diff mercurial/hgweb/server.py @ 52157:891f6d56f3db stable

hgweb: skip logging ConnectionAbortedError

Not stacktracing on `ConnectionResetError` was added in 6bbb12cba5a8 (though it
was spelled differently for py2 support), but for some reason Windows
occasionally triggers a `ConnectionAbortedError` here across various *.t files
(notably `test-archive.t` and `test-lfs-serve-access.t`, but there are others).
The payload that fails to send seems to be the html that describes the error to
the client, so I suspect some code is seeing the error status code and closing
the connection before the server gets to write this html.  So don't log it, for
test stability- nothing we can do anyway.

FWIW, the CPython implementation of wsgihander specifically ignores these two
errors, plus `BrokenPipeError`, with a comment that "we expect the client to
close the connection abruptly from time to time"[1].  The `BrokenPipeError` is
swallowed a level up in `do_write()`, and avoids writing the response following
this stacktrace.  I'm puzzled why a response is being written after these
connection errors are detected- the CPython code referenced doesn't, and the
connection is now broken at this point.  Perhaps these errors should both be
handled with the `BrokenPipeError` after the freeze.

(The refactoring away from py2 compat may not be desireable in the freeze, but
this is much easier to read, and obviously correct given the referenced CPython
code.)

I suspect this is what 6bceecb28806 was attempting to fix, but it wasn't
specific about the sporadic errors it was seeing.

[1] https://github.com/python/cpython/blob/b2eaa75b176e07730215d76d8dce4d63fb493391/Lib/wsgiref/handlers.py#L139

--- a/mercurial/hgweb/server.py	Fri Oct 25 17:15:53 2024 -0400
+++ b/mercurial/hgweb/server.py	Thu Oct 31 17:24:18 2024 -0400
@@ -8,7 +8,6 @@
 
 from __future__ import annotations
 
-import errno
 import os
 import socket
 import sys
@@ -124,8 +123,7 @@
             # I/O below could raise another exception. So log the original
             # exception first to ensure it is recorded.
             if not (
-                isinstance(e, (OSError, socket.error))
-                and e.errno == errno.ECONNRESET
+                isinstance(e, (ConnectionResetError, ConnectionAbortedError))
             ):
                 tb = "".join(traceback.format_exception(*sys.exc_info()))
                 # We need a native-string newline to poke in the log