When a client disconnects without completing a HTTP request, we were
attempting to process the partial request, which usually leads to a 400
error. These errors can pollute the logs and make it more difficult to
track down real bugs.
This change uses CloseNotifier to detect disconnects. In combination
with checking Content-Length, we can detect a disconnect before sending
the full payload, and avoid logging a 400 error.
This logic is only applied to PUT, POST, and PATCH endpoints, as these
are the places where disconnects during a request are most likely to
happen.
Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>
8fbc1de081