Comment 5 for bug 1355820

While this is similar to the microversion stuff, it's actually a different thing. We want to be able to specify a minimum version of the ironicclient code that is running. However, as nova won't include ironicclient in requirements.txt, we can't ensure via pip that the right thing is installed.

At driver initialization time, we should check the version of ironicclient that is imported, and make sure it's >= some version that we hardcode. We'll bump that as necessary when a newer client is needed for some feature. We can start with the version currently in global-requirements.txt.