# (c) 2014, Brian Coca, Josh Drake, et al # (c) 2017 Ansible Project # GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt) from __future__ import (absolute_import, division, print_function) __metaclass__ = type DOCUMENTATION = ''' author: Unknown (!UNKNOWN) cache: redis short_description: Use Redis DB for cache description: - This cache uses JSON formatted, per host records saved in Redis. requirements: - redis>=2.4.5 (python lib) options: _uri: description: - A colon separated string of connection information for Redis. - The format is C(host:port:db:password), for example C(localhost:6379:0:changeme). - To use encryption in transit, prefix the connection with C(tls://), as in C(tls://localhost:6379:0:changeme). - To use redis sentinel, use separator C(;), for example C(localhost:26379;localhost:26379;0:changeme). Requires redis>=2.9.0. required: True env: - name: ANSIBLE_CACHE_PLUGIN_CONNECTION ini: - key: fact_caching_connection section: defaults _prefix: description: User defined prefix to use when creating the DB entries default: ansible_facts env: - name: ANSIBLE_CACHE_PLUGIN_PREFIX ini: - key: fact_caching_prefix section: defaults _keyset_name: description: User defined name for cache keyset name. default: ansible_cache_keys env: - name: ANSIBLE_CACHE_REDIS_KEYSET_NAME ini: - key: fact_caching_redis_keyset_name section: defaults version_added: 1.3.0 _sentinel_service_name: description: The redis sentinel service name (or referenced as cluster name). env: - name: ANSIBLE_CACHE_REDIS_SENTINEL ini: - key: fact_caching_redis_sentinel section: defaults version_added: 1.3.0 _timeout: default: 86400 description: Expiration timeout in seconds for the cache plugin data. Set to 0 to never expire env: - name: ANSIBLE_CACHE_PLUGIN_TIMEOUT ini: - key: fact_caching_timeout section: defaults type: integer ''' import time import json from ansible import constants as C from ansible.errors import AnsibleError from ansible.module_utils._text import to_native from ansible.parsing.ajson import AnsibleJSONEncoder, AnsibleJSONDecoder from ansible.plugins.cache import BaseCacheModule from ansible.utils.display import Display try: from redis import StrictRedis, VERSION HAS_REDIS = True except ImportError: HAS_REDIS = False display = Display() class CacheModule(BaseCacheModule): """ A caching module backed by redis. Keys are maintained in a zset with their score being the timestamp when they are inserted. This allows for the usage of 'zremrangebyscore' to expire keys. This mechanism is used or a pattern matched 'scan' for performance. """ _sentinel_service_name = None def __init__(self, *args, **kwargs): uri = '' try: super(CacheModule, self).__init__(*args, **kwargs) if self.get_option('_uri'): uri = self.get_option('_uri') self._timeout = float(self.get_option('_timeout')) self._prefix = self.get_option('_prefix') self._keys_set = self.get_option('_keyset_name') self._sentinel_service_name = self.get_option('_sentinel_service_name') except KeyError: display.deprecated('Rather than importing CacheModules directly, ' 'use ansible.plugins.loader.cache_loader', version='2.0.0', collection_name='community.general') # was Ansible 2.12 if C.CACHE_PLUGIN_CONNECTION: uri = C.CACHE_PLUGIN_CONNECTION self._timeout = float(C.CACHE_PLUGIN_TIMEOUT) self._prefix = C.CACHE_PLUGIN_PREFIX self._keys_set = 'ansible_cache_keys' if not HAS_REDIS: raise AnsibleError("The 'redis' python module (version 2.4.5 or newer) is required for the redis fact cache, 'pip install redis'") self._cache = {} kw = {} # tls connection tlsprefix = 'tls://' if uri.startswith(tlsprefix): kw['ssl'] = True uri = uri[len(tlsprefix):] # redis sentinel connection if self._sentinel_service_name: self._db = self._get_sentinel_connection(uri, kw) # normal connection else: connection = uri.split(':') self._db = StrictRedis(*connection, **kw) display.vv('Redis connection: %s' % self._db) def _get_sentinel_connection(self, uri, kw): """ get sentinel connection details from _uri """ try: from redis.sentinel import Sentinel except ImportError: raise AnsibleError("The 'redis' python module (version 2.9.0 or newer) is required to use redis sentinel.") if ';' not in uri: raise AnsibleError('_uri does not have sentinel syntax.') # format: "localhost:26379;localhost2:26379;0:changeme" connections = uri.split(';') connection_args = connections.pop(-1) if len(connection_args) > 0: # hanle if no db nr is given connection_args = connection_args.split(':') kw['db'] = connection_args.pop(0) try: kw['password'] = connection_args.pop(0) except IndexError: pass # password is optional sentinels = [tuple(shost.split(':')) for shost in connections] display.vv('\nUsing redis sentinels: %s' % sentinels) scon = Sentinel(sentinels, **kw) try: return scon.master_for(self._sentinel_service_name, socket_timeout=0.2) except Exception as exc: raise AnsibleError('Could not connect to redis sentinel: %s' % to_native(exc)) def _make_key(self, key): return self._prefix + key def get(self, key): if key not in self._cache: value = self._db.get(self._make_key(key)) # guard against the key not being removed from the zset; # this could happen in cases where the timeout value is changed # between invocations if value is None: self.delete(key) raise KeyError self._cache[key] = json.loads(value, cls=AnsibleJSONDecoder) return self._cache.get(key) def set(self, key, value): value2 = json.dumps(value, cls=AnsibleJSONEncoder, sort_keys=True, indent=4) if self._timeout > 0: # a timeout of 0 is handled as meaning 'never expire' self._db.setex(self._make_key(key), int(self._timeout), value2) else: self._db.set(self._make_key(key), value2) if VERSION[0] == 2: self._db.zadd(self._keys_set, time.time(), key) else: self._db.zadd(self._keys_set, {key: time.time()}) self._cache[key] = value def _expire_keys(self): if self._timeout > 0: expiry_age = time.time() - self._timeout self._db.zremrangebyscore(self._keys_set, 0, expiry_age) def keys(self): self._expire_keys() return self._db.zrange(self._keys_set, 0, -1) def contains(self, key): self._expire_keys() return (self._db.zrank(self._keys_set, key) is not None) def delete(self, key): if key in self._cache: del self._cache[key] self._db.delete(self._make_key(key)) self._db.zrem(self._keys_set, key) def flush(self): for key in list(self.keys()): self.delete(key) def copy(self): # TODO: there is probably a better way to do this in redis ret = dict([(k, self.get(k)) for k in self.keys()]) return ret def __getstate__(self): return dict() def __setstate__(self, data): self.__init__()