Ubuntu 16 Docker install script

docker.sh

#!/bin/bash

TMP_DIR=`mktemp --directory`
LIST_FILE=$TMP_DIR/docker.list
DOCKER_GROUP="docker"


apt-get update
apt-get install apt-transport-https ca-certificates
apt-key adv --keyserver hkp://p80.pool.sks-keyservers.net:80 --recv-keys 58118E89F3A912897C070ADBF76221572C52609D

cat << EOF > $LIST_FILE
deb https://apt.dockerproject.org/repo ubuntu-xenial main
EOF

chmod 644 $LIST_FILE
cp $LIST_FILE /etc/apt/sources.list.d/

apt-get update
apt-get purge lxc-docker
apt-cache policy docker-engine
apt-get install linux-image-extra-$(uname -r) linux-image-extra-virtual
apt-get install docker-engine
service docker start

# Create a Docker group if not exists
/bin/egrep  -i "^${DOCKER_GROUP}:" /etc/group
if [ $? -eq 0 ]; then
   echo "Docker's group exists"
else
   # groupadd docker
fi
usermod -aG docker $USER

rm $LIST_FILE
rm -R $TMP_DIR