Refactored implementation to make use of caching and to

limit the number of connections to external cobbler server for performance.
Added use of cobbler.ini file to configure settings.

Tested against Cobbler 2.4.0
This commit is contained in:
Peter Gehres 2013-09-23 14:08:16 -07:00 committed by Michael DeHaan
parent a3e3334547
commit 084dc38fbe

View file

@ -28,6 +28,11 @@ that those correspond to addresses.
See http://ansible.github.com/api.html for more info
Tested with Cobbler 2.0.11.
Changelog:
- 2013-09-01 pgehres: Refactored implementation to make use of caching and to
limit the number of connections to external cobbler server for performance.
Added use of cobbler.ini file to configure settings. Tested with Cobbler 2.4.0
"""
# (c) 2012, Michael DeHaan <michael.dehaan@gmail.com>
@ -50,86 +55,210 @@ Tested with Cobbler 2.0.11.
######################################################################
import sys
import argparse
import ConfigParser
import os
import re
from time import time
import xmlrpclib
import shlex
try:
import json
except:
except ImportError:
import simplejson as json
# NOTE -- this file assumes Ansible is being accessed FROM the cobbler
# server, so it does not attempt to login with a username and password.
# this will be addressed in a future version of this script.
conn = xmlrpclib.Server("http://127.0.0.1/cobbler_api", allow_none=True)
###################################################
# executed with no parameters, return the list of
# all groups and hosts
class CobblerInventory(object):
if len(sys.argv) == 2 and (sys.argv[1] == '--list'):
def __init__(self):
""" Main execution path """
self.conn = None
systems = conn.get_item_names('system')
groups = { 'ungrouped' : [] }
self.inventory = dict() # A list of groups and the hosts in that group
self.cache = dict() # Details about hosts in the inventory
for system in systems:
# Read settings and parse CLI arguments
self.read_settings()
self.parse_cli_args()
data = conn.get_blended_data(None, system)
# Cache
if self.args.refresh_cache:
self.update_cache()
elif not self.is_cache_valid():
self.update_cache()
else:
self.load_inventory_from_cache()
self.load_cache_from_cache()
dns_name = None
interfaces = data['interfaces']
for (iname, ivalue) in interfaces.iteritems():
this_dns_name = ivalue.get('dns_name', None)
if this_dns_name is not None:
dns_name = this_dns_name
data_to_print = ""
if dns_name is None:
continue
# Data to print
if self.args.host:
data_to_print = self.get_host_info()
classes = data['mgmt_classes']
for cls in classes:
if cls not in groups:
groups[cls] = []
# hostname is not really what we want to insert, really insert the
# first DNS name but no further DNS names
groups[cls].append(dns_name)
elif self.args.list:
# Display list of instances for inventory
data_to_print = self.json_format_dict(self.inventory, True)
# handle hosts without mgmt_classes
if not classes:
groups['ungrouped'].append(dns_name)
else: # default action with no options
data_to_print = self.json_format_dict(self.inventory, True)
print json.dumps(groups)
sys.exit(0)
print data_to_print
#####################################################
# executed with a hostname as a parameter, return the
# variables for that host
def _connect(self):
if not self.conn:
self.conn = xmlrpclib.Server(self.cobbler_host, allow_none=True)
elif len(sys.argv) == 3 and (sys.argv[1] == '--host'):
def is_cache_valid(self):
""" Determines if the cache files have expired, or if it is still valid """
# look up the system record for the given DNS name
result = conn.find_system_by_dns_name(sys.argv[2])
system = result.get('name', None)
data = {}
if system is None:
print json.dumps({})
sys.exit(1)
data = conn.get_system_for_koan(system)
if os.path.isfile(self.cache_path_cache):
mod_time = os.path.getmtime(self.cache_path_cache)
current_time = time()
if (mod_time + self.cache_max_age) > current_time:
if os.path.isfile(self.cache_path_inventory):
return True
# return the ksmeta data for that system
metadata = data['ks_meta']
tokens = shlex.split(metadata)
results = {}
for t in tokens:
if t.find("=") != -1:
(k,v) = t.split("=",1)
results[k]=v
print json.dumps(results)
sys.exit(0)
return False
else:
def read_settings(self):
""" Reads the settings from the cobbler.ini file """
print "usage: --list ..OR.. --host <hostname>"
sys.exit(1)
config = ConfigParser.SafeConfigParser()
config.read(os.path.dirname(os.path.realpath(__file__)) + '/cobbler.ini')
self.cobbler_host = config.get('cobbler', 'host')
# Cache related
cache_path = config.get('cobbler', 'cache_path')
self.cache_path_cache = cache_path + "/ansible-cobbler.cache"
self.cache_path_inventory = cache_path + "/ansible-cobbler.index"
self.cache_max_age = config.getint('cobbler', 'cache_max_age')
def parse_cli_args(self):
""" Command line argument processing """
parser = argparse.ArgumentParser(description='Produce an Ansible Inventory file based on Cobbler')
parser.add_argument('--list', action='store_true', default=True, help='List instances (default: True)')
parser.add_argument('--host', action='store', help='Get all the variables about a specific instance')
parser.add_argument('--refresh-cache', action='store_true', default=False,
help='Force refresh of cache by making API requests to cobbler (default: False - use cache files)')
self.args = parser.parse_args()
def update_cache(self):
""" Make calls to cobbler and save the output in a cache """
self._connect()
self.groups = dict()
self.hosts = dict()
data = self.conn.get_systems()
for host in data:
# Get the FQDN for the host and add it to the right groups
dns_name = None
ksmeta = None
interfaces = host['interfaces']
for (iname, ivalue) in interfaces.iteritems():
if ivalue['management']:
this_dns_name = ivalue.get('dns_name', None)
if this_dns_name is not None and this_dns_name is not "":
dns_name = this_dns_name
if dns_name is None:
continue
status = host['status']
profile = host['profile']
classes = host['mgmt_classes']
if status not in self.inventory:
self.inventory[status] = []
self.inventory[status].append(dns_name)
if profile not in self.inventory:
self.inventory[profile] = []
self.inventory[profile].append(dns_name)
for cls in classes:
if cls not in self.inventory:
self.inventory[cls] = []
self.inventory[cls].append(dns_name)
# Since we already have all of the data for the host, update the host details as well
# The old way was ksmeta only -- provide backwards compatibility
self.cache[dns_name] = dict()
if "ks_meta" in host:
for key, value in host["ks_meta"].iteritems():
self.cache[dns_name][key] = value
self.write_to_cache(self.cache, self.cache_path_cache)
self.write_to_cache(self.inventory, self.cache_path_inventory)
def get_host_info(self):
""" Get variables about a specific host """
if not self.cache or len(self.cache) == 0:
# Need to load index from cache
self.load_cache_from_cache()
if not self.args.host in self.cache:
# try updating the cache
self.update_cache()
if not self.args.host in self.cache:
# host might not exist anymore
return self.json_format_dict({}, True)
return self.json_format_dict(self.cache[self.args.host], True)
def push(self, my_dict, key, element):
""" Pushed an element onto an array that may not have been defined in the dict """
if key in my_dict:
my_dict[key].append(element)
else:
my_dict[key] = [element]
def load_inventory_from_cache(self):
""" Reads the index from the cache file sets self.index """
cache = open(self.cache_path_inventory, 'r')
json_inventory = cache.read()
self.inventory = json.loads(json_inventory)
def load_cache_from_cache(self):
""" Reads the cache from the cache file sets self.cache """
cache = open(self.cache_path_cache, 'r')
json_cache = cache.read()
self.cache = json.loads(json_cache)
def write_to_cache(self, data, filename):
""" Writes data in JSON format to a file """
json_data = self.json_format_dict(data, True)
cache = open(filename, 'w')
cache.write(json_data)
cache.close()
def to_safe(self, word):
""" Converts 'bad' characters in a string to underscores so they can be used as Ansible groups """
return re.sub("[^A-Za-z0-9\-]", "_", word)
def json_format_dict(self, data, pretty=False):
""" Converts a dict to a JSON object and dumps it as a formatted string """
if pretty:
return json.dumps(data, sort_keys=True, indent=2)
else:
return json.dumps(data)
CobblerInventory()