Test-AutoBuild release 1.2.0 / virt-manager release 0.2.0
It has been a busy start to the week, both on work & non-work related projects. In the former case we made a new snapshot of virt-manager available – version 0.2.0. The major milestone in this release is the wizard for easy creation of Xen guest virtual machines. RPMs are not yet built into rawhide, but in the meantime there are screenshots of the installation process.
Even more important to me than virt-manager though, is the (long delayed) availability of the new Test-AutoBuild stable release series. Test-AutoBuild is a build & test automation harness aimed at upstream developmers, enabling “continuous integration” over a codebase. ie 24×7 the build harness checks latest code out of SCM repository, builds it, tests it, publishes the results, and starts process again. If you work in the Java world you may be aware of a project called CruiseControl – well, Test-AutoBuild is like CruiseControl on steriods – rather than just building & testing a single code module, it can be setup to perform full regression testing across a suite of dependant software packages.
For example, consider how it might apply to the virt-manager application – this depends on libvirt & xeninst; xeninst in turn depends on libvirt; libvirt in turn depends on xen. Because it is bleeding edge development, virt-manager is tracking latest upstream development branches of libvirt, xeninst & xen. Test-AutoBuild would enable build & test of the entire stack – checking out & building xen, then libvirt, then xeninst & finally virt-manager. Doing this 24×7 mean we can get feedback on any changes/breakage in the dependancy stack in a matter of hours if not sooner. If one weren’t building & testing the against the full stack the breakage might not come to light until months later, by which time resolving it could become a much more time consuming issue. The sooner you know about a problem, the sooner it can be resolved, and the less time is wasted debugging in the long term.
Anyway back to my original point – the new release. Its hard to believe we first started work on this release branch about 2 years back with major re-factoring of the build workflow engine. Shortly after we started work to support caching an arbitrary number of historic biulds, extraction of SCM repository changelogs, and a whole host of other features. We could have released the code much sooner, with so much code change it seemed only prudent to invest an equally large amount of time ensuring the code is stable / reliable. So I spent as much time as possible over the following year basically just writing unit tests for the code & fixing the issues they uncovered.
The upshot is that this new release will provide a very good foundation for further development of Test-AutoBuild – with such an increased level of test coverage it ought to be possible to get new releases cut on a much more frequent basis – back to the classic open source mantra of release early, release often. With recent switch of DBus bindings from CVS to GIT, one of my highest priority development tasks is going to be the addition of GIT support (Test-AutoBuild currently supports Subversion, CVS, Mercurial, GNU Arch, Perforce & local filesystem).
Oh and if you’re thinking, I’m only one person I don’t need such automation of my code, think again. I develop on Fedora normally, but my autobuild server runs on Debian – I’ve lost count of number of occassions it has highlighted some incompatibility I mistakenly introduced – for example using a feature only supported in a very new version of a particular library or app, not commonly available.