This avoids spurious failure with 'localhost'.
It should also be more correct the inventory contains uncached hosts
which are not in `k8s_cluster` and therefore should not be Kubespray
business.
(We still use hostvars for uncached hosts, because it's easier to select
on 'ansible_default_ipv4' that way and does not change the end result)
- Lookup was not returning a list, making the difference filter spit out
garbage -> query always return a list
- hostvars is a dictionnary, so convert to list before selectattr and
map back to only get keys
Since a2019c1c2 (Add a JSON schema describing the packages install
structure, 2024-04-25), we use a custom structure to select which
packages should be installed on a particular host OS.
This has proven too rigid in practice, and the query is pretty
complicated.
Replace this by simply using an array of jinja conditions for the
packages, which should be easier to understand for everyone and more
flexible.
Also remove the associated schema and validation which are no longer
needed.
Testing for group membership with group names makes Kubespray more
tolerant towards the structure of the inventory.
Where 'inventory_hostname in groups["some_group"] would fail if
"some_group" is not defined, '"some_group" in group_names' would not.
Uses the logic introduced in the previous patch to convert all
kubernetes/preinstall/vars/* os specific files to the `pkgs`
dictionary.
Some niceties for devs:
- always validate the `pkgs` variable to catch mistakes in CI.
- ensure that `pkgs` is always sorted. This makes it easier to find the
packages you're looking for.
According to the canal github[1] the repo is not maintained over 5 years.
In addition, the README says
```
Originally, we thought we might more deeply integrate the two projects
(possibly even going as far as a rebranding!). However, over time it
became clear that that wasn't really necessary to fulfil our goal of
making them work well together. Ultimately, we decided to focus on
adding features to both projects rather than doing work just to
combine them.
```
So it is difficult to support canal by Kubespray at this situation.
[1]: https://github.com/projectcalico/canal
