+#You must have $DOCKER_SETUP_USER env var to set up the container's user.
+#This script must be run as ROOT, on container start.
+# Protip: Use sudo/sudoers to enable calling this easily:
+# echo "${user} ALL=NOPASSWD:SETENV: /app/setup/*" >> /etc/sudoers
+# sudo -E /app/setup/setupDockerMount.sh
+DOCKER_USER=$DOCKER_SETUP_USER
+DOCKER_BIN=/usr/bin/docker
+DOCKER_SOCKET=/var/run/docker.sock
+DOCKER_GROUP=$(ls -al $DOCKER_SOCKET | awk '{print $4}')
+DOCKER_GID=$(ls -aln $DOCKER_SOCKET | awk '{print $4}')
+HAS_GROUP=$(getent group $DOCKER_GID)
+USER_NOT_IN_GROUP=$(id -nG "$DOCKER_USER" | grep -qw "$DOCKER_GROUP")
+DOCKER_BROKEN=$($DOCKER_BIN 2>&1 | grep -E 'not found|cannot open shared')
+#Make sure we're mounted with socket!
+if [[ ! -S $DOCKER_SOCKET ]]
+ echo "Missing: $DOCKER_SOCKET!"
+#Make sure we're mounted with binary!
+if [[ ! -f $DOCKER_BIN ]]
+ echo "Missing: $DOCKER_BIN!"
+ echo "Exists: $DOCKER_BIN"
+#Make sure we're mounted with executable!
+if [[ ! -x $DOCKER_BIN ]]
+ echo "Not Executable: $DOCKER_BIN!"
+#Test if dynamic linked objects for binary are missing
+if [[ ! -z "$DOCKER_BROKEN" ]]
+ echo "Inoperable: $DOCKER_BIN"
+ echo -e "\t\tEnsure all linked objects are volume mounted as well (use: ldd $(which docker))."
+ echo "Creating 'docker' group: $DOCKER_GID"
+ addgroup --gid $DOCKER_GID docker
+#Add User to Group if not already in it
+if [[ ! $USER_NOT_IN_GROUP ]]
+ echo "Adding '$DOCKER_USER' to group: $DOCKER_GROUP($DOCKER_GID)"
+ echo -e "\tNote: The *name* may not be right, but the GID should be!"
+ adduser $DOCKER_USER $DOCKER_GROUP
