version.sh

#!/usr/bin/env bash
if [ -n "$PROJECT_VERSION" ]; then
    # use env variable PROJECT_VERSION if defined
    echo $PROJECT_VERSION
elif ! [ -x "$(command -v git)" ] || ! [ -d .git ]; then
	# git is not installed, or not in a git repo
    echo '0-unknown-version'
else
	# fetch all tags silently
	git fetch --tags --quiet > /dev/null 2> /dev/null
	# get human readable commit id from git
	git describe --tags --always --dirty | sed 's/^v//'
fi