Почему multer undefined?

var storage = multer.diskStorage({
    destination: function (req, file, cb) {
        cb(null, './pubic/uploads')
    },
    filename: function (req, file, cb) {
        cb(null, file.fieldname + '-' + Date.now())
    }
})

var upload = multer({
    storage: storage
});

router.post('/create', upload.single('cover'), (req, res) => {
    console.log(req.file)
})