Support mounting anonymous volume

[mzagozen]

The docker run ... -v /path/to/dir syntax creates an anonymous volume and mounts it to the given destination path in the container.

[hellt]

Thanks @mzagozen

can you add a bit of a context how are you using this anon volume so that we can provide some hints in the docs?

[codecov]

Codecov Report

Attention: 10 lines in your changes are missing coverage. Please review.

Comparison is base (30dfa30) 51.82% compared to head (a2b9ca6) 51.75%.
Report is 3 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1853      +/-   ##
==========================================
- Coverage   51.82%   51.75%   -0.08%     
==========================================
  Files         148      148              
  Lines       14548    14560      +12     
==========================================
- Hits         7539     7535       -4     
- Misses       6176     6189      +13     
- Partials      833      836       +3     

Files	Coverage Δ
clab/config.go	65.83% <0.00%> (-0.75%)	⬇️
types/bind.go	45.71% <40.00%> (-4.29%)	⬇️

... and 1 file with indirect coverage changes

[mzagozen]

Sure, we have topologies that include a Cisco NSO container based on nso-docker, like so:

topology:
    nso:
      kind: linux
      image: ${NSO_IMAGE}
      binds:
        - /var/opt/ncs/packages

The path /var/opt/ncs/packages is the NSO package load path - where it loads user code from. We have an existing development workflow where we use this anonymous volume to then update the code (NSO packages) in the running NSO container by running a sidecar container for compilation. This sidecar attaches to the anonymous volume mounted in the NSO container with the command docker run --volumes-from ${NSO_CNT} ...

From https://gitlab.com/nso-developer/nso-docker/-/blob/master/skeletons/system/testenvs/testenv-common.mk?ref_type=heads#L66:

docker run -t --rm -v $(PROJECT_DIR):/src --volumes-from $${NSO} $(NSO_IMAGE_PATH)cisco-nso-dev:$(NSO_VERSION) bash -lc 'rsync -aEim -- ...

[hellt]

thanks