dummysmtpd: don't die on client connection errors
The connection refused error in test-patchbomb-tls.t[1] is sporadic, but one of
the more often seen errors on Windows. I added enough logging to a file and
dumped it out at the end to make the following observations:
- The listening socket is successfully created and bound to the port, and the
"listening at..." message is always logged.
- Generally, the following is the entire log output, with the "accepted ..."
message having been added after `sslutil.wrapserversocket`:
listening at localhost:$HGPORT
$LOCALIP ssl error
accepted connect
accepted connect
$LOCALIP from=quux to=foo, bar
$LOCALIP ssl error
- In the cases that fail, asyncore.loop() in the run() method is exiting, but
not with an exception.
- In the cases that fail, the following is logged right after "listening ...":
Traceback (most recent call last):
File "c:\\Python27\\lib\\asyncore.py", line 83, in read
obj.handle_read_event()
File "c:\\Python27\\lib\\asyncore.py", line 443, in handle_read_event
self.handle_accept()
File "../tests/dummysmtpd.py", line 80, in handle_accept
conn = sslutil.wrapserversocket(conn, ui, certfile=self._certfile)
File "..\\mercurial\\sslutil.py", line 570, in wrapserversocket
return sslcontext.wrap_socket(sock, server_side=True)
File "c:\\Python27\\lib\\ssl.py", line 363, in wrap_socket
_context=self)
File "c:\\Python27\\lib\\ssl.py", line 611, in __init__
self.do_handshake()
File "c:\\Python27\\lib\\ssl.py", line 840, in do_handshake
self._sslobj.do_handshake()
error: [Errno 10054] $ECONNRESET$
- If the base class handler is overridden completely, the the first "ssl
error" line is replaced by the stacktrace, but the other lines are
unchanged. The client behaves no differently, whether or not the server
stacktraced.
In general, `./run-tests.py --local -j9 -t9000 test-patchbomb-tls.t
--runs-per-test 20` would show the issue after a run or two. With this change,
`./run-tests.py --local -j9 -t9000 test-patchbomb-tls.t --loop` ran 800 times
without a hiccup. This makes me wonder if the other connection refused messages
that bubble up on occasion are caused by a similar issue. It seems a bit
drastic to kill the whole server on account of a single communication failure
with a client.
# no-check-commit because of handle_error()
[1] https://buildbot.mercurial-scm.org/builders/Win7%20x86_64%20hg%20tests/builds/421/steps/run-tests.py%20%28python%202.7.13%29/logs/stdio
#!/usr/bin/env python
"""dummy SMTP server for use in tests"""
from __future__ import absolute_import
import asyncore
import optparse
import smtpd
import ssl
import sys
import traceback
from mercurial import (
server,
sslutil,
ui as uimod,
)
def log(msg):
sys.stdout.write(msg)
sys.stdout.flush()
class dummysmtpserver(smtpd.SMTPServer):
def __init__(self, localaddr):
smtpd.SMTPServer.__init__(self, localaddr, remoteaddr=None)
def process_message(self, peer, mailfrom, rcpttos, data):
log('%s from=%s to=%s\n' % (peer[0], mailfrom, ', '.join(rcpttos)))
def handle_error(self):
# On Windows, a bad SSL connection sometimes generates a WSAECONNRESET.
# The default handler will shutdown this server, and then both the
# current connection and subsequent ones fail on the client side with
# "No connection could be made because the target machine actively
# refused it". If we eat the error, then the client properly aborts in
# the expected way, and the server is available for subsequent requests.
traceback.print_exc()
class dummysmtpsecureserver(dummysmtpserver):
def __init__(self, localaddr, certfile):
dummysmtpserver.__init__(self, localaddr)
self._certfile = certfile
def handle_accept(self):
pair = self.accept()
if not pair:
return
conn, addr = pair
ui = uimod.ui.load()
try:
# wrap_socket() would block, but we don't care
conn = sslutil.wrapserversocket(conn, ui, certfile=self._certfile)
except ssl.SSLError:
log('%s ssl error\n' % addr[0])
conn.close()
return
smtpd.SMTPChannel(self, conn, addr)
def run():
try:
asyncore.loop()
except KeyboardInterrupt:
pass
def main():
op = optparse.OptionParser()
op.add_option('-d', '--daemon', action='store_true')
op.add_option('--daemon-postexec', action='append')
op.add_option('-p', '--port', type=int, default=8025)
op.add_option('-a', '--address', default='localhost')
op.add_option('--pid-file', metavar='FILE')
op.add_option('--tls', choices=['none', 'smtps'], default='none')
op.add_option('--certificate', metavar='FILE')
opts, args = op.parse_args()
if opts.tls == 'smtps' and not opts.certificate:
op.error('--certificate must be specified')
addr = (opts.address, opts.port)
def init():
if opts.tls == 'none':
dummysmtpserver(addr)
else:
dummysmtpsecureserver(addr, opts.certificate)
log('listening at %s:%d\n' % addr)
server.runservice(vars(opts), initfn=init, runfn=run,
runargs=[sys.executable, __file__] + sys.argv[1:])
if __name__ == '__main__':
main()