init.d nodejs app script

init.d_node-app

#!/bin/sh

USER="nherment"
NODE_ENV="production"
PORT="5000"
APP_DIR="/opt/node-app/latest"
NODE_APP="server.js"
KWARGS=""
APP_NAME="node-app"
PID_DIR="/var/run"
PID_FILE="$PID_DIR/$APP_NAME.pid"
NODE_EXEC="node"

###############

# REDHAT chkconfig header

# chkconfig: - 58 74
# description: this is the script for starting a node app on boot.
### BEGIN INIT INFO
# Provides: node
# Required-Start:    $network $remote_fs $local_fs
# Required-Stop:     $network $remote_fs $local_fs
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: start and stop node
# Description: Node process for app
### END INIT INFO

###############

USAGE="Usage: $0 {start|stop|restart|status}"

pid_file_exists() {
    [ -f "$PID_FILE" ]
}

get_pid() {
    echo "$(cat "$PID_FILE")"
}

is_running() {
    PID=$(get_pid)
    ! [ -z "$(ps aux | awk '{print $2}' | grep "^$PID$")" ]
}

start_it() {
    mkdir -p "$PID_DIR"
    chown $USER:$USER "$PID_DIR"

    echo "Starting $APP_NAME ..."
    su -l $USER -c ". \$HOME/.nvm/nvm.sh && cd $APP_DIR && PORT=$PORT NODE_ENV=$NODE_ENV $NODE_EXEC $APP_DIR/$NODE_APP > \$HOME/logs 2>&1 & echo \$! > $PID_FILE"
    echo "$APP_NAME started with pid $(get_pid)"
}

stop_process() {
    PID=$(get_pid)
    echo "Killing process $PID"
    pkill -P $PID
}

remove_pid_file() {
    echo "Removing pid file"
    rm -f "$PID_FILE"
}

start_app() {
    if pid_file_exists
    then
        if is_running
        then
            PID=$(get_pid)
            echo "$APP_NAME already running with pid $PID"
            exit 1
        else
            echo "$APP_NAME stopped, but pid file exists"
            echo "Forcing start anyways"
            remove_pid_file
            start_it
        fi
    else
        start_it
    fi
}

stop_app() {
    if pid_file_exists
    then
        if is_running
        then
            echo "Stopping $APP_NAME ..."
            stop_process
            remove_pid_file
            echo "$APP_NAME stopped"
        else
            echo "$APP_NAME already stopped, but pid file exists"
            echo "Forcing stop anyways ..."
            remove_pid_file
            echo "$APP_NAME stopped"
        fi
    else
        echo "$APP_NAME already stopped, pid file does not exist"
        exit 1
    fi
}

status_app() {
    if pid_file_exists
    then
        if is_running
        then
            PID=$(get_pid)
            echo "$APP_NAME running with pid $PID"
        else
            echo "$APP_NAME stopped, but pid file exists"
        fi
    else
        echo "$APP_NAME stopped"
    fi
}

case "$2" in

    "")
    ;;

    *)
        echo $USAGE
        exit 1
    ;;
esac

case "$1" in
    start)
        start_app
    ;;

    stop)
        stop_app
    ;;

    restart)
        stop_app
        start_app
    ;;

    status)
        status_app
    ;;

    *)
        echo $USAGE
        exit 1
    ;;
esac