Docker copy from/to volumes. Found on the internets

dcp.sh

#!/bin/bash
SOURCE=$1
DEST=$2

SOURCE_ARR=(${SOURCE//:/ })
DEST_ARR=(${DEST//:/ })


if [[ ${#SOURCE_ARR[@]} -eq 2 && ${#DEST_ARR[@]} -eq 1 ]]; then
        VOL=${SOURCE_ARR[0]}
        VOL_PATH=${SOURCE_ARR[1]}
        HOST_PATH=${DEST_ARR[0]}

        docker container create --name docker_volume_cp -v $VOL:/volume hello-world
        CMD="docker cp docker_volume_cp:/volume/$VOL_PATH $HOST_PATH"
        #echo "$CMD"
        $CMD
        docker rm docker_volume_cp

elif [[ ${#SOURCE_ARR[@]} -eq 1 && ${#DEST_ARR[@]} -eq 2 ]]; then
        VOL=${DEST_ARR[0]}
        VOL_PATH=${DEST_ARR[1]}
        HOST_PATH=${SOURCE_ARR[0]}

        docker container create --name docker_volume_cp -v $VOL:/volume hello-world
        CMD="docker cp $HOST_PATH docker_volume_cp:/volume/$VOL_PATH"
        #echo "$CMD"
        $CMD
        docker rm docker_volume_cp
else
        echo "Usage:"
        echo " volume --> host: $0 VOLUME:VOL_PATH HOST_PATH"
        echo " host --> volume: $0 HOST_PATH VOLUME:VOL_PATH"
fi