Javascript 为什么抛出user.validPassword不是函数错误？

我正在构建node.js应用程序，我使用的是Passport js，我从它的官方网站上阅读了Passport local doumentation，我使用了它的local Passport策略，它抛出了user.validPassword不是一个函数错误

app.js

require('./config/test')(passport);
app.use(passport.initialize());
app.use(passport.session());

router.get('/test', (req, res, next)=>{
  res.render('test');
});
router.post('/test',
  passport.authenticate('local', { successRedirect: '/',
                                   failureRedirect: '/test',
                                   failureFlash: true })
);

var passport = require('passport')
    , LocalStrategy = require('passport-local').Strategy;
const User = require('../model/students');

module.exports = function () {
    passport.use(new LocalStrategy(
        function (username, password, done) {
            User.findOne({ username: username }, function (err, user) {
                if (err) { return done(err); }
                if (!user) {
                    return done(null, false, { message: 'Incorrect username.' });
                }
                if (!user.validPassword(password)) {
                    return done(null, false, { message: 'Incorrect password.' });
                }
                return done(null, user);
            });
        }
    ));
}

index.js

require('./config/test')(passport);
app.use(passport.initialize());
app.use(passport.session());

router.get('/test', (req, res, next)=>{
  res.render('test');
});
router.post('/test',
  passport.authenticate('local', { successRedirect: '/',
                                   failureRedirect: '/test',
                                   failureFlash: true })
);

var passport = require('passport')
    , LocalStrategy = require('passport-local').Strategy;
const User = require('../model/students');

module.exports = function () {
    passport.use(new LocalStrategy(
        function (username, password, done) {
            User.findOne({ username: username }, function (err, user) {
                if (err) { return done(err); }
                if (!user) {
                    return done(null, false, { message: 'Incorrect username.' });
                }
                if (!user.validPassword(password)) {
                    return done(null, false, { message: 'Incorrect password.' });
                }
                return done(null, user);
            });
        }
    ));
}

config/test.js

require('./config/test')(passport);
app.use(passport.initialize());
app.use(passport.session());

router.get('/test', (req, res, next)=>{
  res.render('test');
});
router.post('/test',
  passport.authenticate('local', { successRedirect: '/',
                                   failureRedirect: '/test',
                                   failureFlash: true })
);

var passport = require('passport')
    , LocalStrategy = require('passport-local').Strategy;
const User = require('../model/students');

module.exports = function () {
    passport.use(new LocalStrategy(
        function (username, password, done) {
            User.findOne({ username: username }, function (err, user) {
                if (err) { return done(err); }
                if (!user) {
                    return done(null, false, { message: 'Incorrect username.' });
                }
                if (!user.validPassword(password)) {
                    return done(null, false, { message: 'Incorrect password.' });
                }
                return done(null, user);
            });
        }
    ));
}

节点版本：10.16.1

快速版本：4.16.1

---

发生此类错误的原因是.validPassword（密码）不是“用户”下的函数。简单的例子：

//I use this code on google.com main page.
var logo = document.querySelector("#hplogo");
logo.validPassword(""); // -> Error: .validPassword is not a function
// here I declare function under 'validPassword'
logo.validPassword = function(pass){
console.log("Validate password", pass);
};
logo.validPassword(""); // -> message: 'Validate password',''

---

所以我猜您丢失了函数本身。

它会抛出该错误，因为user.validPassword不是一个函数-它在哪里定义的？我从它的官方网站复制了它，它不正确吗！！也许你错过了一个步骤-唯一未知的是

用户

-也许你创建了一个错误的步骤。。。我认为有一些字段叫做

username

和

password

这是否回答了您的问题？