examples/init.sh

   1 #!/bin/sh
   2 # To the extent possible under law, Eric Wong has waived all copyright and
   3 # related or neighboring rights to this examples
   4 set -e
   5 ### BEGIN INIT INFO
   6 # Provides:          yahns
   7 # Required-Start:    $local_fs $network
   8 # Required-Stop:     $local_fs $network
   9 # Default-Start:     2 3 4 5
  10 # Default-Stop:      0 1 6
  11 # Short-Description: Start/stop yahns Ruby app server
  12 ### END INIT INFO
  13
  14 # Feel free to change any of the following variables for your app:
  15 TIMEOUT=${TIMEOUT-60}
  16 APP_ROOT=/home/x/my_app/current
  17 PID=$APP_ROOT/tmp/pids/yahns.pid
  18 CMD="/usr/bin/yahns -D -c $APP_ROOT/config/yahns.rb"
  19 INIT_CONF=$APP_ROOT/config/init.conf
  20 UPGRADE_DELAY=${UPGRADE_DELAY-2}
  21 action="$1"
  22 set -u
  23
  24 test -f "$INIT_CONF" && . $INIT_CONF
  25
  26 OLD="$PID.oldbin"
  27
  28 cd $APP_ROOT || exit 1
  29
  30 sig () {
  31         test -s "$PID" && kill -$1 $(cat $PID)
  32 }
  33
  34 oldsig () {
  35         test -s "$OLD" && kill -$1 $(cat $OLD)
  36 }
  37
  38 case $action in
  39 start)
  40         sig 0 && echo >&2 "Already running" && exit 0
  41         $CMD
  42         ;;
  43 stop)
  44         sig QUIT && exit 0
  45         echo >&2 "Not running"
  46         ;;
  47 force-stop)
  48         sig TERM && exit 0
  49         echo >&2 "Not running"
  50         ;;
  51 restart|reload)
  52         sig HUP && echo reloaded OK && exit 0
  53         echo >&2 "Couldn't reload, starting '$CMD' instead"
  54         $CMD
  55         ;;
  56 upgrade)
  57         if oldsig 0
  58         then
  59                 echo >&2 "Old upgraded process still running with $OLD"
  60                 exit 1
  61         fi
  62
  63         cur_pid=
  64         if test -s "$PID"
  65         then
  66                 cur_pid=$(cat $PID)
  67         fi
  68
  69         if test -n "$cur_pid" &&
  70                         kill -USR2 "$cur_pid" &&
  71                         sleep $UPGRADE_DELAY &&
  72                         new_pid=$(cat $PID) &&
  73                         test x"$new_pid" != x"$cur_pid" &&
  74                         kill -0 "$new_pid" &&
  75                         kill -QUIT "$cur_pid"
  76         then
  77                 n=$TIMEOUT
  78                 while kill -0 "$cur_pid" 2>/dev/null && test $n -ge 0
  79                 do
  80                         printf '.' && sleep 1 && n=$(( $n - 1 ))
  81                 done
  82                 echo
  83
  84                 if test $n -lt 0 && kill -0 "$cur_pid" 2>/dev/null
  85                 then
  86                         echo >&2 "$cur_pid still running after $TIMEOUT seconds"
  87                         exit 1
  88                 fi
  89                 exit 0
  90         fi
  91         echo >&2 "Couldn't upgrade, starting '$CMD' instead"
  92         $CMD
  93         ;;
  94 reopen-logs)
  95         sig USR1
  96         ;;
  97 *)
  98         echo >&2 "Usage: $0 <start|stop|restart|upgrade|force-stop|reopen-logs>"
  99         exit 1
 100         ;;
 101 esac