#!/usr/bin/env python ''' EC2 external inventory script ================================= Generates inventory that Ansible can understand by making API request to AWS EC2 using the Boto library. NOTE: This script assumes Ansible is being executed where the environment variables needed for Boto have already been set: export AWS_ACCESS_KEY_ID='AK123' export AWS_SECRET_ACCESS_KEY='abc123' This script also assumes there is an ec2.ini file alongside it. To specify a different path to ec2.ini, define the EC2_INI_PATH environment variable: export EC2_INI_PATH=/path/to/my_ec2.ini If you're using eucalyptus you need to set the above variables and you need to define: export EC2_URL=http://hostname_of_your_cc:port/services/Eucalyptus For more details, see: http://docs.pythonboto.org/en/latest/boto_config_tut.html When run against a specific host, this script returns the following variables: - ec2_ami_launch_index - ec2_architecture - ec2_association - ec2_attachTime - ec2_attachment - ec2_attachmentId - ec2_client_token - ec2_deleteOnTermination - ec2_description - ec2_deviceIndex - ec2_dns_name - ec2_eventsSet - ec2_group_name - ec2_hypervisor - ec2_id - ec2_image_id - ec2_instanceState - ec2_instance_type - ec2_ipOwnerId - ec2_ip_address - ec2_item - ec2_kernel - ec2_key_name - ec2_launch_time - ec2_monitored - ec2_monitoring - ec2_networkInterfaceId - ec2_ownerId - ec2_persistent - ec2_placement - ec2_platform - ec2_previous_state - ec2_private_dns_name - ec2_private_ip_address - ec2_publicIp - ec2_public_dns_name - ec2_ramdisk - ec2_reason - ec2_region - ec2_requester_id - ec2_root_device_name - ec2_root_device_type - ec2_security_group_ids - ec2_security_group_names - ec2_shutdown_state - ec2_sourceDestCheck - ec2_spot_instance_request_id - ec2_state - ec2_state_code - ec2_state_reason - ec2_status - ec2_subnet_id - ec2_tenancy - ec2_virtualization_type - ec2_vpc_id These variables are pulled out of a boto.ec2.instance object. There is a lack of consistency with variable spellings (camelCase and underscores) since this just loops through all variables the object exposes. It is preferred to use the ones with underscores when multiple exist. In addition, if an instance has AWS Tags associated with it, each tag is a new variable named: - ec2_tag_[Key] = [Value] Security groups are comma-separated in 'ec2_security_group_ids' and 'ec2_security_group_names'. ''' # (c) 2012, Peter Sankauskas # # This file is part of Ansible, # # Ansible is free software: you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation, either version 3 of the License, or # (at your option) any later version. # # Ansible is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with Ansible. If not, see . ###################################################################### import sys import os import argparse import re from time import time import boto from boto import ec2 from boto import rds from boto import route53 import ConfigParser try: import json except ImportError: import simplejson as json class Ec2Inventory(object): def __init__(self): ''' Main execution path ''' # Inventory grouped by instance IDs, tags, security groups, regions, # and availability zones self.inventory = {} # Index of hostname (address) to instance ID self.index = {} # Read settings and parse CLI arguments self.read_settings() self.parse_cli_args() # Cache if self.args.refresh_cache: self.do_api_calls_update_cache() elif not self.is_cache_valid(): self.do_api_calls_update_cache() # Data to print if self.args.host: data_to_print = self.get_host_info() elif self.args.list: # Display list of instances for inventory if len(self.inventory) == 0: data_to_print = self.get_inventory_from_cache() else: data_to_print = self.json_format_dict(self.inventory, True) print data_to_print def is_cache_valid(self): ''' Determines if the cache files have expired, or if it is still valid ''' 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_index): return True return False def read_settings(self): ''' Reads the settings from the ec2.ini file ''' config = ConfigParser.SafeConfigParser() ec2_default_ini_path = os.path.join(os.path.dirname(os.path.realpath(__file__)), 'ec2.ini') ec2_ini_path = os.environ.get('EC2_INI_PATH', ec2_default_ini_path) config.read(ec2_ini_path) # is eucalyptus? self.eucalyptus_host = None self.eucalyptus = False if config.has_option('ec2', 'eucalyptus'): self.eucalyptus = config.getboolean('ec2', 'eucalyptus') if self.eucalyptus and config.has_option('ec2', 'eucalyptus_host'): self.eucalyptus_host = config.get('ec2', 'eucalyptus_host') # Regions self.regions = [] configRegions = config.get('ec2', 'regions') configRegions_exclude = config.get('ec2', 'regions_exclude') if (configRegions == 'all'): if self.eucalyptus_host: self.regions.append(boto.connect_euca(host=self.eucalyptus_host).region.name) else: for regionInfo in ec2.regions(): if regionInfo.name not in configRegions_exclude: self.regions.append(regionInfo.name) else: self.regions = configRegions.split(",") # Destination addresses self.destination_variable = config.get('ec2', 'destination_variable') self.vpc_destination_variable = config.get('ec2', 'vpc_destination_variable') # Route53 self.route53_enabled = config.getboolean('ec2', 'route53') self.route53_excluded_zones = [] if config.has_option('ec2', 'route53_excluded_zones'): self.route53_excluded_zones.extend( config.get('ec2', 'route53_excluded_zones', '').split(',')) # Cache related cache_path = config.get('ec2', 'cache_path') self.cache_path_cache = cache_path + "/ansible-ec2.cache" self.cache_path_index = cache_path + "/ansible-ec2.index" self.cache_max_age = config.getint('ec2', 'cache_max_age') def parse_cli_args(self): ''' Command line argument processing ''' parser = argparse.ArgumentParser(description='Produce an Ansible Inventory file based on EC2') 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 EC2 (default: False - use cache files)') self.args = parser.parse_args() def do_api_calls_update_cache(self): ''' Do API calls to each region, and save data in cache files ''' if self.route53_enabled: self.get_route53_records() for region in self.regions: self.get_instances_by_region(region) self.get_rds_instances_by_region(region) self.write_to_cache(self.inventory, self.cache_path_cache) self.write_to_cache(self.index, self.cache_path_index) def get_instances_by_region(self, region): ''' Makes an AWS EC2 API call to the list of instances in a particular region ''' try: if self.eucalyptus: conn = boto.connect_euca(host=self.eucalyptus_host) conn.APIVersion = '2010-08-31' else: conn = ec2.connect_to_region(region) # connect_to_region will fail "silently" by returning None if the region name is wrong or not supported if conn is None: print("region name: %s likely not supported, or AWS is down. connection to region failed." % region) sys.exit(1) reservations = conn.get_all_instances() for reservation in reservations: for instance in reservation.instances: self.add_instance(instance, region) except boto.exception.BotoServerError as e: if not self.eucalyptus: print "Looks like AWS is down again:" print e sys.exit(1) def get_rds_instances_by_region(self, region): ''' Makes an AWS API call to the list of RDS instances in a particular region ''' try: conn = rds.connect_to_region(region) if conn: instances = conn.get_all_dbinstances() for instance in instances: self.add_rds_instance(instance, region) except boto.exception.BotoServerError as e: print "Looks like AWS RDS is down: " print e sys.exit(1) def get_instance(self, region, instance_id): ''' Gets details about a specific instance ''' if self.eucalyptus: conn = boto.connect_euca(self.eucalyptus_host) conn.APIVersion = '2010-08-31' else: conn = ec2.connect_to_region(region) # connect_to_region will fail "silently" by returning None if the region name is wrong or not supported if conn is None: print("region name: %s likely not supported, or AWS is down. connection to region failed." % region) sys.exit(1) reservations = conn.get_all_instances([instance_id]) for reservation in reservations: for instance in reservation.instances: return instance def add_instance(self, instance, region): ''' Adds an instance to the inventory and index, as long as it is addressable ''' # Only want running instances if instance.state != 'running': return # Select the best destination address if instance.subnet_id: dest = getattr(instance, self.vpc_destination_variable) else: dest = getattr(instance, self.destination_variable) if not dest: # Skip instances we cannot address (e.g. private VPC subnet) return # Add to index self.index[dest] = [region, instance.id] # Inventory: Group by instance ID (always a group of 1) self.inventory[instance.id] = [dest] # Inventory: Group by region self.push(self.inventory, region, dest) # Inventory: Group by availability zone self.push(self.inventory, instance.placement, dest) # Inventory: Group by instance type self.push(self.inventory, self.to_safe('type_' + instance.instance_type), dest) # Inventory: Group by key pair if instance.key_name: self.push(self.inventory, self.to_safe('key_' + instance.key_name), dest) # Inventory: Group by security group try: for group in instance.groups: key = self.to_safe("security_group_" + group.name) self.push(self.inventory, key, dest) except AttributeError: print 'Package boto seems a bit older.' print 'Please upgrade boto >= 2.3.0.' sys.exit(1) # Inventory: Group by tag keys for k, v in instance.tags.iteritems(): key = self.to_safe("tag_" + k + "=" + v) self.push(self.inventory, key, dest) # Inventory: Group by Route53 domain names if enabled if self.route53_enabled: route53_names = self.get_instance_route53_names(instance) for name in route53_names: self.push(self.inventory, name, dest) # Global Tag: tag all EC2 instances self.push(self.inventory, 'ec2', dest) def add_rds_instance(self, instance, region): ''' Adds an RDS instance to the inventory and index, as long as it is addressable ''' # Only want available instances if instance.status != 'available': return # Select the best destination address #if instance.subnet_id: #dest = getattr(instance, self.vpc_destination_variable) #else: #dest = getattr(instance, self.destination_variable) dest = instance.endpoint[0] if not dest: # Skip instances we cannot address (e.g. private VPC subnet) return # Add to index self.index[dest] = [region, instance.id] # Inventory: Group by instance ID (always a group of 1) self.inventory[instance.id] = [dest] # Inventory: Group by region self.push(self.inventory, region, dest) # Inventory: Group by availability zone self.push(self.inventory, instance.availability_zone, dest) # Inventory: Group by instance type self.push(self.inventory, self.to_safe('type_' + instance.instance_class), dest) # Inventory: Group by security group try: if instance.security_group: key = self.to_safe("security_group_" + instance.security_group.name) self.push(self.inventory, key, dest) except AttributeError: print 'Package boto seems a bit older.' print 'Please upgrade boto >= 2.3.0.' sys.exit(1) # Inventory: Group by engine self.push(self.inventory, self.to_safe("rds_" + instance.engine), dest) # Inventory: Group by parameter group self.push(self.inventory, self.to_safe("rds_parameter_group_" + instance.parameter_group.name), dest) # Global Tag: all RDS instances self.push(self.inventory, 'rds', dest) def get_route53_records(self): ''' Get and store the map of resource records to domain names that point to them. ''' r53_conn = route53.Route53Connection() all_zones = r53_conn.get_zones() route53_zones = [ zone for zone in all_zones if zone.name[:-1] not in self.route53_excluded_zones ] self.route53_records = {} for zone in route53_zones: rrsets = r53_conn.get_all_rrsets(zone.id) for record_set in rrsets: record_name = record_set.name if record_name.endswith('.'): record_name = record_name[:-1] for resource in record_set.resource_records: self.route53_records.setdefault(resource, set()) self.route53_records[resource].add(record_name) def get_instance_route53_names(self, instance): ''' Check if an instance is referenced in the records we have from Route53. If it is, return the list of domain names pointing to said instance. If nothing points to it, return an empty list. ''' instance_attributes = [ 'public_dns_name', 'private_dns_name', 'ip_address', 'private_ip_address' ] name_list = set() for attrib in instance_attributes: try: value = getattr(instance, attrib) except AttributeError: continue if value in self.route53_records: name_list.update(self.route53_records[value]) return list(name_list) def get_host_info(self): ''' Get variables about a specific host ''' if len(self.index) == 0: # Need to load index from cache self.load_index_from_cache() if not self.args.host in self.index: # try updating the cache self.do_api_calls_update_cache() if not self.args.host in self.index: # host migh not exist anymore return self.json_format_dict({}, True) (region, instance_id) = self.index[self.args.host] instance = self.get_instance(region, instance_id) instance_vars = {} for key in vars(instance): value = getattr(instance, key) key = self.to_safe('ec2_' + key) # Handle complex types if type(value) in [int, bool]: instance_vars[key] = value elif type(value) in [str, unicode]: instance_vars[key] = value.strip() elif type(value) == type(None): instance_vars[key] = '' elif key == 'ec2_region': instance_vars[key] = value.name elif key == 'ec2_tags': for k, v in value.iteritems(): key = self.to_safe('ec2_tag_' + k) instance_vars[key] = v elif key == 'ec2_groups': group_ids = [] group_names = [] for group in value: group_ids.append(group.id) group_names.append(group.name) instance_vars["ec2_security_group_ids"] = ','.join(group_ids) instance_vars["ec2_security_group_names"] = ','.join(group_names) else: pass # TODO Product codes if someone finds them useful #print key #print type(value) #print value return self.json_format_dict(instance_vars, 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 get_inventory_from_cache(self): ''' Reads the inventory from the cache file and returns it as a JSON object ''' cache = open(self.cache_path_cache, 'r') json_inventory = cache.read() return json_inventory def load_index_from_cache(self): ''' Reads the index from the cache file sets self.index ''' cache = open(self.cache_path_index, 'r') json_index = cache.read() self.index = json.loads(json_index) 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) # Run the script Ec2Inventory()