def _get_resolver_config_cache():
"""
helper - common getter to access the resolver_config cache
the resolver config cache is used to track the resolver configuration
changes. therefore for each resolver spec the resolver config is stored
in a cache. In case of an request the comparison of the resolver config
with the cache value is made and in case of inconsistancy the resolver
user cache is flushed.
:remark: This cache is only enabled, if the resolver user lookup cache
is enabled too
:return: the resolver config cache
"""
config = context['Config']
enabled = config.get('linotp.resolver_lookup_cache.enabled',
'True') == 'True'
if not enabled:
return None
try:
expiration_conf = config.get('linotp.resolver_lookup_cache.expiration',
36 * 3600)
expiration = get_duration(expiration_conf)
except ValueError:
log.info("resolver caching is disabled due to a value error in "
"resolver_lookup_cache.expiration config")
return None
cache_manager = current_app.getCacheManager()
if not cache_manager:
return None
cache_name = 'resolver_config'
resolver_config_cache = cache_manager.get_cache(cache_name,
type="memory",
expiretime=expiration)
return resolver_config_cache
def get_cache(cache_name: str, scope: str = None) -> Optional[Cache]:
"""
load the cache with cache_name and scope
Each cache defines the following configuration parameters:
linotp.{cache_name}_cache.enabled
Whether the cache is enabled. Defaults to True
linotp.{cache_name}_cache.expiration
How long the entries are cached for in seconds. Defaults to 3 days.
:remark: This cache is only enabled, if the configuration entry 'enabled'
evaluates to True and the expiration is of a valid format.
Expiration format is defined linotp.lib.type_utils
:param cache_name: the name of the cache
:param scope: there are related caches, which names are extended by scope
used for realm specific caches e.g. for users
:return: the cache or None if not enabled,
wrt to typing the cache is not deterministic as the cache type
is returned by the app.getCacheManager() which could be a beaker
or something else
"""
# --------------------------------------------------------------------- --
# evaluate the config lookup keys
config = context["Config"]
config_basename = "linotp." + cache_name + "_cache"
enabled_entry = config_basename + ".enabled"
expiration_entry = config_basename + ".expiration"
# --------------------------------------------------------------------- --
enabled = boolean(config.get(enabled_entry, True))
if not enabled:
return None
# --------------------------------------------------------------------- --
# handle expiration format
expiration_conf = config.get(expiration_entry, 36 * 3600)
try:
expiration = get_duration(expiration_conf)
except ValueError:
log.info(
"caching is disabled due to a value error for expiration "
"definition %r",
expiration_conf,
)
return None
# --------------------------------------------------------------------- --
# retrieve the cache from the cache manager
cache_manager = current_app.getCacheManager()
if not cache_manager:
log.info("No Cache Manager found!")
return None
cache_fullname = cache_name
if scope:
cache_fullname = "%s::%s" % (cache_name, scope)
resolver_config_cache = cache_manager.get_cache(cache_fullname,
type="memory",
expiretime=expiration)
return resolver_config_cache