If the proxy timed out while reading a replicated policy multi-part
response body, it would transform the ChunkReadTimeout to a
StopIteration. This masks the fact that the backend read has
terminated unexpectedly. The document_iters_to_multipart_byteranges
would complete iterating over parts and send a multipart terminator
line, even though no parts may have been sent.
This patch removes the conversion of ChunkReadTmeout to StopIteration.
The ChunkReadTimeout that is now raised prevents the
document_iters_to_multipart_byteranges 'for' loop completing and
therefore stops the multi-part terminator line being sent. It is
raised from the GetOrHeadHandler similar to other scenarios that raise
ChunkReadTimeouts while the resp body is being read.
A ChunkReadTimeout exception handler is removed in the
_iter_parts_from_response method. This handler was previously never
reached (because StopIteration rather than ChunkReadTimeout was raised
from _get_next_response_part), but if it were reached (i.e. with this
change) then it would repeat logging of the error and repeat
incrementing the node's error counter.
This change in the GetOrHeadHandler mimics a similar change in the
ECFragGetter [1].
[1] Related-Chage: I0654815543be3df059eb2875d9b3669dbd97f5b4
Co-Authored-By: Tim Burke <tim.burke@gmail.com>
Change-Id: I6dd53e239f5e7eefcf1c74229a19b1df1c989b4a