Multer is uploading file, but not populating req.files - node.js

Question

I'm studying node.js for a school project and I can't figure out why my code won't work. Whenever I upload a form that contains text and a file, the req.body gets populated but the req.files doesn't
server.js
const multer = require('multer')
const bparser = require('body-parser')
app.use(bparser.urlencoded(settings.body_parser))
...
let multer_storage = multer.diskStorage({
destination: (req, file, cb) => {
cb(null, path.join(__dirname, settings.multer.destination))
},
filename: (req, file, cb) => {
cb(null, Date.now() + path.extname(file.originalname))
}
})
let multer_options = {
storage: multer_storage,
fileFilter: (req, file, cb) => {
if (settings.multer.allowed_files.indexOf(file.mimetype) >= 0)
cb(null, true)
cb(null, false)
}
}
app.use(multer(multer_options).any())
app.use("*", (req, res, next) => {
if (!req.session.user)
if (req.cookies.user)
req.session.user = req.cookies.user
next()
})
for (let i = 0; i < settings.routes.length; i++) {
app.use('/', require("./core/routers/" + settings.routes[i]))
}
...
./core/routers/post.js
const router = require('express').Router()
...
router.post('/post/share/', (req, res) => {
let data = {
title: req.body.title,
user: req.session.user,
post: req.files[0].path,
tags: req.tags.split(" ")
}
post.create(data).then((result) => {
return result
})
})
I keep encountering a "TypeError: Cannot read property 'path' of undefined"

Answer 1

When you call cb(null, false) in your fileFilter method, you tell multer that it shouldn't process the file, but it will still enter your middleware with: req.files being undefined that's why you get that error.
If you don't want it to enter to your middleware if the file wasn't processed, then you should pass an error to the callback instead:
let multer_options = {
storage: multer_storage,
fileFilter: (req, file, cb) => {
if (settings.multer.allowed_files.indexOf(file.mimetype) >= 0)
return cb(null, true); // this return is missing
cb(new Error('Invalid file'));
}
}
In any case, you're missing a return statement before cb(null, true); otherwise you're calling twice the callback, once with true and the other once with false
To sum up, if you don't pass an Error to the fileFilter function, you should check for the presence of req.files in your middleware.

Answer 2

Or you can try the code below:
var tmp_path = req.file.path;