使用 fs 在 multer 中重命名上传的图像

Question

When a user uploads a picture - I'm using multer by the way - with a name that contains a space, I want to replace the white-spaces with "-" before saving the file name to my Mysql table and then also rename the file that has been uploaded to the new name with the "-" . This is my code. It does rename and the Mysql table saves the new name with the hyphen but the image doesn't get uploaded for some reason, there's no error even, infact the POST request is actually successful.

router.post('/uploadpost', upload.single('image'), function(req, res){
var name = req.file.originalname;
var reName;
if(/\s/g.test(name)){
    reName = name.replace(" ", "-");
    fs.rename(req.file.path, reName, function(err){
        if(err){
            throw err;
        }

    });
}

Answer 1

Why not change the name when you save the file by Multer? Something like that:

function generateName(){
   return 'newname';
}

var storage = multer.diskStorage({
  destination: function (req, file, cb) {
    cb(null, '/tmp/my-uploads')
  },
  filename: function (req, file, cb) {
    cb(null, generateName()); // generate new name 
  }
})

var upload = multer({ storage: storage })

Documentation - https://github.com/expressjs/multer#diskstorage

Answer 2

You can Change file names easily in multer like hown below

const multer = require('multer');
let fs = require('fs-extra');

let storage = multer.diskStorage({
    destination: function (req, file, cb) {
        let path = `tmp/upload`;
        fs.mkdirsSync(path);
        cb(null, path);
    },
    filename: function (req, file, cb) {
        console.log(file);
        cb(null, file.fieldname + '-' + Date.now() + "." + extension);
    }
})

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

in above code I am giving file name like this file.fieldname fieldname is name of field using which you are sending images like fieldname could be "image" or anything and than - , Date.now() the date when you are uploading image and in last type or extension of file ex images-1602486722326.jpeg

OR

you can keep original name of image if you want like below

 filename: function (req, file, callback) {
        callback(null, file.originalname);
    }

this will get originalame of file and give it to the file which you are uploading UPDATE AND in MemoryStorage

const upload = multer({
    storage: multerS3({
        s3: s3,
        bucket: 'bucket_name',
        acl: 'public-read',
        key: function (request, file, cb) {
            console.log(file);    |--------------  change name here which you want to use
                                  |              
            cb(null, file.originalname);  use
        }
    })
}).array('upload', 1);