How to use connect-flash with passport-local - node.js

Question

hello every one i was trying to use connect-flash with passport local but can not seem to find relevant info either on the docs and other sources,if any one can guide me on this and tell me what i went wrong ,thanks.And why does request to login-fail gives this error:-
ERROR is AxiosError: Request failed with status code 404
but when i test the route with rest client on vscode it responses perfectly like seen
here.
also when i check the database right after i click submit on the route
there will be two sessions stored consecutively one having the flash(the first) and the other not like this:-
session:
{"cookie":{"originalMaxAge":259200000,"expires":"2023-01-16T12:30:14.395Z","secure":false,"httpOnly":true,"path":"/"},"flash":{"error":["Incorrect password"]}}
session:
{"cookie":{"originalMaxAge":259200000,"expires":"2023-01-16T12:30:14.453Z","secure":false,"httpOnly":true,"path":"/"}}
why this is happening?
userRoutes.js
const router = require("express").Router();
const passport = require("passport");
const { ObjectID } = require("mongodb");
const LocalStrategy = require("passport-local");
const bcrypt = require("bcrypt");
const flash = require("connect-flash");
const User = require("../models/userModel.js");
router.route("/register").post(
(req, res, next) => {
User.findOne({ fullName: req.body.fullName }, (err, user) => {
if (err) {
next(err);
} else if (user) {
res.redirect("/");
} else {
const {
fullName,
email,
id,
department,
stream,
batch,
sex,
age,
phoneNumber,
password,
} = req.body;
const hash = bcrypt.hashSync(password, 12);
console.log(hash);
const newUser = new User({
fullName,
email,
id,
department,
stream,
batch,
sex,
age,
phoneNumber,
password: hash,
});
newUser.save((err, data) => {
if (err) res.redirect("/");
next(null, data);
});
}
});
},
passport.authenticate("local", { failureRedirect: "/" }),
(req, res, next) => {
res.json({ user: "i am josh" });
}
);
router
.route("/login")
.post(
passport.authenticate("local", {
failureRedirect: "/login-fail",
failureFlash: true,
}),
(req, res) => {
res.json({ user: "i am josh" });
}
);
router.route("/login-fail").get((req, res) => {
// console.log(req.flash('error'));
res.json({ user: "josh" });
});
router.route("/logout").get((req, res) => {
req.logout();
res.redirect("/");
});
passport.serializeUser((user, done) => {
done(null, user._id);
});
passport.deserializeUser((id, done) => {
User.findOne({ _id: new ObjectID(id) }, (err, doc) => {
done(null, doc);
});
});
const customFields = {
usernameField: "email",
};
passport.use(
new LocalStrategy(customFields, (email, password, done) => {
User.findOne({ email }, (err, user) => {
//console.log(`User ${user.username} attempted to log in.`);
if (err) return done(err);
if (!user) return done(null, false, { message: "email does not exist" });
if (!bcrypt.compareSync(password, user.password)) {
return done(null, false, { message: "Incorrect password" });
}
return done(null, user);
});
})
);
function ensureAuthenticated(req, res, next) {
if (req.isAuthenticated()) {
return next();
}
res.json({ msg: "You are not authorized to view this page" });
}
module.exports = router;
server.js
require("dotenv").config();
const express = require("express");
const app = express();
const flash = require("connect-flash");
const session = require("express-session");
const passport = require("passport");
const mongoose = require("mongoose");
const MongoStore = require("connect-mongo");
const cors = require("cors");
app.use(express.json());
// app.use(express.urlencoded({ extended: true }));
app.use(cors());
app.use(flash());
app.use(
session({
secret: process.env.SESSION_SECRET,
resave: false,
saveUninitialized: true,
store: MongoStore.create({
mongoUrl: process.env.DB,
collection: "sessions",
}),
cookie: { secure: false, maxAge: 1000 * 60 * 60 * 24 * 3 },
})
);
app.use(passport.initialize());
app.use(passport.session());
mongoose
.connect(process.env.DB)
.then(() => {
console.log("DB connection successful");
})
.catch((err) => {
console.log(`DB connection Error: ${err}`);
});
const usersRouter = require("./routes/userRoutes");
app.use("/user", usersRouter);
const PORT = process.env.PORT || 5000;
app.listen(PORT, () => {
console.log(`server is running on port ${PORT}`);
});
module.exports = app;
ya,have seen the same question here on stack over flow but none of the answers work