The system-wide location for the containers storage.conf is
/usr/share/containers. The existence of a file in /etc/containers
completely overrides this (see containers-storage.conf(5)).
If no file is found at /etc/containers/storage.conf then fall back to
reading the config from /usr/share/containers/storage.conf.
If neither file exists, this is an error since the default config should
be packaged with any tool that requires it (skopeo, podman, etc).
Containers with the `containers-storage` are bind mounted to
the osbuild store. This helper function bind mounts the
containers-storage from the store into the `/containers/storage`
so that stages that require containers can then make use of these
containers.
This will hoist even more code into util out of the skopeo stage.
Now a caller can call:
with containers.container_source(image) as (image_name, image_source):
print(f"{image_name}, {image_source}")
to process containers inputs.
This hoists container handling code from the skopeo stage into
util/containers. It is prep for adding another stage that accepts
containers as an input. The code is common so we should share it
amongst all stages that use containers as input.
