Inject instanced host snaps to the provider

[lengau]

What needs to get done

Add a way to support a snap instance key from the host when injecting it into the client, without instancing the snap inside the client or requiring that snapd in there even have parallel installs enabled.

Essentially, this needs an optional instance_key in

craft-providers/craft_providers/actions/snap_installer.py

Line 317 in 5547eed

def inject_from_host(*, executor: Executor, snap_name: str, classic: bool) -> None:

and then passthroughs in related places.

Why it needs to get done

Snapd has parallel installs as an experimental option. We need to be able to get an instanced version of a host snap and install it without being instanced.

See also: canonical/craft-application#411

[mr-cal]

Downstream issues:

• Cannot use parallel installations of snapcraft if a non-aliased version is not installed snapcraft#4683
• Parallel installation of snapcraft not passed to LXD instance snapcraft#4927

[syncronize-issues-to-jira]

Thank you for reporting us your feedback!

The internal ticket has been created: https://warthogs.atlassian.net/browse/CRAFT-3259.

This message was autogenerated

[lengau]

Downstrteam: canonical/craft-application#411