upcoming nevow breakage

[warner]

The current version of Nevow (0.12.0) uses a feature of Twisted (request.received_headers) that was deprecated in Twisted-13.2.0 and will be removed entirely in the upcoming Twisted-16.0.0 .

When it is removed, unit tests (and almost certainly all other functionality) will fail with error messages that look like this:

  File "/Users/warner/stuff/tahoe/tahoe/ve/lib/python2.7/site-packages/twisted/web/http.py", line 1736, in allContentReceived
    req.requestReceived(command, path, version)
  File "/Users/warner/stuff/tahoe/tahoe/src/allmydata/webish.py", line 81, in requestReceived
    self.process()
  File "/Users/warner/stuff/tahoe/tahoe/ve/lib/python2.7/site-packages/nevow/appserver.py", line 146, in process
    self.fields = cgi.FieldStorage(self.content, self.received_headers,
exceptions.AttributeError: MyRequest instance has no attribute 'received_headers'

The Nevow maintainers are aware of this ​nevow#53, and with luck they'll make a new release before Twisted-16.0.0 comes out. If so, we just need to add the new Nevow to our deps tarball and we're good. We might want to increase our dependency on Nevow as well, to force an upgrade.

This ticket is mostly here in case Twisted releases before Nevow, so we'll have an idea of what the problem is.

[mithrandi]

Nevow 0.13.0 is now out. I'd appreciate it if someone could check whether we broke anything for Tahoe-LAFS, but hopefully everything should be fine.

[warner]

I just ran tests with the latest version. Works great. And the only remaining deprecation warning is one of our own (#2734, where we use conch in the 'manhole' module).

I've replaced nevow-0.11.1 with 0.13.0 in the tahoe-deps tarball, so the next "SUMO" tarball will include it.

Thanks for the quick release!

[warner]

Milestone renamed