File data gets saved with wrong file name for multi-file uploads

Hello. If I upload two files, one .json and the other a text file, and the text file is empty, the file data gets swapped, and the json data gets stored to the text file's name. I have also verified that if I upload multiple json files that contain valid json, the files get saved correctly to the right files. And then, in running another test, where I upload two valid json files and one empty text file, the error condition occurs again (one of the json files winds up with 0 bytes, and one of the json files gets saved to the text file's name).

This is a huge problem, so I hope you can help.

Here is how I am configuring multer, and I am testing the upload using postman:

function getStorage(config) {

    return multer.diskStorage({

        destination: function(req, file, cb) {

            // Controls where the file is stored

            cb(null, config.dest);

        },

        filename: function(req, file, cb) {

            // Controls what the file name will be. Existing file names will be overwritten.

            cb(null, file.originalname);

        }

    });

}


function createUploadModule(config) {

    return multer({ dest: config.dest, storage: getStorage(config)});

}

function configureUploadModule(config) {

    module.exports.uploadConfig = config;

    module.exports.uploadModule = createUploadModule(config).array(config.fileNameFormKey);

}

Please note that I have also tried removing the file rename function from getStorage(), but the same behavior still occurs, even when multer generates the file names.

Thanks for any insight on this.