Generate destination path before file upload - multer - node.js

Question

Trying to make a folder before uploading a file to it. However, there is a problem if I do not update the server on the node when I try to download the file again, it is added to the already created folder. If I update the server, it creates a new folder and uploads it as needed. Please see the code, how can I improve it?
const db = require('../db');
const fs = require('fs');
const path = require('path');
const uuidv1 = require('uuid/v1');
const multer = require('multer');
console.log(uuidv1())
let storage = multer.diskStorage({
destination: `./uploads/${uuidv1()}`,
filename: (req, file, cb) => {
cb(null, 'test1' + '-' + Date.now() + '.' + path.extname(file.originalname));
}
});
let upload = multer({storage});
module.exports = (router) => {
router.get('/get', (req, res) => {
db.connect.query('SELECT * FROM habalka',
{type: db.sequelize.QueryTypes.SELECT}
).then(result => {
res.json(result);
})
});
router.post('/post', upload.any(), (req, res) => {
res.json('test');
});
return router;
};

Answer 1

Your issue is that when You start Your app it generates new uuid (once - at app startup) and passes as string to diskStorage method.
But You want to generate that path every-time when You upload a file.
So here is the solution:
Multer has feature to dynamically generate both destination path and filename.
So You've to pass a function that will generate path and return it in callback.
Example after reading this manual:
let storage = multer.diskStorage({
// pass function that will generate destination path
destination: (req, file, cb) => {
// initial upload path
let destination = path.join(__dirname, 'uploads'); // ./uploads/
// if user logged in and You store user object in session
if (req.session && req.session.user && req.session.user.id) {
destination = path.join(destination, 'users', req.session.user.id, uuidv1()); // ./uploads/users/8/generated-uuid-here/
}
else {
destination = path.join(destination, 'files', uuidv1()); // ./uploads/files/generated-uuid-here/
}
cb(
null,
destination
);
},
// pass function that may generate unique filename if needed
filename: (req, file, cb) => {
cb(
null,
Date.now() + '.' + path.extname(file.originalname)
);
}
});

Answer 2

My final code is here and it works !Thanks
const db = require('../db');
const fs = require('fs');
const uuid = require('uuid');
const path = require('path');
const multer = require('multer');
const shell = require('shelljs');
console.log(uuid())
let storage = multer.diskStorage({
// pass function that will generate destination path
destination: (req, file, cb) => {
// initial upload path
let destination = path.join(__dirname, '../uploads'); // ./uploads/
let id = uuid();
shell.mkdir('-p', './uploads/' + id);
destination = path.join(destination, '', id); // ./uploads/files/generated-uuid-here/
console.log('dest', destination)
cb(
null,
destination
);
},
// pass function that may generate unique filename if needed
filename: (req, file, cb) => {
let ext = file.originalname.substring(file.originalname.lastIndexOf('.'), file.originalname.length);
callback(null,file.originalname.split('.').slice(0,-1).join('.') + '-'+Date.now() +ext);
}
});
var upload = multer({storage: storage})
module.exports = (router) => {
router.get('/get', (req, res) => {
db.connect.query('SELECT * FROM habalka',
{type: db.sequelize.QueryTypes.SELECT}
).then(result => {
res.json(result);
})
});
app.post('/uploads', function (req, res) {
upload(req, res, function (err) {
if (err) {
console.log(err);
return res.end("Something went wrong!");
}else{
let ext = req.file.originalname.substring(req.file.originalname.lastIndexOf('.'), req.file.originalname.length);
var files='./uploads/'+req.file.originalname.split('.').slice(0 ,-1).join('.')+'-'+Date.now()+ext
console.log(req.file.originalname);
collection.insertOne({files},function(err,result){
if(err){
console.log("Something is Wrong");
}else{
res.json(result._id);
console.log(result);
}
})
}
});
})
return router;
};

Answer 3

In your multer middleware, you can do something like:
import util from "util";
import multer from "multer";
export const maxSize = 20 * 1024 * 1024;
export const __upoads_folder='/volume1/server/dash_rental_server/uploads';
let uploadFile = multer({
storage: multer.diskStorage({
destination: (req, file, cb) => {
const fileName = req.params.name;
let directoryPath = __upoads_folder + "/";
if (req?.params?.folder) { directoryPath += req.params.folder + '/' };
if (req?.params?.category) { directoryPath += req?.params?.category + '/' };
cb(null, directoryPath);
},
filename: (req, file, cb) => {
console.log(file.originalname);
cb(null, file.originalname);
},
}),
limits: { fileSize: maxSize },
}).single("file");
export let uploadFileMiddleware = util.promisify(uploadFile);
Then, in your route:
router.post("/upload/:folder/:category", async (req, res) => {
try {
await uploadFileMiddleware(req, res);
if (req.file == undefined) {
return res.status(400).send({ message: "Please upload a file!" });
}
res.status(200).send({
message: "Uploaded the file successfully: " + req.file.originalname,
});
} catch (err) {
if (err.code == "LIMIT_FILE_SIZE") {
return res.status(500).send({
message: `File size cannot be larger than ${maxSize / 1024 / 1024} MB!`,
});
}
res.status(500).send({
message: `Could not upload the file: ${req.file.originalname}. ${err}`,
});
}
});