#!/bin/sh
# Init script for logstash
# Maintained by Elasticsearch
# Generated by pleaserun.
# Implemented based on LSB Core 3.1:
# * Sections: 20.2, 20.3
#
### BEGIN INIT INFO
# Provides: logstash
# Required-Start: $remote_fs $syslog
# Required-Stop: $remote_fs $syslog
# Default-Start: 2 3 4 5
# Default-Stop: 0 1 6
# Short-Description:
# Description: Starts Logstash as a daemon.
### END INIT INFO

PATH=/sbin:/usr/sbin:/bin:/usr/bin
export PATH

if [ `id -u` -ne 0 ]; then
echo "You need root privileges to run this script"
exit 1
fi

name=logstash
pidfile="/var/run/$name.pid"

LS_USER=root
LS_GROUP=root
LS_HOME=/var/lib/logstash
LS_HEAP_SIZE="1000m"
LS_LOG_DIR=/var/log/logstash
LS_LOG_FILE="${LS_LOG_DIR}/$name.log"
LS_CONF_DIR=/etc/logstash/conf.d/
LS_OPEN_FILES=16384
LS_NICE=19
LS_OPTS=""

[ -r /etc/default/$name ] && . /etc/default/$name
[ -r /etc/sysconfig/$name ] && . /etc/sysconfig/$name

program=/usr/share/logstash/bin/logstash
args="-f ${LS_CONF_DIR} -l ${LS_LOG_FILE} ${LS_OPTS}"

start() {

LS_JAVA_OPTS="${LS_JAVA_OPTS} -Djava.io.tmpdir=${LS_HOME}"
HOME=${LS_HOME}
export PATH HOME LS_HEAP_SIZE LS_JAVA_OPTS LS_USE_GC_LOGGING

# chown doesn't grab the suplimental groups when setting the user:group - so we have to do it for it.
# Boy, I hope we're root here.
SGROUPS=$(id -Gn "$LS_USER" | tr " " "," | sed 's/,$//'; echo '')

if [ ! -z $SGROUPS ]
then
EXTRA_GROUPS="--groups $SGROUPS"
fi

# set ulimit as (root, presumably) first, before we drop privileges
ulimit -n ${LS_OPEN_FILES}

# Run the program!
nice -n ${LS_NICE} chroot --userspec $LS_USER:$LS_GROUP $EXTRA_GROUPS / sh -c "
cd $LS_HOME
ulimit -n ${LS_OPEN_FILES}
exec \"$program\" $args
" > "${LS_LOG_DIR}/$name.stdout" 2> "${LS_LOG_DIR}/$name.err" &

# Generate the pidfile from here. If we instead made the forked process
# generate it there will be a race condition between the pidfile writing
# and a process possibly asking for status.
echo $! > $pidfile

echo "$name started."
return 0
}

stop() {
# Try a few times to kill TERM the program
if status ; then
pid=`cat "$pidfile"`
echo "Killing $name (pid $pid) with SIGTERM"
kill -TERM $pid
# Wait for it to exit.
for i in 1 2 3 4 5 ; do
echo "Waiting $name (pid $pid) to die..."
status || break
sleep 1
done
if status ; then
if [ "$KILL_ON_STOP_TIMEOUT" -eq 1 ] ; then
echo "Timeout reached. Killing $name (pid $pid) with SIGKILL. This may result in data loss."
kill -KILL $pid
echo "$name killed with SIGKILL."
else
echo "$name stop failed; still running."
fi
else
echo "$name stopped."
fi
fi
}

status() {
if [ -f "$pidfile" ] ; then
pid=`cat "$pidfile"`
if kill -0 $pid > /dev/null 2> /dev/null ; then
# process by this pid is running.
# It may not be our pid, but that's what you get with just pidfiles.
# TODO(sissel): Check if this process seems to be the same as the one we
# expect. It'd be nice to use flock here, but flock uses fork, not exec,
# so it makes it quite awkward to use in this case.
return 0
else
return 2 # program is dead but pid file exists
fi
else
return 3 # program is not running
fi
}

force_stop() {
if status ; then
stop
status && kill -KILL `cat "$pidfile"`
fi
}

case "$1" in
start)
status
code=$?
if [ $code -eq 0 ]; then
echo "$name is already running"
else
start
code=$?
fi
exit $code
;;
stop) stop ;;
force-stop) force_stop ;;
status)
status
code=$?
if [ $code -eq 0 ] ; then
echo "$name is running"
else
echo "$name is not running"
fi
exit $code
;;
restart)

stop && start
;;
*)
echo "Usage: $SCRIPTNAME {start|stop|force-stop|status|restart}" >&2
exit 3
;;
esac

exit $?