asyd.sh

#!/bin/sh

# EXIT CODES
# 0 - Script ran successfully
# 1 - Illegal or no arguments specified
# 2 - Failed to start the daemon
# 3 - Failed to kill the daemon
# 4 - Failed to restart the daemon
# 128+ - Amount of ASYD processes running (subtract 128 to get the real number)

self="${0}"
cmd="${1}"
pidfile=".asyd.pid"
stopmaxwaititerations=60 # 30 seconds (0.5 seconds per iteration)
killmaxwaititerations=10 # 5 seconds
stopwaititerationsleep=0.5
killwaititerationsleep=0.5

case "${cmd}" in
	start)
		echo -n "Waiting for ASYD to start ..."
		unicorn -c unicorn.conf.rb -D
		pid=$(cat "${pidfile}" 2> /dev/null)
		if ! kill -0 "${pid}" 2> /dev/null; then
			echo " FAILED (daemon not running after start attempt)"
			exit 2
		fi
		echo " done"
		;;
	stop)
		pid=$(cat "${pidfile}" 2> /dev/null)
		if ! kill -0 "${pid}" 2> /dev/null; then
			echo "ASYD not running"
			exit 0
		fi
		kill -3 "${pid}" 2> /dev/null
		echo -n "Waiting for ASYD (${pid}) to be stopped ..."
		i=0
		while kill -0 "${pid}" 2> /dev/null && [ "${i}" != "${stopmaxwaititerations}" ]; do
			echo -n .
			i="$((${i}+1))"
			sleep "${stopwaititerationsleep}"
		done
		if kill -0 "${pid}" 2> /dev/null; then
			echo " FAILED"
			# We failed to gracefully shut down ASYD so we need to forcefully kill it
			echo -n "Waiting for ASYD (${pid}) to be killed ..."
			kill -9 "${pid}" 2> /dev/null
			i=0
			while kill -0 "${pid}" 2> /dev/null && [ "${i}" != "${stopmaxwaititerations}" ]; do
				echo -n .
				i="$((${i}+1))"
				sleep "${killwaititerationsleep}"
			done
			if kill -0 "${pid}" 2> /dev/null; then
				echo " FAILED"
				# We failed to forcefully kill ASYD, something is horribly wrong and the process is not dying!
				exit 3
			fi
		fi
		echo " done"
		;;
	restart)
		sh "${self}" stop && sh "${self}" start || exit 4
		;;
	pid)
		pid=$(cat "${pidfile}" 2> /dev/null)
		echo "${pid}"
		;;
	status)
		echo -n "ASYD is "
		pid=$(cat "${pidfile}" 2> /dev/null)
		kill -0 "${pid}" 2> /dev/null && echo "running" || echo "stopped"
		;;
	count)
		num=$(ps xh -ocommand | grep -E '^ASYD ' | wc -l)
		echo -n "${num}"
		exit "$((128+${num}))"
		;;
	*)
		echo "Usage: ${self} {start|stop|restart|status|pid|count}"
		exit 1
		;;
esac

exit 0