[QA] Resetting database to original state after tests

[Juliusz Gonera]

On 03/05/2014 12:23 PM, Chris McMahon wrote:
>
> I have had a couple of (very preliminary) conversations with Rob 
> Lanphier along these lines.
>
> Today we support (for some value of "support") two test environments: 
>  beta labs and test2wiki.  What might be possible in the future is to 
> support a set of test environments beyond just beta and test2wiki. 
>  (One example would be a test environment on bare metal, for 
> performance-test reasons.)
>
> I think a beta-esque test env with a db that returns to a snapshot 
> state at particular times would be really useful.

Sorry for not replying to this earlier. What I meant by environments was 
more along the lines of modes that can be activated on demand in any MW 
instance, be it on beta labs or on developer's local machine, similar to 
what Rails, Django and other MVC frameworks have [1].

I'm not sure about the exact implementation, but just to illustrate my 
point, we could do something like this:

if ( $wgEnv === 'test' ) {
     // expose DB reset API
}

Then we could have a beta labs instance that would have $wgEnv = 'test' 
where all the tests could run and reset the database using this API. We 
could also ship mediawiki-vagrant with MW available on two different 
ports, e.g. apart from 8080, we could have 127.0.0.1:8081 that would use 
use $wgEnv = 'test' and point to a different MySQL database. In this 
situation invoking bundle exec cucumber would run all the tests on a 
separate database without messing up developer's dev database.

[1] http://guides.rubyonrails.org/testing.html#the-test-environment

-- 
Juliusz