node-init-general

#!/bin/bash
#
# chkconfig: 35 90 12
# description: Start node apps.
#

# This grabs the name of the init script. The weird string match handles
# the case when the init script is called on boot as /etc/rcN/S90[name].
INIT_SCRIPT_BASENAME=`basename $0`
SERVICE=${INIT_SCRIPT_BASENAME#S90}

#############################################################################
# CONFIGURATION BEGIN
#############################################################################

# These options can all be overridden in /etc/sysconfig/[name of init script]
# eg., if your init script is /etc/init.d/foo, then /etc/sysconfig/foo.
# This allows this one init script to be reused multiple times.

# Full path to the app file you want to launch.
APP=/full/path/to/app.js

# Name of the file to log all console output from the node process. You
# should be able to use /dev/null here if you just want to throw it away.
LOGFILE=/full/path/to/log/file

# Any arguments you want to pass to the app.
APP_ARGS=""

# Full path to the node executable. The 'which' program can usually locate
# this for you, but you can also hard code this if necessary.
NODE=`which node`

# User to run the process as.
NODE_USER="node"

# Setting for the NODE_ENV environment variable.
NODE_ENV="development"

# Name of pid/lock files -- these are sensible defaults.
PIDFILE=/var/run/${SERVICE}.pid
LOCKFILE=/var/lock/subsys/${SERVICE}

# How many seconds to wait before checking if the node process has started
# successfully.
START_CHECK_LOOPS=5
STOP_TIMEOUT=10

#############################################################################
# CONFIGURATION END
#############################################################################

DAEMON_ARGS="--check $SERVICE --pidfile $PIDFILE"

# Load the function library.
 . /etc/init.d/functions

# Override defaults with custom settings.
if [ -f /etc/sysconfig/${SERVICE} ]; then
  . /etc/sysconfig/${SERVICE}
fi

RETVAL=0

rh_status() {
  status -p $PIDFILE $SERVICE
}

rh_status_quiet() {
  rh_status >/dev/null 2>&1
}

start() {
  # Trim the whitespace from the command, needed for pgrep below
  local NODE_COMMAND="$(echo -e "$NODE $APP $APP_ARGS" | sed -e 's/^[[:space:]]*//' -e 's/[[:space:]]*$//')"
  if [ "$NODE_USER" != "root" ]; then
    DAEMON_ARGS="$DAEMON_ARGS --user $NODE_USER"
  fi
  # Starts the node app as a background process.
  echo -n "Starting ${SERVICE}: "
  daemon $DAEMON_ARGS NODE_ENV="${NODE_ENV}" $NODE_COMMAND >> $LOGFILE 2>&1 &
  # Writing the pidfile on behalf of the node process requires avoiding a race
  # condition with the daemon call. Pausing here allows the call to complete
  # before the pidfile is written.
  sleep 1
  # Also, unfortunately, the $! bash variable doesn't contain the proper pid
  # needed. This strategy should be pretty safe, since running the same app
  # with the same arguments using this init script doesn't make much sense.
  # Certain special characters in $APP_ARGS might break this functionality, not
  # tested extensively.
  local pid=`pgrep -f -n "$NODE_COMMAND"`
  if [ -n "$pid" ]; then
    echo $pid > $PIDFILE
    local count=1
    while true; do
      rh_status_quiet
      RETVAL=$?
      if [ $RETVAL -eq 0 ]; then
        touch $LOCKFILE && success || failure
        break
      else
        if [ $count -gt $START_CHECK_LOOPS ]; then
          rm -f $PIDFILE
          failure
          break
        else
          ((count++))
        fi
      fi
      sleep 1
    done
  else
    failure
  fi
  echo
}

stop() {
  echo -n "Stopping ${SERVICE}: "
  killproc -p $PIDFILE -d $STOP_TIMEOUT $SERVICE -INT
  RETVAL=$?                    
  if [ $RETVAL = 0 ]; then
    cleanup && success || failure
  else
    failure
  fi
  echo
}

restart() {
  stop
  start
}

cleanup() {
  rm -f $PIDFILE && rm -f $LOCKFILE
  return $?
}

case "$1" in
  start)
    rh_status_quiet && exit 0
    start
    ;;
  stop)
    rh_status_quiet
    if [ $? -eq 0 ]; then
      stop
    else
      cleanup && exit 0
    fi
    ;;
  restart)
    restart
    ;;
  status)
    rh_status
    ;;
  *)
    echo $"Usage: $0 {start|stop|restart|status}"
    RETVAL=1
esac

exit $RETVAL