Copying of OCI layout before building a sandbox image

[JesseFarebro]

Version of Apptainer

apptainer version 1.1.8

Question

This behavior might differ depending on the context, for me, I'm building a Docker image into a sandbox container. In this case, it seems like Apptainer will copy the OCI layers from $APPTAINER_CACHEDIR to $APPTAINER_TMPDIR/bundle-temp-* before extracting them. Can't you just point Umoci at the layout in $APPTAINER_CACHEDIR and unpack those layers without needing the copy?