nodejs multer image upload : retain file name and extension

Question

I have a node.js express code below to upload a image and store into a default folder.

I realised that the file gets renamed and the extension is lost. can some one help me fix this error?

1.How to retain extension and file name

2. if a zip file is upload, i want to unzip it and upload it

   const __basefolder = "C:/Users/user/Desktop";
   const express = require('express');
   const multer = require('multer');
   const upload = multer({dest: __basefolder + '/uploads/images'});
   const app = express();
   const PORT = 3000;
   
   app.use(express.static('public'));
   app.post('/upload', upload.single('file'), (req, res) => {
       if(req.file) {
           res.json(req.file);
       }
       else throw 'error';
   });
   app.listen(PORT, () => {
       console.log('Listening at ' + PORT );
   });
   

Answer 1

You can define a filename-option in your disk-storage setup, which lets you choose your filename arbitrarily. Since you want the original file-name, you can use file.originalname (note that using this an existing file with the same name will be overwritten though):

const storage = multer.diskStorage({
    destination: (req, file, cb) => {
        cb(null, __basefolder + '/uploads/images');
    },
    filename: (req, file, cb) => {
        cb(null, file.originalname);
    }
})

const upload = multer({storage});

Regarding the second question: this has been answered before, see this or that for example.