Oct 26 14:09:31 uffizi python3[16259]: [2016-10-26 14:09:31,108: ERROR/MainProcess] Task swh.loader.git.tasks.ReaderGitRepository[a9df82ad-802f-4271-8c49-73d8ed4e4746] raised unexpected: UnboundLocalError("local variable 'err' referenced before assignment",)
Oct 26 14:09:31 uffizi python3[16259]: Traceback (most recent call last):
Oct 26 14:09:31 uffizi python3[16259]: File "/usr/lib/python3/dist-packages/celery/app/trace.py", line 240, in trace_task
Oct 26 14:09:31 uffizi python3[16259]: R = retval = fun(*args, **kwargs)
Oct 26 14:09:31 uffizi python3[16259]: File "/usr/lib/python3/dist-packages/celery/app/trace.py", line 437, in __protected_call__
Oct 26 14:09:31 uffizi python3[16259]: return self.run(*args, **kwargs)
Oct 26 14:09:31 uffizi python3[16259]: File "/usr/lib/python3/dist-packages/swh/loader/git/tasks.py", line 53, in run
Oct 26 14:09:31 uffizi python3[16259]: return loader.load(repo_url)
Oct 26 14:09:31 uffizi python3[16259]: File "/usr/lib/python3/dist-packages/swh/loader/git/reader.py", line 157, in load
Oct 26 14:09:31 uffizi python3[16259]: self.fetch_data()
Oct 26 14:09:31 uffizi python3[16259]: File "/usr/lib/python3/dist-packages/swh/loader/git/updater.py", line 303, in fetch_data
Oct 26 14:09:31 uffizi python3[16259]: do_progress)
Oct 26 14:09:31 uffizi python3[16259]: File "/usr/lib/python3/dist-packages/swh/loader/git/updater.py", line 232, in fetch_pack_from_origin
Oct 26 14:09:31 uffizi python3[16259]: progress=do_activity)
Oct 26 14:09:31 uffizi python3[16259]: File "/usr/lib/python3/dist-packages/dulwich/client.py", line 555, in fetch_pack
Oct 26 14:09:31 uffizi python3[16259]: proto, can_read = self._connect(b'upload-pack', path)
Oct 26 14:09:31 uffizi python3[16259]: File "/usr/lib/python3/dist-packages/dulwich/client.py", line 643, in _connect
Oct 26 14:09:31 uffizi python3[16259]: raise err
Oct 26 14:09:31 uffizi python3[16259]: UnboundLocalError: local variable 'err' referenced before assignment

The message is not so clear but the code references (dulwich/client.py around line 643):

```
        err = socket.error("no address found for %s" % self._host)
        for (family, socktype, proto, canonname, sockaddr) in sockaddrs:
            s = socket.socket(family, socktype, proto)
            s.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
            try:
                s.connect(sockaddr)
                break
            except socket.error as err:
                if s is not None:
                    s.close()
                s = None
        if s is None:
            raise err
```

So when trying to raise the 'err' variable, it's when s is None
and s is None when the socket opening somehow fails.

I don't grok why err is not defined since it is (maybe the try except which overrides it).
So it must be environment related (firewall or something).

Will try in another worker.

Issues: https://github.com/jelmer/dulwich/issues/459
PR: https://github.com/jelmer/dulwich/issues/460

Well, an issue in dulwich was making unclear the reason.
Fixing the code in dulwich, made the error clear.
github.com was not resolved in uffizi (it is now).