serve_here

#!/bin/sh -u

CMD_NOT_FOUND=127
PORT="${1:-8000}"

python3 -m http.server "$PORT"
ev=$?
[ $ev -ne $CMD_NOT_FOUND ] && exit $ev

python2 -m SimpleHTTPServer "$PORT"
ev=$?
[ $ev -ne $CMD_NOT_FOUND ] && exit $ev

# We could use print with future imports, but don't know how long that
# future import will remain around for; writing sys.version_info seems
# more likely to be stable for a Long Time.
version=$(
python <<EOPY
import sys
sys.stdout.write(str(sys.version_info.major))
EOPY
)
ev=$?
[ $ev -eq $CMD_NOT_FOUND ] && exit $ev

case $version in
2)
	echo >&2 'python is python2'
	python -m SimpleHTTPServer "$PORT"
	;;
3)
	echo >&2 'python is python3'
	python -m http.server "$PORT"
	;;
*)
	echo >&2 "Unknown python version '${version}'"
	exit 1
	;;
esac