Open Stack

Excerpts from Monty Taylor's message of 2017-01-13 10:18:41 -0600:
> Hey all,
> 
> Part of the rollout plan for zuul v3 involves rolling out the new
> zookpeer-based nodepool launchers before we roll out zuul v3 itself.
> We've mostly spoken about this in a hand-wavy mannr so far, but I think
> we may have a fairly simple answer of how to approach it - so I'd like
> to propose the following:
> 
> * Make a branch of current nodepool master that we don't intend to merge
> back ever.
> 
> * Replace the OpenStack interactions in the provider_manager with zk api
> calls.
> 
> * Make a copy of our nodepool.yaml file that has min-ready set to zero
> for everything.
> 
> * Run a copy of nodepool from the branch pointed at the new v3
> zookeeper-based nodepool.
> 
> This should allow the shim nodepool to make real-time requests for nodes
> of the new nodepool and attach them to the 2.5 ansiblelaunchers. It
> makes the v3 nodepool the system of record. Once that's all in place, we
> should be able to also roll out a zuul v3 installation that is also
> pointed at the new nodepool, and have both shim-nodepool and zuul v3 be
> clients of nodepool v3.
> 
> Once we've finished migrating to zuul v3, we'll just delete the shim server.
> 
> Sound good to everyone?

Are the jobs so complicated that you can't just write a dedicated gearman
worker to do the translation to/from zk? I mean, gearman is really really
really simple for a reason.

Just saying.. might be simpler to write a throw-away 500 line python gear
worker, than modifying nodepool. And you know how against rewrites I am,
but in this case.. it's not a rewrite, but a shim.