Debian style unicorn init.d

unicorn

#!/bin/bash
# /etc/init.d/unicorn

# ### BEGIN INIT INFO
# Provides:          unicorn
# Required-Start:    $local_fs $remote_fs $network $syslog
# Required-Stop:     $local_fs $remote_fs $network $syslog
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: unicorn service
# Description: This script will start unicorn installations
#              specified in /etc/unicorn/*.conf
### END INIT INFO

# Modified by oseias at oferreiro.info on https://gist.github.com/oferreiro/8136141
# based on https://gist.github.com/jaygooby/504875
#
###########################################################
## A sample /etc/unicorn/my_app.conf
## 
## RAILS_ENV=production
## RAILS_ROOT=/var/apps/www/my_app/current
## USERNAME=user
##
#
# This configures a unicorn master for your app at /var/apps/www/my_app/current running in
# production mode. It will read config/unicorn/production.rb for further set up. 
#
# You should ensure different ports or sockets are set in each config/unicorn/${RAILS_ENV}.rb
# If you are running more than one master concurrently.
#
# If you call this script without any config parameters, it will attempt to run the
# init command for all your unicorn configurations listed in /etc/unicorn/*.conf
#
# /etc/init.d/unicorn start # starts all unicorns
#
# If you specify a particular config, it will only operate on that one
#
# /etc/init.d/unicorn start my_app # starts only /etc/unicorn/my_app.conf
#

set -e
NAME="unicorn"
CONFIG_PATH=/etc/unicorn
ARGS="$1 $2"
TIMEOUT=30

if ! [[ -d ${CONFIG_PATH} ]]; then 
  echo "Config path ${CONFIG_PATH} does not exists." 
  exit 1
fi

get_pid () {
   [[ -s "${PIDFILE}" ]] && cat "${PIDFILE}"
}

sig () {
  [[ -s "${PIDFILE}" ]] && kill -$1 $(cat "${PIDFILE}")
}

oldsig () {
  [[ -s "${OLD_PIDFILE}" ]] && kill -$1 $(cat "${OLD_PIDFILE}")
}

unicorn_cmd () {
  CURR_USER=$(whoami)
  UNICORN_CMD="bundle exec unicorn -c config/unicorn/${RAILS_ENV}.rb -E ${RAILS_ENV} -D"
  if ! [[ ${USERNAME} ]] || [[ ${USERNAME} == ${CURR_USER} ]]; then
    ${UNICORN_CMD}
  else
    su -c "${UNICORN_CMD}" ${USERNAME}
  fi
}
cmd () {
  case $1 in
    start)
      sig 0 && echo >&2 "Already running" && return 1
      echo "Starting"
      unicorn_cmd
      ;;  
      
    stop)
      sig QUIT && echo "Stopping" && return 0
      echo >&2 "Not running" && return 1
      ;;  
      
    force-stop)
      sig TERM && echo "Forcing a stop" && return 0
      echo >&2 "Not running" && return 1
      ;;  
      
    restart|reload)
      echo -n "Restarting "
      sig HUP && echo "HUP signal sent" && return 0
      echo >&2 "Couldn't reload, starting instead"
      unicorn_cmd
      ;;  
      
    rotate)
      sig USR1 && echo "Rotated logs OK" && return 0
      echo >&2 "Couldn't rotate logs" && return 1
      ;; 
      
    upgrade)
      echo  -n "Upgrading"
      OLD_PID=get_pid
      
      if sig USR2; then
        n=${TIMEOUT}
        echo
        echo -n "Waiting up new master"
        while [[ $n -ge 0 ]]; do
          if [[ -e "${PIDFILE}" ]]  && [[ "${OLD_PID}" -ne "$(get_pid)" ]]  ; then
           	break
          fi
          printf '.' && sleep 1 && n=$(( $n - 1 ))
        done
        
        n=${TIMEOUT}
        echo
        echo -n "Waiting down old master"
        while  [[ -s ${OLD_PIDFILE} ]] && [[ $n -ge 0 ]] ; do
          printf '.' && sleep 1 && n=$(( $n - 1 ))
        done
        
        echo
        if  [[  -s ${OLD_PIDFILE} ]] && [[ $n -lt 0 ]]; then
          echo >&2 "${OLD_PIDFILE} still exists after ${TIMEOUT} seconds"
          oldsig QUIT
          return 1
        fi
        
        if sig 0; then
          return 0
        fi
      fi
      echo >&2 "Couldn't upgrade, starting instead"
      unicorn_cmd
      ;;
  
    *)  
      echo >&2 "Usage: ${NAME} <start|stop|restart|upgrade|rotate|force-stop>"
      exit 0
      ;;  
    esac
}

setup () {
  cd ${RAILS_ROOT} && echo -n "Working in ${RAILS_ROOT}: " || exit 1
  unset PIDFILE
  unset OLD_PIDFILE
  export PIDFILE="${RAILS_ROOT}/tmp/pids/unicorn.pid"
  export OLD_PIDFILE="${PIDFILE}.oldbin"
}

main () {  
  # either run the start/stop/reload/etc command for every config under ${CONFIG_PATH}
  # or just do it for a specific one

  # $1 contains the start/stop/etc command
  # $2 if it exists, should be the specific config we want to act on
  
  if [ $2 ]; then
    CONF=${CONFIG_PATH}/$2.conf
    if  [[ -e ${CONF} ]]; then
      . ${CONF} || exit 1
      setup
      cmd $1
    else
      echo "${NAME}: config file ${CONF} does not exists..."
      exit 1
    fi
  else
    CONFIGS=${CONFIG_PATH}/*.conf
    for CONFIG in ${CONFIGS}; do
      echo -n "Loading ${CONFIG}..."
      if [[ -e ${CONFIG} ]]; then
        # import variables
        . ${CONFIG}
        echo 'ok'
        setup
        cmd $1
      else
        echo
        echo "${NAME}: no one config file in ${CONFIG_PATH}..."
        exit 1  
      fi
    done
  fi
}

if [ $# -eq 0 ]
then
  cmd
else
  main ${ARGS}
fi