Add Farms to config

[umohnani8]

Add 2 new fields to EngineConfig Farms and DefaultFarm for the podman buildfarm feature work.
Also update the ssh connection code to be able to add a new connection to a new or existing farm when the --farm is set in podman system connection add.

PR containers/podman#19358 will vendor this in.

[umohnani8]

@vrothberg @rhatdan PTAL

[vrothberg]

Carrying over my comment from the Podman PR:

---

I mean that it should not be part of the [engine] table but a new [buildfarm] table.

Ideally, it should not be part of containers.conf at all but a proper database or a dedicated predictable path for root and rootless. machine and conenction are (ab)using containers.conf already as a database but there is growing desire to change that, see #1566. containers.conf is a config file for users and we somehow abuse it as a database.

[rhatdan]

I agree this should at least be in a separate containers.conf file that can be updated on the fly. Moving everything to a dedicated connections.conf would be preferred to share both.

[vrothberg]

I agree this should at least be in a separate containers.conf file that can be updated on the fly. Moving everything to a dedicated connections.conf would be preferred to share both.

I suggest to integrate buildfarm into the brainstorming in #1566. I think it's a bad idea to use a config file as a DB.

BUT adding buildfarm as done in this PR will not change the status quo since we're already using containers.conf as a DB. It would be nice to find a more elegant solution in the future but we shouldn't block buildfarm's progress on this issue.

[umohnani8]

I updated the PR to create a separate Farms TOML table so we are not cluttering EngineConfig.
I am not a big fan of the Farms.Farms name but I really couldn't think of a better way to name it, any suggestions would be appreciated.

[vrothberg]

Requires tests and we need to set defaults (i.e., create an empty map to avoid the nil checks).

[umohnani8]

Tests are green!
@vrothberg @rhatdan PTAL

[rhatdan]

LGTM

[vrothberg]

The Podman PR containers/podman#19358 doesn't pass CI yet. Let's wait to be sure this PR has everything containers/podman#19358 needs.

[vrothberg]

LGTM
@rhatdan @Luap99 PTAL

[Luap99]

This is missing documentation in the man page

[umohnani8]

Added docs

[rhatdan]

/approve
/lgtm

[openshift-ci]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: rhatdan, umohnani8, vrothberg

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Details

Needs approval from an approver in each of these files:

• OWNERS [rhatdan,vrothberg]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment