docker-volume-backup/docker-volume-backup.sh

#!/bin/bash
# Just backups volumes of running containers
# If rsync stucks consider:
# @see https://stackoverflow.com/questions/20773118/rsync-suddenly-hanging-indefinitely-during-transfers
#
backup_time="$(date '+%Y%m%d%H%M%S')";
backups_folder="/Backups/";
repository_name="$(cd "$(dirname "$(readlink -f "${0}")")" && basename `git rev-parse --show-toplevel`)";
machine_id="$(sha256sum /etc/machine-id | head -c 64)";
backup_repository_folder="$backups_folder$machine_id/$repository_name/";
for volume_name in $(docker volume ls --format '{{.Name}}');
do
  echo "start backup routine: $volume_name";
  containers="$(docker ps --filter volume="$volume_name" --format '{{.Names}}')";
  containers_array=($containers)
  container=${containers_array[0]}
  if [ -z "$containers" ]
    then
      echo "skipped due to no running containers using this volume."
    else
      echo "stop containers:" && docker stop $containers
      for source_path in $(docker inspect --format "{{ range .Mounts }}{{ if eq .Type \"volume\"}}{{ if eq .Name \"$volume_name\"}}{{ println .Destination }}{{ end }}{{ end }}{{ end }}" "$container");
      do
        destination_path="$backup_repository_folder""latest/$volume_name";
        raw_destination_path="$destination_path/raw"
        prepared_destination_path="$destination_path/prepared"
        log_path="$backup_repository_folder""log.txt";
        backup_dir_path="$backup_repository_folder""diffs/$backup_time/$volume_name";
        raw_backup_dir_path="$backup_dir_path/raw";
        prepared_backup_dir_path="$backup_dir_path/prepared";
        if [ -d "$destination_path" ]
          then
            echo "backup volume: $volume_name";
          else
            echo "first backup volume: $volume_name"
            mkdir -vp "$raw_destination_path";
            mkdir -vp "$raw_backup_dir_path";
            mkdir -vp "$prepared_destination_path";
            mkdir -vp "$prepared_backup_dir_path";
        fi
        docker run --rm --volumes-from "$container" -v "$backups_folder:$backups_folder" "kevinveenbirkenbach/alpine-rsync" sh -c "
        rsync -abP --delete --delete-excluded --log-file=$log_path --backup-dir=$raw_backup_dir_path '$source_path/' $raw_destination_path";
        echo "start containers:" && docker start $containers;
      done
  fi
  echo "end backup routine: $volume_name";
done