core/rest/bin/rest-daemon.sh

#!/usr/bin/env bash
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#
# Runs a REST command as a daemon.
#
# Environment Variables
#
#   REST_CONF_DIR   Alternate REST conf dir. Default is ${REST_HOME}/conf.
#   REST_LOG_DIR    Where log files are stored.  PWD by default.
#   REST_PID_DIR    The pid files are stored. ${REST_HOME}/tmp by default.
#   REST_IDENT_STRING   A string representing this instance. $USER by default
#   REST_NICENESS The scheduling priority for daemons. Defaults to 0.
#

usage="Usage: rest-daemon.sh [--config <conf-dir>]\
 (start|stop|restart) <rest-command> \
 <args...>"

# if no args specified, show usage
if [ $# -le 1 ]; then
  echo $usage
  exit 1
fi

bin=`dirname "${BASH_SOURCE-$0}"`
bin=`cd "$bin">/dev/null; pwd`

. "$bin"/rest-config.sh

# get arguments
startStop=$1
shift

command=$1
shift

instance=$1
case $instance in
    ''|*[!0-9]*) instance=1 ;; #bad
    *) ;; #good
esac

rest_rotate_log ()
{
    log=$1;
    num=5;
    if [ -n "$2" ]; then
    num=$2
    fi
    if [ -f "$log" ]; then # rotate logs
    while [ $num -gt 1 ]; do
        prev=`expr $num - 1`
        [ -f "$log.$prev" ] && mv -f "$log.$prev" "$log.$num"
        num=$prev
    done
    mv -f "$log" "$log.$num";
    fi
}

wait_until_done ()
{
    p=$1
    cnt=${REST_SLAVE_TIMEOUT:-300}
    origcnt=$cnt
    while kill -0 $p > /dev/null 2>&1; do
      if [ $cnt -gt 1 ]; then
        cnt=`expr $cnt - 1`
        sleep 1
      else
        echo "Process did not complete after $origcnt seconds, killing."
        kill -9 $p
        exit 1
      fi
    done
    return 0
}

# get log directory
if [ "$REST_LOG_DIR" = "" ]; then
  export REST_LOG_DIR="$REST_HOME/logs"
fi
mkdir -p "$REST_LOG_DIR"

if [ "$REST_PID_DIR" = "" ]; then
  REST_PID_DIR="$REST_HOME/tmp"
fi

#if [ "$REST_IDENT_STRING" = "" ]; then
  export REST_IDENT_STRING="$USER-$instance"
#fi

# Some variables
# Work out java location so can print version into log.
if [ "$JAVA_HOME" != "" ]; then
  #echo "run java in $JAVA_HOME"
  JAVA_HOME=$JAVA_HOME
fi
if [ "$JAVA_HOME" = "" ]; then
  echo "Error: JAVA_HOME is not set."
  exit 1
fi
JAVA=$JAVA_HOME/bin/java
export REST_LOG_PREFIX=rest-$REST_IDENT_STRING-$command-$HOSTNAME
export REST_LOGFILE=$REST_LOG_PREFIX.log
export REST_ROOT_LOGGER="INFO,DRFA"
export REST_SECURITY_LOGGER="INFO,DRFAS"
logout=$REST_LOG_DIR/$REST_LOG_PREFIX.out  
loggc=$REST_LOG_DIR/$REST_LOG_PREFIX.gc
loglog="${REST_LOG_DIR}/${REST_LOGFILE}"
pid=$REST_PID_DIR/rest-$REST_IDENT_STRING-$command.pid

if [ "$REST_USE_GC_LOGFILE" = "true" ]; then
  export REST_GC_OPTS=" -Xloggc:${loggc}"
fi

# Set default scheduling priority
if [ "$REST_NICENESS" = "" ]; then
    export REST_NICENESS=0
fi

case $startStop in

  (start)
    mkdir -p "$REST_PID_DIR"
    if [ -f $pid ]; then
      if kill -0 `cat $pid` > /dev/null 2>&1; then
        echo $command  `cat $pid`.  Stop it first.
        exit 1
      fi
    fi

    rest_rotate_log $logout
    rest_rotate_log $loggc
    echo starting $command, logging to $logout
    nohup nice -n $REST_NICENESS "$REST_HOME"/bin/rest \
        --config "${REST_CONF_DIR}" \
        $command "$@" $startStop > "$logout" 2>&1 < /dev/null &
    echo $! > $pid
    sleep 1; head "$logout"
    ;;

  (stop)
    if [ -f $pid ]; then
      # kill -0 == see if the PID exists 
      if kill -0 `cat $pid` > /dev/null 2>&1; then
        echo -n stopping $command
        echo "`date` Terminating $command" >> $loglog
        kill `cat $pid` > /dev/null 2>&1
        while kill -0 `cat $pid` > /dev/null 2>&1; do
          echo -n "."
          sleep 1;
        done
        rm $pid
        echo
      else
        retval=$?
        echo no $command to stop because kill -0 of pid `cat $pid` failed with status $retval
      fi
    else
      echo no $command to stop because no pid file $pid
    fi
    ;;

  (restart)
    thiscmd=$0
    args=$@
    # stop the command
    $thiscmd --config "${REST_CONF_DIR}" stop $command $args &
    wait_until_done $!
    # wait a user-specified sleep period
    sp=${REST_RESTART_SLEEP:-3}
    if [ $sp -gt 0 ]; then
      sleep $sp
    fi
    # start the command
    $thiscmd --config "${REST_CONF_DIR}" start $command $args &
    wait_until_done $!
    ;;

  (*)
    echo $usage
    exit 1
    ;;

esac