Open Stack

On 04/09/14 10:45, Jay Pipes wrote:
> On 08/29/2014 05:15 PM, Zane Bitter wrote:
>> On 29/08/14 14:27, Jay Pipes wrote:
>>> On 08/26/2014 10:14 AM, Zane Bitter wrote:
>>>> Steve Baker has started the process of moving Heat tests out of the
>>>> Tempest repository and into the Heat repository, and we're looking for
>>>> some guidance on how they should be packaged in a consistent way.
>>>> Apparently there are a few projects already packaging functional tests
>>>> in the package <projectname>.tests.functional (alongside
>>>> <projectname>.tests.unit for the unit tests).
>>>>
>>>> That strikes me as odd in our context, because while the unit tests run
>>>> against the code in the package in which they are embedded, the
>>>> functional tests run against some entirely different code - whatever
>>>> OpenStack cloud you give it the auth URL and credentials for. So these
>>>> tests run from the outside, just like their ancestors in Tempest do.
>>>>
>>>> There's all kinds of potential confusion here for users and packagers.
>>>> None of it is fatal and all of it can be worked around, but if we
>>>> refrain from doing the thing that makes zero conceptual sense then
>>>> there
>>>> will be no problem to work around :)
>>>>
>>>> I suspect from reading the previous thread about "In-tree functional
>>>> test vision" that we may actually be dealing with three categories of
>>>> test here rather than two:
>>>>
>>>> * Unit tests that run against the package they are embedded in
>>>> * Functional tests that run against the package they are embedded in
>>>> * Integration tests that run against a specified cloud
>>>>
>>>> i.e. the tests we are now trying to add to Heat might be qualitatively
>>>> different from the <projectname>.tests.functional suites that already
>>>> exist in a few projects. Perhaps someone from Neutron and/or Swift can
>>>> confirm?
>>>>
>>>> I'd like to propose that tests of the third type get their own
>>>> top-level
>>>> package with a name of the form <projectname>-integrationtests (second
>>>> choice: <projectname>-tempest on the principle that they're essentially
>>>> plugins for Tempest). How would people feel about standardising that
>>>> across OpenStack?
>>>
>>> By its nature, Heat is one of the only projects that would have
>>> integration tests of this nature. For Nova, there are some "functional"
>>> tests in nova/tests/integrated/ (yeah, badly named, I know) that are
>>> tests of the REST API endpoints and running service daemons (the things
>>> that are RPC endpoints), with a bunch of stuff faked out (like RPC
>>> comms, image services, authentication and the hypervisor layer itself).
>>> So, the "integrated" tests in Nova are really not testing integration
>>> with other projects, but rather integration of the subsystems and
>>> processes inside Nova.
>>>
>>> I'd support a policy that true integration tests -- tests that test the
>>> interaction between multiple real OpenStack service endpoints -- be left
>>> entirely to Tempest. Functional tests that test interaction between
>>> internal daemons and processes to a project should go into
>>> /$project/tests/functional/.
>>>
>>> For Heat, I believe tests that rely on faked-out other OpenStack
>>> services but stress the interaction between internal Heat
>>> daemons/processes should be in /heat/tests/functional/ and any tests the
>>> rely on working, real OpenStack service endpoints should be in Tempest.
>>
>> Well, the problem with that is that last time I checked there was
>> exactly one Heat scenario test in Tempest because tempest-core doesn't
>> have the bandwidth to merge all (any?) of the other ones folks submitted.
>>
>> So we're moving them to openstack/heat for the pure practical reason
>> that it's the only way to get test coverage at all, rather than concerns
>> about overloading the gate or theories about the best venue for
>> cross-project integration testing.
>
> Hmm, speaking of passive aggressivity...

That's probably a fair criticism, in light of what Matt said about the 
failures of communication on both sides. I think a formal liaison 
program will be an enormous help here. However, it won't change the fact 
that keeping the tests for every project in a single repo with a single 
core team just won't scale.

> Where can I see a discussion of the Heat integration tests with Tempest
> QA folks? If you give me some background on what efforts have been made
> already and what is remaining to be reviewed/merged/worked on, then I
> can try to get some resources dedicated to helping here.

I made a list at one point:

https://wiki.openstack.org/w/index.php?title=Governance/TechnicalCommittee/Heat_Gap_Coverage&oldid=58358#Improved_functional_testing_with_Tempest

I'm not sure how complete it is, because a lot of those patches came 
from folks who were not Heat core members, and in some cases not even 
closely engaged in Heat development.

That wiki page was reviewed by the TC, although I was unable to make it 
to the meeting:

http://eavesdrop.openstack.org/meetings/tc/2014/tc.2014-07-29-20.02.html

> I would greatly prefer just having a single source of integration
> testing in OpenStack, versus going back to the bad ol' days of everybody
> under the sun rewriting their own.

I'd actually prefer some sort of plug-in system, where individual 
projects could supply tests and Tempest could load and run the 
appropriate ones for any particular test job in the correct environment. 
The Rally folks tell me that they support something like this for 
performance benchmarking... I'd really love it if the Rally and QA teams 
could work together to build something that benefits from *both* all the 
hard work the QA team has putting into making Tempest environments 
robust and some of the cool ideas in Rally.

If we continue to put all the integration tests in Tempest, then that 
means that every project will continue to gate against every other 
project, and that scales as O(n^2) in the number of projects. A plugin 
system would mean that e.g. Zaqar and Glance, say, would never gate 
against each other.

TBH I'd also be comfortable with e.g. Nova not gating against Heat. 
Gating against all dependent projects inevitably means the smaller, less 
mature projects will be in a position to accidentally cause chaos in the 
largest, most mature projects like Nova. I actually think it's going to 
be extremely rare that a change in Nova would break Heat, and on balance 
I think it's probably safer to just deal with that when it happens than 
to put Heat in a position where any problem with our tests can 
potentially grind Nova development to a halt.

That said, I absolutely want all of the python-*client projects to gate 
against Heat (and Horizon). So we would definitely be missing out if we 
can't find _some_ way to expose these integration tests outside of Heat.

> Note that I'm not talking about functional testing here, just the
> integration testing...

Yeah, you make a good point, and I don't think the distinction was 
actually clear (at least to me) until we discussed it in this thread. I 
probably shouldn't have replied glibly at 5.15pm on a Friday just before 
heading out of town for a week.

cheers,
Zane.