def test_weakfuncref_method():
class Thing(object):
def method(self):
return 'existent!'
def __priv_method(self):
return 'existent!'
@classmethod
def clsmethod(clsself):
return 'existent!'
t = Thing()
gcd_methref = make_weakfuncref_that_will_get_gcd()
methref = weakfuncref.WeakFunctionRef(t.method)
privmethref = weakfuncref.WeakFunctionRef(t._Thing__priv_method)
clsmethref = weakfuncref.WeakFunctionRef(t.clsmethod)
assert gcd_methref.function() is None
assert privmethref.function()() == 'existent!'
assert methref.function()() == 'existent!'
assert clsmethref.function()() == 'existent!'
print(gcd_methref)
print(methref)
t = None
assert methref.function() is None
assert privmethref.function() is None
assert clsmethref.function()() == 'existent!'
def __init__(self, target, propNames, keyFunc, triggers):
"""Create a ``PropCache``.
:arg target: Target :class:`.HasProperties` instance whose
property values are to be cached.
:arg propNames: Names of properties on the ``target`` to be cached
:arg keyFunc: Function which will be called whenever a trigger
property changes, to generate a suitable key to
use for cached property values.
:arg triggers: Sequence of ``(hasProps, propName)`` pairs, specifying
which property changes should trigger caching of
the ``target`` property values.
"""
self.__name = '{}_{}'.format(type(self).__name__, id(self))
self.__cache = {}
self.__target = weakref.ref(target)
self.__propNames = propNames
self.__keyFunc = weakfuncref.WeakFunctionRef(keyFunc)
self.__triggers = [(weakref.ref(tobj), tprop)
for (tobj, tprop) in triggers]
for tobj, tprop in triggers:
tobj.addListener(tprop,
self.__name,
self.__doCache,
immediate=True)
def addAttributeListener(self, name, listener, weak=True, immediate=False):
"""Adds an attribute listener for this ``PropertyValue``. The
listener callback function must accept the following arguments:
- ``context``: The context associated with this ``PropertyValue``.
- ``attribute``: The name of the attribute that changed.
- ``value``: The new attribute value.
- ``name``: The name of this ``PropertyValue`` instance.
:param name: A unique name for the listener. If a listener with
the specified name already exists, it will be
overwritten.
:param listener: The callback function.
:param weak: If ``True`` (the default), a weak reference to the
callback function is used.
:param immediate: If ``False`` (the default), the listener is called
immediately; otherwise, it is called via the
:attr:`queue`.
"""
log.debug('Adding attribute listener on {}.{} ({}): {}'.format(
self._context().__class__.__name__, self._name, id(self), name))
if weak:
listener = weakfuncref.WeakFunctionRef(listener)
name = self.__saltListenerName(name)
self._attributeListeners[name] = Listener(self, name, listener, True,
immediate)
def test_weakfuncref_function():
def func():
pass
non_gcd_func = weakfuncref.WeakFunctionRef(func)
gcd_func = make_weakfuncref_that_will_get_gcd()
assert gcd_func.function() is None
assert non_gcd_func.function() is func
def __init__(self, name, callback, topic, runOnIdle):
self.name = name
# We use a WeakFunctionRef so we can refer to
# both functions and class/instance methods
self.__callback = weakfuncref.WeakFunctionRef(callback)
self.topic = topic
self.runOnIdle = runOnIdle
self.enabled = True
def make_weakfuncref_method_that_will_get_gcd():
class Thing(object):
def method(self):
pass
return weakfuncref.WeakFunctionRef(Thing.method)
def make_weakfuncref_that_will_get_gcd():
def thefunc():
pass
return weakfuncref.WeakFunctionRef(thefunc)
def addListener(self,
name,
callback,
overwrite=False,
weak=True,
immediate=False):
"""Adds a listener for this value.
When the value changes, the listener callback function is called. The
callback function must accept the following arguments:
- ``value``: The property value
- ``valid``: Whether the value is valid or invalid
- ``context``: The context object passed to :meth:`__init__`.
- ``name``: The name of this ``PropertyValue`` instance.
Listener names ``prenotify`` and ``postnotify`` are reserved - if
either of these are passed in for the listener name, a :exc`ValueError`
is raised.
:param str name: A unique name for this listener. If a listener with
the name already exists, a :exc`RuntimeError` will be
raised, or it will be overwritten, depending upon
the value of the ``overwrite`` argument.
:param callback: The callback function.
:param overwrite: If ``True`` any previous listener with the same name
will be overwritten.
:param weak: If ``True`` (the default), a weak reference to the
callback function is retained, meaning that it
can be garbage-collected. If passing in a lambda or
inner function, you will probably want to set
``weak`` to ``False``, in which case a strong
reference will be used.
:param immediate: If ``False`` (the default), this listener will be
notified through the :class:`.CallQueue` - listeners
for all ``PropertyValue`` instances are queued, and
notified in turn. If ``True``, If ``True``, the
``CallQueue`` will not be used, and this listener
will be notified as soon as this ``PropertyValue``
changes.
"""
if name in ('prenotify', 'postnotify'):
raise ValueError('Reserved listener name used: {}. '
'Use a different name.'.format(name))
log.debug('Adding listener on {}.{}: {}'.format(
self._context().__class__.__name__, self._name, name))
fullName = self.__saltListenerName(name)
prior = self._changeListeners.get(fullName, None)
if weak:
callback = weakfuncref.WeakFunctionRef(callback)
if (prior is not None) and (not overwrite):
raise RuntimeError('Listener {} already exists'.format(name))
elif prior is not None:
prior.function = callback
prior.immediate = immediate
else:
self._changeListeners[fullName] = Listener(self, fullName,
callback, True,
immediate)
