path: root/minecraftd.sh

#!/bin/bash

source /etc/conf.d/minecraft || echo "Could not source /etc/conf.d/minecraft"

# You may use this script for any minecraft server of your choice, just alter the config file
SERVER_ROOT="${SERVER_ROOT:-/srv/minecraft}"
BACKUPPATH="${BACKUPPATH:-/srv/minecraft/backup}"
LOGPATH="${LOGPATH:-/srv/minecraft/logs}"
WORLDPATHS="${WORLDPATHS:-/srv/minecraft/world}"
KEEP_BACKUPS="${KEEP_BACKUPS:-10}"
MC_USER="${MC_USER:-minecraft}"
MAIN_JAR="${MAIN_JAR:-minecraft_server.jar}"
SESSION_NAME="${SESSION_NAME:-minecraft}"

# Specify system parameters for the minecraft server
MINHEAP="${MINHEAP:-512M}"
MAXHEAP="${MAXHEAP:-1024M}"
THREADS="${THREADS:-1}"
JAVA_PARMS="${JAVA_PARMS:-"-Xmx${MAXHEAP} -Xms${MINHEAP} -XX:ParallelGCThreads=${THREADS}"}"

# Check for sudo rigths
if [ $(sudo whoami) != "root" ]; then
	echo "You must have sudo access in order to use this script."
	exit 1
fi

# Pipe any given argument to the minecraft server console
mc_command() {
	sudo -u ${MC_USER} screen -S ${SESSION_NAME} -X stuff "`printf \"$*\r\"`"
}

# Start the server if it is not already running
server_start() {
	sudo -u ${MC_USER} screen -S ${SESSION_NAME} -Q select . > /dev/null
	if [ $? -eq 0 ]; then
		echo "A screen ${SESSION_NAME} session is already running. Please close it first."
	else
		echo -en "Starting server... "
		sudo -u ${MC_USER} screen -dmS ${SESSION_NAME} /bin/bash -c "cd ${SERVER_ROOT}; java ${JAVA_PARMS} -jar ${SERVER_ROOT}/${MAIN_JAR} nogui"
		echo -e "\e[39;1m done\e[0m"
	fi
}

# Stop the server gracefully by saving everything prior and warning the users
server_stop() {
	sudo -u ${MC_USER} screen -S ${SESSION_NAME} -Q select . > /dev/null
	if [ $? -eq 0 ]; then
		mc_command save-all
		mc_command say "Server is going down in 10 seconds! HURRY UP WITH WATHEVER YOU ARE DOING!" # Warning the users
		echo -en "Server is going down in... "
		for i in $(seq 1 10);
		do
			mc_command say "down in... $(expr 10 - $i)"
			echo -n " $(expr 10 - $i)"
			sleep 1
		done
		mc_command stop
		echo -e "\e[39;1m done\e[0m"
	else
		echo "The corresponding screen session for ${SESSION_NAME} was already dead."
	fi
}

# Print whether the server is running and if so give some information about memory usage and threads
server_status() {
	sudo -u ${MC_USER} screen -S ${SESSION_NAME} -Q select . > /dev/null
	if [ $? -eq 0 ]; then
		echo -e "Status:\e[39;1m running\e[0m"

		# Calculating memory usage
		for p in $(sudo -u ${MC_USER} pgrep -f ${MAIN_JAR}); do
			ps -p$p -O rss | tail -n1;
		done | gawk '{ count ++; sum += $2 }; END {count --; print "Number of processes =", count, "(screen, bash,", count-2, "x java)"; print "Total memory usage =", sum/1024, "MB" ;};'
	else
		echo -e "Status:\e[39;1m stopped\e[0m"
	fi
}

# Restart the complete server by shutting it down and starting it again
server_restart() {
	sudo -u ${MC_USER} screen -S ${SESSION_NAME} -Q select . > /dev/null
	if [ $? -eq 0 ]; then
		server_stop
		sleep 0.1
		server_start
	else
		server_start
	fi
}

# Backup the directories specified in $WORLDPATHS
backup_files() {
	which tar &> /dev/null
	if [ $? -ne 0 ]; then
		echo "The tar binaries are needed for a backup."
		exit 2
	fi

	echo "Starting backup..."
	FILE="`date +%Y%m%d%H%M%S`.tar.gz"
	sudo -u ${MC_USER} mkdir -p ${BACKUPPATH}
	sudo -u ${MC_USER} screen -S ${SESSION_NAME} -Q select . > /dev/null
	if [ $? -eq 0 ]; then
		mc_command save-off
		mc_command save-all
		sync && wait
		sudo -u ${MC_USER} tar -czf ${BACKUPPATH}/${FILE} --totals ${WORLDPATHS} 2>&1 | grep -v "tar: Removing leading "
		mc_command save-on
	else
		sudo -u ${MC_USER} tar -czf ${BACKUPPATH}/${FILE} --totals ${WORLDPATHS} 2>&1 | grep -v "tar: Removing leading "
	fi
	echo -e "\e[39;1mbackup completed\e[0m\n"

	echo -n "Only keeping the last ${KEEP_BACKUPS} backups and removing the other ones..."
	BACKUP_COUNT=$(for f in ${BACKUPPATH}/[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]*; do echo $f; done | wc -l)
	if [ $(expr ${BACKUP_COUNT} - ${KEEP_BACKUPS}) -gt 0 ]; then
		sudo -u ${MC_USER} rm $(for f in ${BACKUPPATH}/[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]*; do echo $f; done | head -n$(expr ${BACKUP_COUNT} - ${KEEP_BACKUPS}))
		echo -e "\e[39;1m done\e[0m ($(expr ${BACKUP_COUNT} - ${KEEP_BACKUPS}) backup(s) pruned)"
	else
		echo -e "\e[39;1m done\e[0m (no backups pruned)"
	fi
}

# Run the given comman at the minecraft server console
server_command() {
	if [ $# -lt 1 ]; then
		echo "No server command specified. Try 'help' for a list of commands."
		exit 1
	fi

	sudo -u ${MC_USER} screen -S ${SESSION_NAME} -Q select . > /dev/null
	if [ $? -eq 0 ]; then
		mc_command "$@" &
		tailf --pid=$! -n 0 ${LOGPATH}/latest.log &
	else
		echo "There is no ${SESSION_NAME} session to connect to."
	fi
}

# Enter the screen minecraft session
server_console() {
	sudo -u ${MC_USER} screen -S ${SESSION_NAME} -Q select . > /dev/null
	if [ $? -eq 0 ]; then
		sudo -u ${MC_USER} screen -S ${SESSION_NAME} -rx
	else
		echo "There is no ${SESSION_NAME} session to connect to."
	fi
}

# Help function, no arguments required
help() {
	cat <<- 'EOF'
	This script was design to easily control any minecraft server. Quite every parameter for a given
	minecraft server derivative can be altered by editing the variables in the configuration file.

	Usage: minecraftd {start|stop|status|backup|command <command>|console}
	    start                Start the minecraft server
	    stop                 Stop the minecraft server
	    restart              Restart the minecraft server
	    status               Print some status information
	    backup               Backup the world data
	    command <command>    Run the given comman at the minecraft server console
	    console              Enter the server console through a screen session

	Copyright (c) Gordian Edenhofer <gordian.edenhofer@gmail.com>
	EOF
}

case "$1" in
	start)
	server_start
	;;

	stop)
	server_stop
	;;

	status)
	server_status
	;;

	restart)
	server_restart
	;;

	console)
	server_console
	;;

	command)
	server_command "${@:2}"
	;;

	backup)
	backup_files
	;;

	*|-h|--help)
	help
esac

exit 0