[2.4, devel] WSGI application error

[Andres Rodriguez]

: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36)
2018-02-08 00:01:45 -: [critical] WSGI application error
        Traceback (most recent call last):
          File "/usr/lib/python3/dist-packages/twisted/python/context.py", line 122, in callWithContext
            return self.currentContext().callWithContext(ctx, func, *args, **kw)
          File "/usr/lib/python3/dist-packages/twisted/python/context.py", line 87, in callWithContext
            self.contexts.pop()
          File "/usr/lib/python3/dist-packages/provisioningserver/utils/twisted.py", line 875, in callInContext
            return func(*args, **kwargs)
          File "/usr/lib/python3/dist-packages/twisted/web/wsgi.py", line 522, in run
            self.started = True
        --- <exception caught here> ---
          File "/usr/lib/python3/dist-packages/twisted/web/wsgi.py", line 500, in run
            self.write(elem)
          File "/usr/lib/python3/dist-packages/twisted/web/wsgi.py", line 455, in write
            self.reactor, wsgiWrite, self.started)
          File "/usr/lib/python3/dist-packages/twisted/internet/threads.py", line 122, in blockingCallFromThread
            result.raiseException()
          File "/usr/lib/python3/dist-packages/twisted/python/failure.py", line 385, in raiseException
            raise self.value.with_traceback(self.tb)
        builtins.AttributeError: 'NoneType' object has no attribute 'writeHeaders'

2018-02-08 00:01:45 asyncio: [error] Exception in callback <function AsyncioSelectorReactor.callLater.<locals>.run at 0x7ff0cfb1ad08>
handle: <Handle AsyncioSelectorReactor.callLater.<locals>.run>
Traceback (most recent call last):
  File "uvloop/cbhandles.pyx", line 47, in uvloop.loop.Handle._run
  File "/usr/lib/python3/dist-packages/twisted/internet/asyncioreactor.py", line 290, in run
    f(*args, **kwargs)
  File "/usr/lib/python3/dist-packages/twisted/web/wsgi.py", line 510, in wsgiError
    self.request.loseConnection()
  File "/usr/lib/python3/dist-packages/twisted/web/http.py", line 1474, in loseConnection
    self.channel.loseConnection()
AttributeError: 'NoneType' object has no attribute 'loseConnection'

[Blake Rouse (blake-rouse)]

Looks like the remote client dropped the tcp connection for http and twisted doesn't handle that correctly.