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github-octodns/octodns/provider/azuredns.py
2021-05-10 20:49:28 -07:00

560 lines
20 KiB
Python

#
#
#
from __future__ import absolute_import, division, print_function, \
unicode_literals
from azure.identity import ClientSecretCredential
from azure.mgmt.dns import DnsManagementClient
from azure.mgmt.dns.models import ARecord, AaaaRecord, CaaRecord, \
CnameRecord, MxRecord, SrvRecord, NsRecord, PtrRecord, TxtRecord, Zone
import logging
from functools import reduce
from ..record import Record
from .base import BaseProvider
def escape_semicolon(s):
assert s
return s.replace(';', '\\;')
def unescape_semicolon(s):
assert s
return s.replace('\\;', ';')
def azure_chunked_value(val):
CHUNK_SIZE = 255
val_replace = val.replace('"', '\\"')
value = unescape_semicolon(val_replace)
if len(val) > CHUNK_SIZE:
vs = [value[i:i + CHUNK_SIZE]
for i in range(0, len(value), CHUNK_SIZE)]
else:
vs = value
return vs
def azure_chunked_values(s):
values = []
for v in s:
values.append(azure_chunked_value(v))
return values
class _AzureRecord(object):
'''Wrapper for OctoDNS record for AzureProvider to make dns_client calls.
azuredns.py:
class: octodns.provider.azuredns._AzureRecord
An _AzureRecord is easily accessible to Azure DNS Management library
functions and is used to wrap all relevant data to create a record in
Azure.
'''
TYPE_MAP = {
'A': ARecord,
'AAAA': AaaaRecord,
'CAA': CaaRecord,
'CNAME': CnameRecord,
'MX': MxRecord,
'SRV': SrvRecord,
'NS': NsRecord,
'PTR': PtrRecord,
'TXT': TxtRecord
}
def __init__(self, resource_group, record, delete=False):
'''Constructor for _AzureRecord.
Notes on Azure records: An Azure record set has the form
RecordSet(name=<...>, type=<...>, a_records=[...],
aaaa_records=[...], ...)
When constructing an azure record as done in self._apply_Create,
the argument parameters for an A record would be
parameters={'ttl': <int>, 'a_records': [ARecord(<str ip>),]}.
As another example for CNAME record:
parameters={'ttl': <int>, 'cname_record': CnameRecord(<str>)}.
Below, key_name and class_name are the dictionary key and Azure
Record class respectively.
:param resource_group: The name of resource group in Azure
:type resource_group: str
:param record: An OctoDNS record
:type record: ..record.Record
:param delete: If true, omit data parsing; not needed to delete
:type delete: bool
:type return: _AzureRecord
'''
self.log = logging.getLogger('AzureRecord')
self.resource_group = resource_group
self.zone_name = record.zone.name[:len(record.zone.name) - 1]
self.relative_record_set_name = record.name or '@'
self.record_type = record._type
if delete:
return
# Refer to function docstring for key_name and class_name.
key_name = '{}_records'.format(self.record_type).lower()
if record._type == 'CNAME':
key_name = key_name[:len(key_name) - 1]
azure_class = self.TYPE_MAP[self.record_type]
self.params = getattr(self, '_params_for_{}'.format(record._type))
self.params = self.params(record.data, key_name, azure_class)
self.params['ttl'] = record.ttl
def _params_for_A(self, data, key_name, azure_class):
try:
values = data['values']
except KeyError:
values = [data['value']]
return {key_name: [azure_class(ipv4_address=v) for v in values]}
def _params_for_AAAA(self, data, key_name, azure_class):
try:
values = data['values']
except KeyError:
values = [data['value']]
return {key_name: [azure_class(ipv6_address=v) for v in values]}
def _params_for_CAA(self, data, key_name, azure_class):
params = []
if 'values' in data:
for vals in data['values']:
params.append(azure_class(flags=vals['flags'],
tag=vals['tag'],
value=vals['value']))
else: # Else there is a singular data point keyed by 'value'.
params.append(azure_class(flags=data['value']['flags'],
tag=data['value']['tag'],
value=data['value']['value']))
return {key_name: params}
def _params_for_CNAME(self, data, key_name, azure_class):
return {key_name: azure_class(cname=data['value'])}
def _params_for_MX(self, data, key_name, azure_class):
params = []
if 'values' in data:
for vals in data['values']:
params.append(azure_class(preference=vals['preference'],
exchange=vals['exchange']))
else: # Else there is a singular data point keyed by 'value'.
params.append(azure_class(preference=data['value']['preference'],
exchange=data['value']['exchange']))
return {key_name: params}
def _params_for_SRV(self, data, key_name, azure_class):
params = []
if 'values' in data:
for vals in data['values']:
params.append(azure_class(priority=vals['priority'],
weight=vals['weight'],
port=vals['port'],
target=vals['target']))
else: # Else there is a singular data point keyed by 'value'.
params.append(azure_class(priority=data['value']['priority'],
weight=data['value']['weight'],
port=data['value']['port'],
target=data['value']['target']))
return {key_name: params}
def _params_for_NS(self, data, key_name, azure_class):
try:
values = data['values']
except KeyError:
values = [data['value']]
return {key_name: [azure_class(nsdname=v) for v in values]}
def _params_for_PTR(self, data, key_name, azure_class):
try:
values = data['values']
except KeyError:
values = [data['value']]
return {key_name: [azure_class(ptrdname=v) for v in values]}
def _params_for_TXT(self, data, key_name, azure_class):
params = []
try: # API for TxtRecord has list of str, even for singleton
values = [v for v in azure_chunked_values(data['values'])]
except KeyError:
values = [azure_chunked_value(data['value'])]
for v in values:
if isinstance(v, list):
params.append(azure_class(value=v))
else:
params.append(azure_class(value=[v]))
return {key_name: params}
def _equals(self, b):
'''Checks whether two records are equal by comparing all fields.
:param b: Another _AzureRecord object
:type b: _AzureRecord
:type return: bool
'''
def key_dict(d):
return sum([hash('{}:{}'.format(k, v)) for k, v in d.items()])
def parse_dict(params):
vals = []
for char in params:
if char != 'ttl':
list_records = params[char]
try:
for record in list_records:
vals.append(record.__dict__)
except:
vals.append(list_records.__dict__)
vals.sort(key=key_dict)
return vals
return (self.resource_group == b.resource_group) & \
(self.zone_name == b.zone_name) & \
(self.record_type == b.record_type) & \
(self.params['ttl'] == b.params['ttl']) & \
(parse_dict(self.params) == parse_dict(b.params)) & \
(self.relative_record_set_name == b.relative_record_set_name)
def __str__(self):
'''String representation of an _AzureRecord.
:type return: str
'''
string = 'Zone: {}; '.format(self.zone_name)
string += 'Name: {}; '.format(self.relative_record_set_name)
string += 'Type: {}; '.format(self.record_type)
if not hasattr(self, 'params'):
return string
string += 'Ttl: {}; '.format(self.params['ttl'])
for char in self.params:
if char != 'ttl':
try:
for rec in self.params[char]:
string += 'Record: {}; '.format(rec.__dict__)
except:
string += 'Record: {}; '.format(self.params[char].__dict__)
return string
def _check_endswith_dot(string):
return string if string.endswith('.') else string + '.'
def _parse_azure_type(string):
'''Converts string representing an Azure RecordSet type to usual type.
:param string: the Azure type. eg: <Microsoft.Network/dnszones/A>
:type string: str
:type return: str
'''
return string.split('/')[len(string.split('/')) - 1]
def _check_for_alias(azrecord):
if (azrecord.target_resource.id and not azrecord.a_records and not
azrecord.cname_record):
return True
return False
class AzureProvider(BaseProvider):
'''
Azure DNS Provider
azuredns.py:
class: octodns.provider.azuredns.AzureProvider
# Current support of authentication of access to Azure services only
# includes using a Service Principal:
# https://docs.microsoft.com/en-us/azure/azure-resource-manager/
# resource-group-create-service-principal-portal
# The Azure Active Directory Application ID (aka client ID):
client_id:
# Authentication Key Value: (note this should be secret)
key:
# Directory ID (aka tenant ID):
directory_id:
# Subscription ID:
sub_id:
# Resource Group name:
resource_group:
# All are required to authenticate.
Example config file with variables:
"
---
providers:
config:
class: octodns.provider.yaml.YamlProvider
directory: ./config (example path to directory of zone files)
azuredns:
class: octodns.provider.azuredns.AzureProvider
client_id: env/AZURE_APPLICATION_ID
key: env/AZURE_AUTHENTICATION_KEY
directory_id: env/AZURE_DIRECTORY_ID
sub_id: env/AZURE_SUBSCRIPTION_ID
resource_group: 'TestResource1'
zones:
example.com.:
sources:
- config
targets:
- azuredns
"
The first four variables above can be hidden in environment variables
and octoDNS will automatically search for them in the shell. It is
possible to also hard-code into the config file: eg, resource_group.
'''
SUPPORTS_GEO = False
SUPPORTS_DYNAMIC = False
SUPPORTS = set(('A', 'AAAA', 'CAA', 'CNAME', 'MX', 'NS', 'PTR', 'SRV',
'TXT'))
def __init__(self, id, client_id, key, directory_id, sub_id,
resource_group, *args, **kwargs):
self.log = logging.getLogger('AzureProvider[{}]'.format(id))
self.log.debug('__init__: id=%s, client_id=%s, '
'key=***, directory_id:%s', id, client_id, directory_id)
super(AzureProvider, self).__init__(id, *args, **kwargs)
# Store necessary initialization params
self._dns_client_handle = None
self._dns_client_client_id = client_id
self._dns_client_key = key
self._dns_client_directory_id = directory_id
self._dns_client_subscription_id = sub_id
self.__dns_client = None
self._resource_group = resource_group
self._azure_zones = set()
@property
def _dns_client(self):
if self.__dns_client is None:
credential = ClientSecretCredential(
client_id=self._dns_client_client_id,
client_secret=self._dns_client_key,
tenant_id=self._dns_client_directory_id
)
self.__dns_client = DnsManagementClient(
credential=credential,
subscription_id=self._dns_client_subscription_id
)
return self.__dns_client
def _populate_zones(self):
self.log.debug('azure_zones: loading')
list_zones = self._dns_client.zones.list_by_resource_group
for zone in list_zones(self._resource_group):
self._azure_zones.add(zone.name.rstrip('.'))
def _check_zone(self, name, create=False):
'''Checks whether a zone specified in a source exist in Azure server.
Note that Azure zones omit end '.' eg: contoso.com vs contoso.com.
Returns the name if it exists.
:param name: Name of a zone to checks
:type name: str
:param create: If True, creates the zone of that name.
:type create: bool
:type return: str or None
'''
self.log.debug('_check_zone: name=%s create=%s', name, create)
# Check if the zone already exists in our set
if name in self._azure_zones:
return name
# If not, and its time to create, lets do it.
if create:
self.log.debug('_check_zone:no matching zone; creating %s', name)
create_zone = self._dns_client.zones.create_or_update
create_zone(self._resource_group, name, Zone(location='global'))
self._azure_zones.add(name)
return name
else:
# Else return nothing (aka false)
return
def populate(self, zone, target=False, lenient=False):
'''Required function of manager.py to collect records from zone.
Special notes for Azure.
Azure zone names omit final '.'
Azure root records names are represented by '@'. OctoDNS uses ''
Azure records created through online interface may have null values
(eg, no IP address for A record).
Azure online interface allows constructing records with null values
which are destroyed by _apply.
Specific quirks such as these are responsible for any non-obvious
parsing in this function and the functions '_params_for_*'.
:param zone: A dns zone
:type zone: octodns.zone.Zone
:param target: Checks if Azure is source or target of config.
Currently only supports as a target. Unused.
:type target: bool
:param lenient: Unused. Check octodns.manager for usage.
:type lenient: bool
:type return: void
'''
self.log.debug('populate: name=%s', zone.name)
exists = False
before = len(zone.records)
zone_name = zone.name[:len(zone.name) - 1]
self._populate_zones()
self._check_zone(zone_name)
_records = []
records = self._dns_client.record_sets.list_by_dns_zone
if self._check_zone(zone_name):
exists = True
for azrecord in records(self._resource_group, zone_name):
if _parse_azure_type(azrecord.type) in self.SUPPORTS:
_records.append(azrecord)
for azrecord in _records:
record_name = azrecord.name if azrecord.name != '@' else ''
typ = _parse_azure_type(azrecord.type)
if typ in ['A', 'CNAME']:
if _check_for_alias(azrecord):
self.log.debug(
'Skipping - ALIAS. zone=%s record=%s, type=%s',
zone_name, record_name, typ) # pragma: no cover
continue # pragma: no cover
data = getattr(self, '_data_for_{}'.format(typ))
data = data(azrecord)
data['type'] = typ
data['ttl'] = azrecord.ttl
record = Record.new(zone, record_name, data, source=self)
zone.add_record(record, lenient=lenient)
self.log.info('populate: found %s records, exists=%s',
len(zone.records) - before, exists)
return exists
def _data_for_A(self, azrecord):
return {'values': [ar.ipv4_address for ar in azrecord.a_records]}
def _data_for_AAAA(self, azrecord):
return {'values': [ar.ipv6_address for ar in azrecord.aaaa_records]}
def _data_for_CAA(self, azrecord):
return {'values': [{'flags': ar.flags,
'tag': ar.tag,
'value': ar.value}
for ar in azrecord.caa_records]}
def _data_for_CNAME(self, azrecord):
'''Parsing data from Azure DNS Client record call
:param azrecord: a return of a call to list azure records
:type azrecord: azure.mgmt.dns.models.RecordSet
:type return: dict
'''
return {'value': _check_endswith_dot(azrecord.cname_record.cname)}
def _data_for_MX(self, azrecord):
return {'values': [{'preference': ar.preference,
'exchange': ar.exchange}
for ar in azrecord.mx_records]}
def _data_for_NS(self, azrecord):
vals = [ar.nsdname for ar in azrecord.ns_records]
return {'values': [_check_endswith_dot(val) for val in vals]}
def _data_for_PTR(self, azrecord):
ptrdname = azrecord.ptr_records[0].ptrdname
return {'value': _check_endswith_dot(ptrdname)}
def _data_for_SRV(self, azrecord):
return {'values': [{'priority': ar.priority, 'weight': ar.weight,
'port': ar.port, 'target': ar.target}
for ar in azrecord.srv_records]}
def _data_for_TXT(self, azrecord):
return {'values': [escape_semicolon(reduce((lambda a, b: a + b),
ar.value))
for ar in azrecord.txt_records]}
def _apply_Create(self, change):
'''A record from change must be created.
:param change: a change object
:type change: octodns.record.Change
:type return: void
'''
ar = _AzureRecord(self._resource_group, change.new)
create = self._dns_client.record_sets.create_or_update
create(resource_group_name=ar.resource_group,
zone_name=ar.zone_name,
relative_record_set_name=ar.relative_record_set_name,
record_type=ar.record_type,
parameters=ar.params)
self.log.debug('* Success Create/Update: {}'.format(ar))
_apply_Update = _apply_Create
def _apply_Delete(self, change):
ar = _AzureRecord(self._resource_group, change.existing, delete=True)
delete = self._dns_client.record_sets.delete
delete(self._resource_group, ar.zone_name, ar.relative_record_set_name,
ar.record_type)
self.log.debug('* Success Delete: {}'.format(ar))
def _apply(self, plan):
'''Required function of manager.py to actually apply a record change.
:param plan: Contains the zones and changes to be made
:type plan: octodns.provider.base.Plan
:type return: void
'''
desired = plan.desired
changes = plan.changes
self.log.debug('_apply: zone=%s, len(changes)=%d', desired.name,
len(changes))
azure_zone_name = desired.name[:len(desired.name) - 1]
self._check_zone(azure_zone_name, create=True)
'''
Force the operation order to be Delete() before all other operations.
Helps avoid problems in updating
- a CNAME record into an A record.
- an A record into a CNAME record.
'''
for change in changes:
class_name = change.__class__.__name__
if class_name == 'Delete':
self._apply_Delete(change)
for change in changes:
class_name = change.__class__.__name__
if class_name != 'Delete':
getattr(self, '_apply_{}'.format(class_name))(change)