#!/usr/bin/env python
#
# Plugin to monitor used size of a tenant in glance
#
# To monitor the used size of a tenant in glance do:
# E.g.
#    ln -s /usr/share/munin/plugins/glance_size_ /etc/munin/plugins/glance_size_<tenant_uuid>
#
# Needs following minimal configuration in plugin-conf.d/glance:
#   [glance_*]
#   user glance
#
# Magic markers
#%# capabilities=autoconf
#%# family=auto


import sys
import os

try: 
    from sqlalchemy.orm import exc, joinedload
    
    from glance.common.cfg import CommonConfigOpts
    from glance.registry.db import models
    from glance.registry.db.api import get_session, configure_db
except ImportError:
    successful_import = False
else:
    successful_import = True

def load_conf():
    CONF = CommonConfigOpts(project="glance", prog="glance-registry")
    CONF()
    
    # Hide missing logger warning message
    sys.stderr = open(os.devnull, 'w')
    configure_db(CONF)
    sys.stderr = sys.__stderr__

possible_status = [ 'queued', 'saving', 'active', 'killed', 'deleted', 'pending_delete' ]

def print_config():
    print 'graph_title Glance images status'
    print 'graph_vlabel images'
    print 'graph_args --lower-limit 0'
    print 'graph_category glance'
    print 'graph_scale no'
    print 'graph_info This graph show number of images by status'

    for status in possible_status:
        print '%s.label %s' % (status, status)
        print '%s.draw LINE2' % status
        print '%s.info %s image(s)' % (status, status)

def request(**kwargs):

    session = get_session()
    try:
        query = session.query(models.Image).\
                        options(joinedload(models.Image.properties)).\
                        options(joinedload(models.Image.members))
        if kwargs:
           query = query.filter_by(**kwargs)

        images = query.all()

    except exc.NoResultFound:
        return []
    return images

def print_values():
    images = request()

    n_image_by_status = {}
    for image in images:
        n_image_by_status[image["status"]] = n_image_by_status.get(image["status"], 0) + 1

    for status in possible_status: 
        print '%s.value %s' % (status, n_image_by_status.get(status, 0))

if __name__ == '__main__':
    argv = sys.argv[:]

    if len(argv) > 1:
        if argv[1] == 'config':
            print_config()
        elif argv[1] == 'autoconf':
            if not successful_import:  
                print 'no (failed import glance and/or sqlachemy module)'
                sys.exit(0)
            try:
                load_conf()
                get_session()
            except:
                print 'no (failed to connect glance backend, check user)'
                sys.exit(0)
            print 'yes'

    elif successful_import:
        load_conf()
        print_values()