#!/usr/bin/env python -t
# encoding: utf-8
# origin:   http://overt.org/2010/02/15/off-site-backup-for-010gb-using-dirvish-and-amazon-ec2-and-ebs/
"""
run_offsite_backups.py
 
Wake up the EC2 backup server, run dirvish backup, then shut it down
 
Created by Bryan Klingner (code.b@overt.org) on 2010-02-02.
Feel free to use this code yourself. Maybe email me if you do :)
"""
 
import sys
import os
import boto
import time
import subprocess
 
BACKUP_INSTANCE_ID = 'YOUR_INSTANCE_ID'
 
def main():
 
    conn = boto.connect_ec2()
 
    # get the backup instance object
    instance = conn.get_all_instances(instance_ids=(BACKUP_INSTANCE_ID,))[0].instances[0]
 
    # if the instance is stopped, start it up
    if instance.state != 'running':
        conn.start_instances(instance_ids=(BACKUP_INSTANCE_ID,))
        waited = 0
        while instance.state != 'running':
            instance.update()
            sys.stdout.write("\rInstance starting up (%d sec)..." % (waited))
            sys.stdout.flush()
            time.sleep(1)
            waited += 1
 
    print "\n"
    print "Backup instance running:"
    print "    ID:       ", instance.id
    print "    State:    ", instance.state
    print "    DNS name: ", instance.dns_name
 
    # chill for a few seconds so the SSH server is listening
    time.sleep(10)
 
    print ""
    print "Initiating backup..."
    retcode = ssh_cmd('dirvish-expire; dirvish-runall', instance.dns_name, user='username')
    print ""
 
    # backup is done; shut down the instance
    conn.stop_instances(instance_ids=(BACKUP_INSTANCE_ID,))
    waited = 0
    while instance.state != 'stopped':
        instance.update()
        sys.stdout.write("\rInstance shutting down (%d sec)..." % (waited))
        sys.stdout.flush()
        time.sleep(1)
        waited += 1
    print ""
 
def ssh_cmd(cmd, host, user='root'):
    """ Run a shell command on a remote server via ssh """
 
    ssh_cmd = 'ssh -o ConnectTimeout=5 -o StrictHostKeyChecking=no ' + user + '@' + host + " '%s'" % (cmd)
    print "Running SSH command: %s" % ssh_cmd
    returncode = subprocess.call(ssh_cmd, shell=True)
 
    #logging.debug( output, returncode )
    return returncode
 
if __name__ == '__main__':
    main()