Lower memory consumption: SpringSingleMultipartFileWriter

The write method of SpringSingleMultipartFileWriter.java uses a lot of memory:

@Override
  protected void write (Output output, String key, Object value) throws EncodeException {
    val file = (MultipartFile) value;
    writeFileMetadata(output, key, file.getOriginalFilename(), file.getContentType());

    byte[] bytes;
    try {
      bytes = file.getBytes();
    } catch (IOException ex) {
      throw new EncodeException("Getting multipart file's content bytes error", ex);
    }
    output.write(bytes);
  }

Is it possible to use file.getInputStream() in some kind of way? It will require a lot of refactoring… now large files are loaded inside the memory twice.

[Toparvion]

Facing the same issue with transferring uploaded files through Feign-equipped applications. It would be much more efficient for memory consumption if Feign could treat uploaded files as byte streams rather than byte arrays.

[tmoreira2020]

Thanks @koziolk for the fast response. I was thinking to do the same approach and have two clients for the short term.