gistfile1.txt

File file = new File(selectedImage.getPath());
        RequestBody body = RequestBody.create(MediaType.parse("image/*"), file);
        restApi.imageEndpoint.upload(user.getToken(), body)
                .observeOn(AndroidSchedulers.mainThread())
                .subscribeOn(Schedulers.io())
                .subscribe(this::successGetImageDTO, this::errorGetImageDto);
    
    
@Multipart
@POST("user/avatarUpload")
Observable<StatusResponse<UserDTO>> uploadAvatar(@Part("file\"; filename=\"cover.png\" ") RequestBody file);