如何在passport js中添加登录错误闪烁消息

const passport = require('passport');
const LocalStrategy = require('passport-local').Strategy;

// 配置 Passport.js
passport.use(new LocalStrategy({
  // 配置本地策略的选项
}, (username, password, done) => {
  // 实现身份验证逻辑
}));

app.use(passport.initialize());
app.use(passport.session());

app.post('/login', passport.authenticate('local', {
  successRedirect: '/dashboard',
  failureRedirect: '/login',
  failureFlash: true // 启用登录错误闪烁消息
}));

app.post('/login', passport.authenticate('local', {
  successRedirect: '/dashboard',
  failureRedirect: '/login',
  failureFlash: true // 启用登录错误闪烁消息
}), (req, res) => {
  // 设置登录错误闪烁消息
  req.flash('error', '用户名或密码错误');
});

<% if (messages.error) { %>
  <div class="alert alert-danger">
    <%= messages.error %>
  </div>
<% } %>