Add wrapper for running apptainer on Mac

[afbjorklund]

Now that Apptainer has been moved from experimental, and accepted as LF project, it might be time for a wrapper ?

There is no client for apptainer, similar to nerdctl.

So use a small shell wrapper, to run "lima apptainer".

This is so that the user can follow the documentation, without having to write an extra lima prefix before every command:

https://apptainer.org/docs/user/main/quick_start.html

We might still have to document the read-only home.

FATAL:   While performing build: while creating SIF: while creating container: open /home/anders/lima/alpine.sif: read-only file system

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This is different from the situation for docker and podman.

Since they already have client binaries, available for Mac.

[afbjorklund]

It would be nice if this shell wrapper could automatically add the -B $HOME:$HOME mount, to run or exec.

apptainer run docker://python:alpine python hello.py

Currently you will only get the local home (/home/anders.linux), but not the remote home (/home/anders)

/usr/local/bin/python: can't open file '/home/anders.linux/hello.py': [Errno 2] No such file or directory

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One possibility would be to use -H $HOME.

But it doesn't work well with --fakeroot.

EDIT: Use the APPTAINER_HOME for this.

$ apptainer.lima run docker://python:alpine python hello.py
INFO:    Using cached SIF image
Hello, World!

[AkihiroSuda]

Thanks