Inspecting the metadata of the container

Online documentation

$ singularity inspect [inspect options...] <image path>

Inspect will show you labels, environment variables, apps and scripts associated with the image determined by the flags you pass.

Let's inspect our containers.

-d - show the Singularity recipe file that was used to generate the image

$ singularity inspect -d lolcow.sif

BootStrap: docker
From: ubuntu:16.04

%post
  apt-get -y update
  apt-get -y install fortune cowsay lolcat

%environment
  export LC_ALL=C
  export PATH=/usr/games:$PATH

%runscript
  fortune | cowsay | lolcat

-e - show the environment settings for the image

$ singularity inspect -e lolcow.sif

=== /.singularity.d/env/10-docker2singularity.sh ===
#!/bin/sh
export PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"

=== /.singularity.d/env/90-environment.sh ===
#!/bin/sh
# Custom environment shell code should follow


  export LC_ALL=C
  export PATH=/usr/games:$PATH

-r - show the runscript for the image

$ singularity inspect -r lolcow.sif

#!/bin/sh

  fortune | cowsay | lolcat

Note

Do not assume that the content of the script will give you all the information. Just test with an image you have downloaded from docker://

docker://

singularity inspect -d wttr.sif

bootstrap: docker
from: dctrud/wttr

Check the runscript.