Little snippet to print the mappings between docker volume names and their parent containers

docker-volumes-by-containers.md

Print Docker Volumes by Container

I have quite a few stopped containers. I would like to delete the volumes belonging to some of them. Docker has a volume prune command that will delete ALL the volumes. Annoyingly, it does not have a --dry-run options o you're taking a shot in the dark. I made this snippet to help gain more context.

#!/bin/bash 
for name in $(docker ps -a |awk 'NR>1{print $NF}'); do 
    vols=$(docker inspect $name | jq '.[].Mounts[]|select(.Type=="volume")'|jq -r .Name|tr '\n' ' '); 
    printf "%s=( %s );\n" "$name" "$vols"; 
done

Let's take a look at it's output

app_1_container_1=( 50677fe74273f64a88c387b7fedb8d7618a6b427227a893a437c0bfa94543330 3493f57091af2809df256be943b5744eec96ae72c1599043ca952e2b138d7f15  );
app_1_container_2=(  );
app_2_container_1=( a8271b04072b3c4a00d5032b0d39203ddbbe97348553cd5217d2d47d39b2582e 8b01887243f24670abdd88ab29696073c7a0453416aad132dc6ad5a24d5d85af  );
app_2_container_2=(  );
app_3_container_1=( 670c5e5e70822b063448f62ccea4d466680290d1f9bd32284f6daa67a4959043 aa33946a502fe91130dfc4495724771a210516ddad7b2b056c08c79d81fcd713  );
app_4_container_1=( 1167fa48cb355511664ef30b4f1fee048d007b995d003d63871669d282d06d23 93edc0d14b1f01113e8801b8e4abaa1cf5eb60e3de243161fec2d984a3e9123a  );
app_4_container_2=(  );

This makes clean up easier. Now I can just stash away the volumes I want and run docker volume prune.