タグに紐づくdockerイメージとインスタンスを削除するシェルスクリプト

#!/bin/bash

#
# タグに紐づくdockerイメージとインスタンスを削除する
#

export TAG=$1
if [ -z ${TAG} ];then
        export COMMAND=`basename $0`
        echo "usage: ${COMMAND} <tag>"
        exit 1
fi

export ACTIVES=`docker ps | grep ${TAG} | wc -l | awk '{print $1}'`
if [ 0 -ne ${ACTIVES} ];then
        echo "active instances:"
        docker ps | grep ${TAG}
        echo ""
        echo "Abort."
        exit 1
fi

docker ps -a | grep ${TAG} | awk '{print $1}' | xargs docker rm
docker rmi ${TAG}