Potential risk of easily overlooked resource leaks.

[asuraiv]

Hello. I have a question about feign.Response. When I look at the following code, there is code that does not return a Response object under certain conditions.

private static Response disconnectResponseBodyIfNeeded(Response response) throws IOException {
  final boolean shouldDisconnectResponseBody = response.body() != null
      && response.body().length() != null
      && response.body().length() <= MAX_RESPONSE_BUFFER_SIZE;
  if (!shouldDisconnectResponseBody) {
    return response;
  }

  try {
    final byte[] bodyData = Util.toByteArray(response.body().asInputStream());
    return response.toBuilder().body(bodyData).build();
  } finally {
    ensureClosed(response.body());
  }
}

For example, in a Spring Framework-based MVC application, when there is an error response, the 'Content-Length' header is missing, and in such cases, the resource is not released. Is there a reason for the existence of this code, and could it be code that is not necessary?

[kdavisk6]

This is intentional and only a resource leak if the response is not disconnected, delegating clean up to the caller, which in most cases is a proper Decoder, which does do the clean up later on.

The only use case where there may be a leak is if the return type of the proxied function is Response. In that case, the caller is accepting full responsibility for cleaning up the Response, since it is now no longer managed by Feign.