def test_repr(self):
from pyramid.util import Sentinel
r = repr(Sentinel('ABC'))
self.assertEqual(r, 'ABC')
TopologicalSorter,
FIRST,
LAST,
Sentinel,
)
from ..util import acquire
from ..interfaces import IUserLocator
from ..principal import DefaultUserLocator
LEFT = 'LEFT'
RIGHT = 'RIGHT'
MIDDLE = 'MIDDLE'
CENTER1 = Sentinel('CENTER1')
CENTER2 = Sentinel('CENTER2')
MANAGE_ROUTE_NAME = 'substanced_manage'
MAX_ORDER = 1 << 30
_marker = object()
@viewdefaults
@action_method
def add_mgmt_view(config,
view=None,
name="",
permission='sdi.view',
class RequestLocalCache:
"""
A store that caches values during for the lifecycle of a request.
Wrapping Functions
Instantiate and use it to decorate functions that accept a request
parameter. The result is cached and returned in subsequent invocations
of the function.
.. code-block:: python
@RequestLocalCache()
def get_user(request):
result = ... # do some expensive computations
return result
value = get_user(request)
# manipulate the cache directly
get_user.cache.clear(request)
The cache instance is attached to the resulting function as the ``cache``
attribute such that the function may be used to manipulate the cache.
Wrapping Methods
A method can be used as the creator function but it needs to be bound to
an instance such that it only accepts one argument - the request. An easy
way to do this is to bind the creator in the constructor and then use
:meth:`.get_or_create`:
.. code-block:: python
class SecurityPolicy:
def __init__(self):
self.identity_cache = RequestLocalCache(self.load_identity)
def load_identity(self, request):
result = ... # do some expensive computations
return result
def authenticated_identity(self, request):
return self.identity_cache.get_or_create(request)
The cache maintains a weakref to each request and will release the cached
values when the request is garbage-collected. However, in most scenarios,
it will release resources earlier via
:meth:`pyramid.request.Request.add_finished_callback`.
.. versionadded:: 2.0
"""
NO_VALUE = Sentinel('NO_VALUE')
def __init__(self, creator=None):
self._store = weakref.WeakKeyDictionary()
self._creator = creator
def __call__(self, fn):
@functools.wraps(fn)
def wrapper(request):
return wrapper.cache.get_or_create(request, fn)
wrapper.cache = self
self._creator = fn
return wrapper
def get_or_create(self, request, creator=None):
"""
Return the value from the cache. Compute if necessary.
If no value is cached then execute the creator, cache the result,
and return it.
The creator may be passed in as an argument or bound to the cache
by decorating a function or supplied as a constructor argument.
"""
result = self._store.get(request, self.NO_VALUE)
if result is self.NO_VALUE:
if creator is None:
creator = self._creator
if creator is None:
raise ValueError(
'no creator function has been registered with the '
'cache or supplied to "get_or_create"')
result = creator(request)
self.set(request, result)
return result
def get(self, request, default=NO_VALUE):
"""
Return the value from the cache.
The cached value is returned or ``default``.
"""
return self._store.get(request, default)
def set(self, request, value):
"""
Update the cache with a new value.
"""
already_set = request in self._store
self._store[request] = value
# avoid registering the callback more than once
if not already_set:
request.add_finished_callback(self._store.pop)
def clear(self, request):
"""
Delete the value from the cache.
The cached value is returned or :attr:`.NO_VALUE`.
"""
old_value = self.NO_VALUE
if request in self._store:
old_value = self._store[request]
# keep a value in the store so that we don't register another
# finished callback when set is invoked
self._store[request] = self.NO_VALUE
return old_value
authenticated_userid,
has_permission,
)
from pyramid.session import UnencryptedCookieSessionFactoryConfig
from pyramid.traversal import resource_path_tuple
from pyramid.util import (
action_method,
viewdefaults,
TopologicalSorter,
FIRST,
LAST,
Sentinel,
)
MIDDLE = Sentinel('MIDDLE')
from ..objectmap import find_objectmap
MANAGE_ROUTE_NAME = 'substanced_manage'
_marker = object()
@viewdefaults
@action_method
def add_mgmt_view(config,
view=None,
name="",
permission=None,
request_type=None,