[Object: null prototype] {} for req.body

First I used upload function inside Controller.js(code given below) as per the GitHub multer tutorial and its working but the problem is I have to write the same code again and again in each js file where I’m using multer to upload file. For code reusability I’m trying to implement in the following way

I have created a file where in class method I’m using multer upload function. Files are getting uploaded successfully but the problem is I’m not able to use the req object after I call this class method. Below i m pasting the code and output.

FileStorage.js

const multer = require('multer');
const path = require('path');

class FileStorage{
    storeFileUsingMulter(req,res,folderName,fileFieldName){
        try{
            const storage = multer.diskStorage({
                destination : function(req , file ,cb){
                    let dest = path.join(path.resolve("../"),"\\FileStorage\\",folderName);
                    cb(null,dest);
                },
                filename: function(req,file,cb){
                    cb(null,file.originalname);
                }
            });
    
            const upload = multer({storage: storage}).single(fileFieldName);
            let result;
            upload(req,res,(err)=>{
                if(err)
                    throw err;
                else{
                    console.log(req.body);
                    result = req;
                    console.log(result.body);                                //printing the req.body object
                } 
            });
            console.log(result);                                                //printing undefined
            return result; 
        }
        catch(err){
            console.log(err);
            throw err;
        }
    }
}
module.exports = FileStorage;

Controller.js

const FileStorage = require('../functions/FileStorage');
const fileStorage = new FileStorage();

class ProfileController{
    async setUserProfile(req,res){
        try{
            await fileStorage.storeFileUsingMulter(req,res,"Profiles","profile");
            console.log("setUsrProfile()");
            console.log(req.body);                                   //printing [Object: null prototype] {}
            res.send("success");
        }
        catch(err){
            let r = {
                status : status[2],
                msg : err.message
            }
            console.log(err);
            res.send(r);
        }
    }
}
module.exports = ProfileController;

Point to note : Even if function is called first the other code is getting executed first console.log(“setUsrProfile()”); console.log(req.body); res.send(“success”); gets exectued before await fileStorage.storeFileUsingMulter(req,res,"Profiles","profile");

Ouptut

setUsrProfile()
[Object: null prototype] {}
[Object: null prototype] {
  dob: '****',
  gender: '***',
  ****: '***',
  ****: '***'
}
[Object: null prototype] {
  dob: '****',
  gender: '***',
  ****: '***',
  ****: '***'
}
undefined

Please let me know if there is any solution. I’m trying to find solution from last 2 days but nothing is working

[serp-ya]

Hi again! I’m solved issue on my side. I was use express-form-data for parsing form-data and this middleware was cut file data from request object and puted in to new field req.files

Now I updated Express to ^4.17.1 version and I don’t need any plugiun anymore for parsing form-data

UPD: problem don’t solved, because any another route miss form-data values

UPD2: this is a really strange issue… If we are use any middleware on the application level AND use multer middleware instance on the route level, we loose a body field and file field on our request object inside router handler.

And we can’t to use any multer instance on application level (rule from multer docs) or any another form-data handling middleware for support another routes, who use form-data values from the body field…

So a reason question - how to use multer to support form-data values on the all routes in our applications?.

[metrocoding]

@richardscheid are you sure that you are running into this exact issue? Celebrate seems to use Joi which should work with prototypeless objects (see sideway/joi#693).

If you are, I would recommend opening an issue on Celebrate, I don’t see why it shouldn’t work on prototypeless objects…

Hi, I have data in my req.body and I wanna access it before upload then set storage base on req.body with storageMaker function, what workaround you suggest?

export default () => {
    return function (req: Request, res: Response, next: NextFunction) {
        const storage = storageMaker(req.body);
        let upload = multer({
            storage: storage,
            fileFilter: mimeFilter,
        }).single("profile_picture");

        upload(req, res, function (err: any) {
            if (err) {
                res.status(500).send(
                    new ApiResponseResult(
                        false,
                        null,
                        [
                            new ResponseMessage(
                                ResponseMessageType.ERROR,
                                "Error in uploading file"
                            ),
                        ],
                        err
                    )
                );
                return;
            }
            next();
        });
    };
};