Support LXD projects in power control

[Stéphane Graber]

The LXD team unsurprisingly has quite a few systems running LXD which are used for VM hosting.

As those host a variety of VMs for a variety of purposes, we normally use projects to separate the different uses.

In this case, we'd like to have a project for our Ceph cluster VM/containers, a project for our Jenkins managed systems and a project for our MAAS managed VMs.

Sadly the MAAS power control does not let you specify a LXD project and so MAAS can only see and interact with instances in the default project.

This should be a pretty simple addition but one that would be quite welcome by anyone running a large LXD deployment.

[Stéphane Graber (stgraber)]

This would require pylxd to have a basic understanding of projects, then the power control work should be very trivial after that.

Worth remembering that the LXD team recommended MAAS uses/supports projects for the KVM feature too in order to avoid potential conflicts so doing the pylxd work would be useful for that too.

[Frode Nordahl (fnordahl)]

+1 due to the subtle differences in Juju provider drivers we are looking at the possibility of using MAAS as a front for LXD VMs as part of automated charm testing, and being able to use separate projects to enforce network separation would be very useful.