this is the spring boot API endpoint which receives request from react js frontend

@PostMapping(value = "/upload", consumes = {MediaType.APPLICATION_JSON_VALUE, 
MediaType.MULTIPART_FORM_DATA_VALUE})
public ResponseEntity<MessageResponse> uploadFile(@RequestPart("fileDB") String fileDB, 
@RequestPart("file") MultipartFile file) {
  String message = "";
  try {
    storageService.store(file, fileDB);

    message = "Uploaded the file successfully: " + file.getOriginalFilename();
    return ResponseEntity.status(HttpStatus.OK).body(new MessageResponse(message));
  } catch (Exception e) {
    message = "Could not upload the file: " + file.getOriginalFilename() + "!";
    return ResponseEntity.status(HttpStatus.EXPECTATION_FAILED).body(new 
 MessageResponse(message));
  }
}