String Functions are not working in Multer - node.js

Question

While I tried to rename uploaded image with date, an error is being thrown and it shows "Cannot read property 'isLoggedIn' of undefined".
I would be happy if anyone could solve the problem. Thanks in advance
I think from Multer an error is thrown and it goes to error handling middleware.
here is my app.js
const path = require('path');
const express = require('express');
const bodyParser = require('body-parser');
const mongoose = require('mongoose');
const session = require('express-session');
const MongoDBStore = require('connect-mongodb-session')(session);
const csrf = require('csurf');
const flash = require('connect-flash');
const multer = require('multer');
const errorController = require('./controllers/error');
const User = require('./models/user');
const MONGODB_URI = 'mongodb+srv://axxxxn:xxxxxx#cluster0-sm6lw.mongodb.net/sxhxoxxxp';
const app = express();
const store = new MongoDBStore({
uri: MONGODB_URI,
collection: 'sessions'
});
const csrfProtection = csrf();
const fileStorage = multer.diskStorage({
destination: (req, file, cb) => {
cb(null, 'images');
},
filename: (req, file, cb) => {
cb(null, new Date().toISOString() + '-' + file.originalname );
}
});
app.set('view engine', 'ejs');
app.set('views', 'views');
const adminRoutes = require('./routes/admin');
const shopRoutes = require('./routes/shop');
const authRoutes = require('./routes/auth');
app.use(bodyParser.urlencoded({ extended: false }));
app.use(multer({ storage: fileStorage }).single('image'));
app.use(express.static(path.join(__dirname, 'public')));
app.use(
session({
secret: 'my secret',
resave: false,
saveUninitialized: false,
store: store
})
);
app.use(csrfProtection);
app.use(flash());
app.use((req, res, next) => {
res.locals.isAuthenticated = req.session.isLoggedIn;
res.locals.csrfToken = req.csrfToken();
next();
});
app.use((req, res, next) => {
//throw new Error('Sync Dummy');
if (!req.session.user) {
return next();
}
User.findById(req.session.user._id)
.then(user => {
//throw new Error('Dummy');
if(!user){
return next()
}
req.user = user;
next();
})
.catch(err => {
next(new Error(err));
});
});
app.use('/admin', adminRoutes);
app.use(shopRoutes);
app.use(authRoutes);
app.get('/500', errorController.get500);
app.use(errorController.get404);
app.use((error, req, res, next) => {
res.status(404).render('500', {
pageTitle: 'Error 500',
path: '/500',
isAuthenticated: req.session.isLoggedIn
});
});
mongoose
.connect(MONGODB_URI)
.then(result => {
app.listen(3000);
console.log('connected');
})
.catch(err => {
console.log(err);
});

Answer 1

I had this problem on windows: new Date().toISOString() gives a 'zulu' date, something like
2020-08-13T10:01:36.688Z. But : is not a valid character in windows filenames. This worked for me:
const dateStr = new Date().toISOString().replace(/:/g, '-');
cb(null, dateStr + '-' + file.originalname);  

Answer 2

I think this problem is related to Windows, maybe Windows will be angry if you try to put ":" inside fileName so instead of "toIsoString" you can use "toDateString" like this:
cb(null, new Date().toDateString().replace(/\s/g, '_') + '_' + new Date().toTimeString().replace(/[\s:]/g, '_') + file.originalname);
By the way, this is more readable for the user and contains all the information (date and time)
Finally, make sure to replace '\\' to '/' inside file.path when you add imageUrl to db like:
{
...,
imageUrl: req.file.path.replace('\\', '/'),
...
}