Name;
        user.save()

    if(err){
    req.flash("error", err.message);
    res.redirect('back')
    return res.render("register");

    }
    passport.authenticate("local")(req, res, function(){
    res.redirect("/results"); 
    });
    });

    } else { 

    res.redirect("/results"); 
    });
    }
    });
    });

---

事实证明这很容易。在这里找到了答案：

保存现有用户数据后，只需执行以下操作：

req.login(existingUser, function(err) {
  if (err) return next(err)
});