[Maas-devel] Problems when using MockLiveClusterToRegionFixture and TwistedRunTest

[Gavin Panella]

On 31 August 2014 18:12, Graham Binns <graham.binns at canonical.com> wrote:
> Hi Gavin (cc'ing maas-devel for reference).
>
> So, I've been trying to get
> pserv_services.tests.test_dhcp_probe_service to work with
> TwistedRunTest, but when I run `bin/test.pserv
> pserv_services.tests.test_dhcp_probe_service`, my tests fail (but not
> in a useful way), and I see the following in the log output:
>
> "ERROR: Unable to probe for rogue DHCP servers: Connection to the
> other side was lost in a non-clean fashion."
>
> Do what I may I can't stop the "Connection to the other side was lost
> in a non-clean fashion." from appearing… Any ideas?

That's a small red-herring. I think that's because you're not shutting
down the service in the test.

However, there's an obscured problem:

- t.p.amp.UnhandledCommand is the exception to catch, not
  t.spread.pb.NoSuchMethod.

- To get UnhandledCommand the protocol needs to completely lack support
  for the method. A stub that raises UnhandledCommand is not enough
  because AMP encodes that at a different level.

See http://paste.ubuntu.com/8200547/ for my fixes. To remove support for
a method I've mutated the protocol's _commandDispatch mapping. Better
would be to not pass the command in the call to makeEventLoop.

Hope that helps,

Gavin.