Re: [libvirt] [PATCH 0/3] libxl: Add a test suite for libxl_domain_config generator

On 07/26/2017 05:07 PM, Marek Marczykowski-Górecki wrote: > On Fri, Jul 14, 2017 at 05:59:57PM -0600, Jim Fehlig wrote: > > On 07/01/2017 08:16 PM, Marek Marczykowski-Górecki wrote: > > > On Sun, Feb 26, 2017 at 07:02:24PM -0700, Jim Fehlig wrote: > > > > Long ago danpb posted some patches to test libvirt domXML to > > > > libxl_domain_config conversion > > > > > > > > https://www.redhat.com/archives/libvir-list/2014-May/msg01102.html > > > > > > > > Some of the prerequisite patches were pushed, but we've never managed > > > > to push patches actually providing the conversion tests. I sent several > > > > follow-ups to Dan's work but never converged on a satisfactory solution > > > > for all the Xen versions supported by libvirt. The last attempt was in > > > > Sept 2014 > > > > > > > > https://www.redhat.com/archives/libvir-list/2014-September/msg00698.html > > > > > > > > I tried to revive the work in Jan 2015, but that also stalled > > > > > > > > https://www.redhat.com/archives/libvir-list/2015-January/msg00924.html > > > > > > > > Fast-forward over 2.5 years from the first attempt and libvirt no longer > > > > supports older Xen versions 4.2 and 4.3 that were proving to be problematic. > > > > Starting with Xen 4.5 libxl added support for libxl_domain_config_from_json, > > > > which provides a way to implement the conversion tests that work with all > > > > Xen versions >= 4.5 (including latest xen.git master). > > > > > > Few more months have passed... > > > > And a few more weeks :-). Sorry for the delay. Slowly catching up on libvirt > > mail after some time away... > > It's me this time... > > > > FWIW, I've tested it with Xen 4.6. The patch needs very minor update: > > > - s/VIRT_TEST_MAIN_PRELOAD/VIR_TEST_MAIN_PRELOAD/ > > > - add xencaps argument to libxlBuildDomainConfig cal > > > > > > > After that, it works! When I made some test to fail, reported error is > > > not so helpful ("libvirt: Xen Light Driver error : internal error: > > > Expected and actual libxl_domain_config objects do not compare"), but it > > > do catch failures. > > > Then, if I change strcmp to virTestCompareToString, the output is much > > > more helpful. > > > > Thanks for the improvements. I noticed you included them in your V2 of patch > > 3/3. I assume you needed patches 1 and 2 as well? > > Yes, in this tests shape. But see below. > > > > I'd really love to have it merged, mostly because I want to add more tests > > > using this framework (see "Add setting CPU features (CPUID) with > > > libxenlight driver" thread). > > > > I really dislike patches 1 and 2. They remove very useful checks IMO. > > Shortly after posting the series in Feb, I tried mocking the emulator > > checks. I failed quite a bit before coming up with something that worked, > > yet not so satisfying :-). I'll attach the (now rather old) patches for > > reference. > > My independent try to this test approach ("tests: check domain XML to > libxl structures conversion") had much simpler (but uglier) solution for > this problem: use /bin/true as emulator path (replaced in runtime, just > after loading XML from file). Ah, clever and devious. For that matter all the test files could be changed to <emulator>/bin/true</emulator> :-). > > Do you have time to update these old patches, test, and repost to the list? > > Or perhaps have better ideas on mocking, or approaches that avoid the need > > for 1/3 and 2/3. > > If using /bin/true as emulator path is acceptable, I can finish this and > post updated version. Did you have any comment on the approach taken in the attachments to this thread? Particularly the patch titled "libxl: make emulator checks mockable"?