#!/bin/sh -e
# ============================================
#  celeryd - Starts the Celery worker daemon.
# ============================================
#
# :Usage: /etc/init.d/celeryd {start|stop|force-reload|restart|try-restart|status}
#
# :Configuration file: /etc/default/celeryd
#
# To configure celeryd you probably need to tell it where to chdir.
#
# EXAMPLE CONFIGURATION
# =====================
#
# this is an example configuration for a Python project:
#
# /etc/default/celeryd:
#
#   # List of nodes to start
#   CELERYD_NODES="worker1 worker2 worker3"k
#   # ... can also be a number of workers
#   CELERYD_NODES=3
#
#   # Where to chdir at start.
#   CELERYD_CHDIR="/opt/Myproject/"
#
#   # Extra arguments to celeryd
#   CELERYD_OPTS="--time-limit 300"
#
#   # Name of the celery config module.#
#   CELERY_CONFIG_MODULE="celeryconfig"
#
# EXAMPLE DJANGO CONFIGURATION
# ============================
#
#   # Where the Django project is.
#   CELERYD_CHDIR="/opt/Project/"
#
#   # Name of the projects settings module.
#   DJANGO_SETTINGS_MODULE="settings"
#
#   # Path to celeryd
#   CELERYD="/opt/Project/manage.py celeryd"
#
# AVAILABLE OPTIONS
# =================
#
#   * CELERYD_NODES
#
#       A space separated list of nodes, or a number describing the number of
#       nodes, to start
#
#   * CELERYD_OPTS
#       Additional arguments to celeryd-multi, see ``celeryd-multi --help``
#       and ``celeryd --help`` for help.
#
#   * CELERYD_CHDIR
#       Path to chdir at start. Default is to stay in the current directory.
#
#   * CELERYD_PIDFILE
#       Full path to the pidfile. Default is /var/run/celeryd.pid.
#
#   * CELERYD_LOGFILE
#       Full path to the celeryd logfile. Default is /var/log/celeryd.log
#
#   * CELERYD_LOG_LEVEL
#       Log level to use for celeryd. Default is INFO.
#
#   * CELERYD
#       Path to the celeryd program. Default is ``celeryd``.
#       You can point this to an virtualenv, or even use manage.py for django.
#
#   * CELERYD_USER
#       User to run celeryd as. Default is current user.
#
#   * CELERYD_GROUP
#       Group to run celeryd as. Default is current user.

# VARIABLE EXPANSION
# ==================
#
# The following abbreviations will be expanded
#
# * %n -> node name
# * %h -> host name


### BEGIN INIT INFO
# Provides:          celeryd
# Required-Start:    $network $local_fs $remote_fs
# Required-Stop:     $network $local_fs $remote_fs
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: celery task worker daemon
### END INIT INFO

# OS X Debug replacements to lsb-functions.
log_action_msg () {
    echo $*
}
log_daemon_msg () {
    echo $*
}
log_end_msg () {
    if [ $1 -eq 0 ]; then
        echo "ok"
    else
        echo "failed!"
    fi
}


set -e

CELERYD_PID_FILE="celeryd@%n.pid"
CELERYD_LOG_FILE="celeryd@%n.log"
CELERYD_LOG_LEVEL="INFO"
DEFAULT_CELERYD="celeryd"

# /etc/init.d/ssh: start and stop the celery task worker daemon.

if test -f /etc/default/celeryd; then
    . /etc/default/celeryd
fi

CELERYD_MULTI=${CELERYD_MULTI:-"celeryd-multi"}
CELERYD=${CELERYD:-$DEFAULT_CELERYD}
CELERYD_NODES=${CELERYD_NODES:-"celery"}

export CELERY_LOADER

CELERYD_OPTS="$CELERYD_OPTS --logfile=$CELERYD_LOG_FILE \
                            --loglevel=$CELERYD_LOG_LEVEL"

if [ -n "$2" ]; then
    CELERYD_OPTS="$CELERYD_OPTS $2"
fi

# Extra start-stop-daemon options, like user/group.
if [ -n "$CELERYD_USER" ]; then
    DAEMON_OPTS="$DAEMON_OPTS --uid=$CELERYD_USER"
fi
if [ -n "$CELERYD_GROUP" ]; then
    DAEMON_OPTS="$DAEMON_OPTS --gid=$CELERYD_GROUP"
fi

if [ -n "$CELERYD_CHDIR" ]; then
    DAEMON_OPTS="$DAEMON_OPTS --chdir=$CELERYD_CHDIR"
fi


# Are we running from init?
run_by_init() {
    ([ "$previous" ] && [ "$runlevel" ]) || [ "$runlevel" = S ]
}


check_dev_null() {
    if [ ! -c /dev/null ]; then
    if [ "$1" = log_end_msg ]; then
        log_end_msg 1 || true
    fi
    if ! run_by_init; then
        log_action_msg "/dev/null is not a character device!"
    fi
    exit 1
    fi
}


export PATH="${PATH:+$PATH:}/usr/sbin:/sbin"


stop_worker () {
    cmd="celeryd-multi stop $CELERYD_NODES --pidfile=$CELERYD_PID_FILE"
    if $cmd; then
        log_end_msg 0
    else
        log_end_msg 1
    fi
}

start_worker () {
    cmd="celeryd-multi detach $CELERYD_NODES $DAEMON_OPTS \
                              --pidfile=$CELERYD_PID_FILE \
                              --cmd="$CELERYD" \
                              $CELERYD_OPTS"
    if $cmd; then
        log_end_msg 0
    else
        log_end_msg 1
    fi
}



case "$1" in
  start)
    check_dev_null
    log_daemon_msg "Starting celery worker nodes" "celeryd-multi"
    start_worker
    ;;
  stop)
    log_daemon_msg "Stopping celery worker nodes" "celeryd-multi"
    stop_worker
    ;;

  reload|force-reload)
    echo "Use start+stop"
    ;;

  restart)
    log_daemon_msg "Restarting celery worker nodes" "celeryd-multi"
    stop_worker
    check_dev_null log_end_msg
    start_worker
    ;;

  try-restart)
    log_daemon_msg "Restarting celery worker nodes" "celeryd-multi"
    set +e
    stop_worker
    RET="$?"
    set -e
    case $RET in
        0)
        # old daemon stopped
        check_dev_null log_end_msg
        start_worker
        ;;
        1)
        # daemon not running
        log_progress_msg "(not running)"
        log_end_msg 0
        ;;
        *)
        # failed to stop
        log_progress_msg "(failed to stop)"
        log_end_msg 1
        ;;
    esac
    ;;

  *)
    log_action_msg "Usage: /etc/init.d/celeryd {start|stop|force-reload|restart|try-restart|status}"
    exit 1
esac

exit 0
