mirror of
https://github.com/janeczku/calibre-web
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Initial Fork from https://bitbucket.org/raphaelmutschler/calibreserver/
This commit is contained in:
22
lib/blinker/__init__.py
Normal file
22
lib/blinker/__init__.py
Normal file
@@ -0,0 +1,22 @@
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||||
from blinker.base import (
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||||
ANY,
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||||
NamedSignal,
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Namespace,
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Signal,
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WeakNamespace,
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receiver_connected,
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||||
signal,
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||||
)
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||||
|
||||
__all__ = [
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'ANY',
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'NamedSignal',
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'Namespace',
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'Signal',
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'WeakNamespace',
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'receiver_connected',
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'signal',
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]
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__version__ = '1.3'
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234
lib/blinker/_saferef.py
Normal file
234
lib/blinker/_saferef.py
Normal file
@@ -0,0 +1,234 @@
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# extracted from Louie, http://pylouie.org/
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# updated for Python 3
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#
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||||
# Copyright (c) 2006 Patrick K. O'Brien, Mike C. Fletcher,
|
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# Matthew R. Scott
|
||||
#
|
||||
# Redistribution and use in source and binary forms, with or without
|
||||
# modification, are permitted provided that the following conditions are
|
||||
# met:
|
||||
#
|
||||
# * Redistributions of source code must retain the above copyright
|
||||
# notice, this list of conditions and the following disclaimer.
|
||||
#
|
||||
# * Redistributions in binary form must reproduce the above
|
||||
# copyright notice, this list of conditions and the following
|
||||
# disclaimer in the documentation and/or other materials provided
|
||||
# with the distribution.
|
||||
#
|
||||
# * Neither the name of the <ORGANIZATION> nor the names of its
|
||||
# contributors may be used to endorse or promote products derived
|
||||
# from this software without specific prior written permission.
|
||||
#
|
||||
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
||||
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
||||
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
|
||||
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
|
||||
# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
||||
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
||||
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
||||
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
||||
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
||||
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
||||
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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||||
#
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"""Refactored 'safe reference from dispatcher.py"""
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import operator
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import sys
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import traceback
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import weakref
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||||
|
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||||
try:
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||||
callable
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||||
except NameError:
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||||
def callable(object):
|
||||
return hasattr(object, '__call__')
|
||||
|
||||
|
||||
if sys.version_info < (3,):
|
||||
get_self = operator.attrgetter('im_self')
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||||
get_func = operator.attrgetter('im_func')
|
||||
else:
|
||||
get_self = operator.attrgetter('__self__')
|
||||
get_func = operator.attrgetter('__func__')
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||||
|
||||
|
||||
def safe_ref(target, on_delete=None):
|
||||
"""Return a *safe* weak reference to a callable target.
|
||||
|
||||
- ``target``: The object to be weakly referenced, if it's a bound
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||||
method reference, will create a BoundMethodWeakref, otherwise
|
||||
creates a simple weakref.
|
||||
|
||||
- ``on_delete``: If provided, will have a hard reference stored to
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||||
the callable to be called after the safe reference goes out of
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scope with the reference object, (either a weakref or a
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||||
BoundMethodWeakref) as argument.
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"""
|
||||
try:
|
||||
im_self = get_self(target)
|
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except AttributeError:
|
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if callable(on_delete):
|
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return weakref.ref(target, on_delete)
|
||||
else:
|
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return weakref.ref(target)
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||||
else:
|
||||
if im_self is not None:
|
||||
# Turn a bound method into a BoundMethodWeakref instance.
|
||||
# Keep track of these instances for lookup by disconnect().
|
||||
assert hasattr(target, 'im_func') or hasattr(target, '__func__'), (
|
||||
"safe_ref target %r has im_self, but no im_func, "
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||||
"don't know how to create reference" % target)
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reference = BoundMethodWeakref(target=target, on_delete=on_delete)
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return reference
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class BoundMethodWeakref(object):
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"""'Safe' and reusable weak references to instance methods.
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||||
BoundMethodWeakref objects provide a mechanism for referencing a
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bound method without requiring that the method object itself
|
||||
(which is normally a transient object) is kept alive. Instead,
|
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the BoundMethodWeakref object keeps weak references to both the
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object and the function which together define the instance method.
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||||
|
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Attributes:
|
||||
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- ``key``: The identity key for the reference, calculated by the
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||||
class's calculate_key method applied to the target instance method.
|
||||
|
||||
- ``deletion_methods``: Sequence of callable objects taking single
|
||||
argument, a reference to this object which will be called when
|
||||
*either* the target object or target function is garbage
|
||||
collected (i.e. when this object becomes invalid). These are
|
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specified as the on_delete parameters of safe_ref calls.
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||||
|
||||
- ``weak_self``: Weak reference to the target object.
|
||||
|
||||
- ``weak_func``: Weak reference to the target function.
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||||
|
||||
Class Attributes:
|
||||
|
||||
- ``_all_instances``: Class attribute pointing to all live
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BoundMethodWeakref objects indexed by the class's
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||||
calculate_key(target) method applied to the target objects.
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This weak value dictionary is used to short-circuit creation so
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that multiple references to the same (object, function) pair
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||||
produce the same BoundMethodWeakref instance.
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||||
"""
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||||
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||||
_all_instances = weakref.WeakValueDictionary()
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||||
|
||||
def __new__(cls, target, on_delete=None, *arguments, **named):
|
||||
"""Create new instance or return current instance.
|
||||
|
||||
Basically this method of construction allows us to
|
||||
short-circuit creation of references to already- referenced
|
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instance methods. The key corresponding to the target is
|
||||
calculated, and if there is already an existing reference,
|
||||
that is returned, with its deletion_methods attribute updated.
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||||
Otherwise the new instance is created and registered in the
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||||
table of already-referenced methods.
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||||
"""
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key = cls.calculate_key(target)
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||||
current = cls._all_instances.get(key)
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||||
if current is not None:
|
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current.deletion_methods.append(on_delete)
|
||||
return current
|
||||
else:
|
||||
base = super(BoundMethodWeakref, cls).__new__(cls)
|
||||
cls._all_instances[key] = base
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||||
base.__init__(target, on_delete, *arguments, **named)
|
||||
return base
|
||||
|
||||
def __init__(self, target, on_delete=None):
|
||||
"""Return a weak-reference-like instance for a bound method.
|
||||
|
||||
- ``target``: The instance-method target for the weak reference,
|
||||
must have im_self and im_func attributes and be
|
||||
reconstructable via the following, which is true of built-in
|
||||
instance methods::
|
||||
|
||||
target.im_func.__get__( target.im_self )
|
||||
|
||||
- ``on_delete``: Optional callback which will be called when
|
||||
this weak reference ceases to be valid (i.e. either the
|
||||
object or the function is garbage collected). Should take a
|
||||
single argument, which will be passed a pointer to this
|
||||
object.
|
||||
"""
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||||
def remove(weak, self=self):
|
||||
"""Set self.isDead to True when method or instance is destroyed."""
|
||||
methods = self.deletion_methods[:]
|
||||
del self.deletion_methods[:]
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||||
try:
|
||||
del self.__class__._all_instances[self.key]
|
||||
except KeyError:
|
||||
pass
|
||||
for function in methods:
|
||||
try:
|
||||
if callable(function):
|
||||
function(self)
|
||||
except Exception:
|
||||
try:
|
||||
traceback.print_exc()
|
||||
except AttributeError:
|
||||
e = sys.exc_info()[1]
|
||||
print ('Exception during saferef %s '
|
||||
'cleanup function %s: %s' % (self, function, e))
|
||||
self.deletion_methods = [on_delete]
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||||
self.key = self.calculate_key(target)
|
||||
im_self = get_self(target)
|
||||
im_func = get_func(target)
|
||||
self.weak_self = weakref.ref(im_self, remove)
|
||||
self.weak_func = weakref.ref(im_func, remove)
|
||||
self.self_name = str(im_self)
|
||||
self.func_name = str(im_func.__name__)
|
||||
|
||||
def calculate_key(cls, target):
|
||||
"""Calculate the reference key for this reference.
|
||||
|
||||
Currently this is a two-tuple of the id()'s of the target
|
||||
object and the target function respectively.
|
||||
"""
|
||||
return (id(get_self(target)), id(get_func(target)))
|
||||
calculate_key = classmethod(calculate_key)
|
||||
|
||||
def __str__(self):
|
||||
"""Give a friendly representation of the object."""
|
||||
return "%s(%s.%s)" % (
|
||||
self.__class__.__name__,
|
||||
self.self_name,
|
||||
self.func_name,
|
||||
)
|
||||
|
||||
__repr__ = __str__
|
||||
|
||||
def __nonzero__(self):
|
||||
"""Whether we are still a valid reference."""
|
||||
return self() is not None
|
||||
|
||||
def __cmp__(self, other):
|
||||
"""Compare with another reference."""
|
||||
if not isinstance(other, self.__class__):
|
||||
return cmp(self.__class__, type(other))
|
||||
return cmp(self.key, other.key)
|
||||
|
||||
def __call__(self):
|
||||
"""Return a strong reference to the bound method.
|
||||
|
||||
If the target cannot be retrieved, then will return None,
|
||||
otherwise returns a bound instance method for our object and
|
||||
function.
|
||||
|
||||
Note: You may call this method any number of times, as it does
|
||||
not invalidate the reference.
|
||||
"""
|
||||
target = self.weak_self()
|
||||
if target is not None:
|
||||
function = self.weak_func()
|
||||
if function is not None:
|
||||
return function.__get__(target)
|
||||
return None
|
||||
163
lib/blinker/_utilities.py
Normal file
163
lib/blinker/_utilities.py
Normal file
@@ -0,0 +1,163 @@
|
||||
from weakref import ref
|
||||
|
||||
from blinker._saferef import BoundMethodWeakref
|
||||
|
||||
|
||||
try:
|
||||
callable
|
||||
except NameError:
|
||||
def callable(object):
|
||||
return hasattr(object, '__call__')
|
||||
|
||||
|
||||
try:
|
||||
from collections import defaultdict
|
||||
except:
|
||||
class defaultdict(dict):
|
||||
|
||||
def __init__(self, default_factory=None, *a, **kw):
|
||||
if (default_factory is not None and
|
||||
not hasattr(default_factory, '__call__')):
|
||||
raise TypeError('first argument must be callable')
|
||||
dict.__init__(self, *a, **kw)
|
||||
self.default_factory = default_factory
|
||||
|
||||
def __getitem__(self, key):
|
||||
try:
|
||||
return dict.__getitem__(self, key)
|
||||
except KeyError:
|
||||
return self.__missing__(key)
|
||||
|
||||
def __missing__(self, key):
|
||||
if self.default_factory is None:
|
||||
raise KeyError(key)
|
||||
self[key] = value = self.default_factory()
|
||||
return value
|
||||
|
||||
def __reduce__(self):
|
||||
if self.default_factory is None:
|
||||
args = tuple()
|
||||
else:
|
||||
args = self.default_factory,
|
||||
return type(self), args, None, None, self.items()
|
||||
|
||||
def copy(self):
|
||||
return self.__copy__()
|
||||
|
||||
def __copy__(self):
|
||||
return type(self)(self.default_factory, self)
|
||||
|
||||
def __deepcopy__(self, memo):
|
||||
import copy
|
||||
return type(self)(self.default_factory,
|
||||
copy.deepcopy(self.items()))
|
||||
|
||||
def __repr__(self):
|
||||
return 'defaultdict(%s, %s)' % (self.default_factory,
|
||||
dict.__repr__(self))
|
||||
|
||||
|
||||
try:
|
||||
from contextlib import contextmanager
|
||||
except ImportError:
|
||||
def contextmanager(fn):
|
||||
def oops(*args, **kw):
|
||||
raise RuntimeError("Python 2.5 or above is required to use "
|
||||
"context managers.")
|
||||
oops.__name__ = fn.__name__
|
||||
return oops
|
||||
|
||||
class _symbol(object):
|
||||
|
||||
def __init__(self, name):
|
||||
"""Construct a new named symbol."""
|
||||
self.__name__ = self.name = name
|
||||
|
||||
def __reduce__(self):
|
||||
return symbol, (self.name,)
|
||||
|
||||
def __repr__(self):
|
||||
return self.name
|
||||
_symbol.__name__ = 'symbol'
|
||||
|
||||
|
||||
class symbol(object):
|
||||
"""A constant symbol.
|
||||
|
||||
>>> symbol('foo') is symbol('foo')
|
||||
True
|
||||
>>> symbol('foo')
|
||||
foo
|
||||
|
||||
A slight refinement of the MAGICCOOKIE=object() pattern. The primary
|
||||
advantage of symbol() is its repr(). They are also singletons.
|
||||
|
||||
Repeated calls of symbol('name') will all return the same instance.
|
||||
|
||||
"""
|
||||
symbols = {}
|
||||
|
||||
def __new__(cls, name):
|
||||
try:
|
||||
return cls.symbols[name]
|
||||
except KeyError:
|
||||
return cls.symbols.setdefault(name, _symbol(name))
|
||||
|
||||
|
||||
try:
|
||||
text = (str, unicode)
|
||||
except NameError:
|
||||
text = str
|
||||
|
||||
|
||||
def hashable_identity(obj):
|
||||
if hasattr(obj, '__func__'):
|
||||
return (id(obj.__func__), id(obj.__self__))
|
||||
elif hasattr(obj, 'im_func'):
|
||||
return (id(obj.im_func), id(obj.im_self))
|
||||
elif isinstance(obj, text):
|
||||
return obj
|
||||
else:
|
||||
return id(obj)
|
||||
|
||||
|
||||
WeakTypes = (ref, BoundMethodWeakref)
|
||||
|
||||
|
||||
class annotatable_weakref(ref):
|
||||
"""A weakref.ref that supports custom instance attributes."""
|
||||
|
||||
|
||||
def reference(object, callback=None, **annotations):
|
||||
"""Return an annotated weak ref."""
|
||||
if callable(object):
|
||||
weak = callable_reference(object, callback)
|
||||
else:
|
||||
weak = annotatable_weakref(object, callback)
|
||||
for key, value in annotations.items():
|
||||
setattr(weak, key, value)
|
||||
return weak
|
||||
|
||||
|
||||
def callable_reference(object, callback=None):
|
||||
"""Return an annotated weak ref, supporting bound instance methods."""
|
||||
if hasattr(object, 'im_self') and object.im_self is not None:
|
||||
return BoundMethodWeakref(target=object, on_delete=callback)
|
||||
elif hasattr(object, '__self__') and object.__self__ is not None:
|
||||
return BoundMethodWeakref(target=object, on_delete=callback)
|
||||
return annotatable_weakref(object, callback)
|
||||
|
||||
|
||||
class lazy_property(object):
|
||||
"""A @property that is only evaluated once."""
|
||||
|
||||
def __init__(self, deferred):
|
||||
self._deferred = deferred
|
||||
self.__doc__ = deferred.__doc__
|
||||
|
||||
def __get__(self, obj, cls):
|
||||
if obj is None:
|
||||
return self
|
||||
value = self._deferred(obj)
|
||||
setattr(obj, self._deferred.__name__, value)
|
||||
return value
|
||||
426
lib/blinker/base.py
Normal file
426
lib/blinker/base.py
Normal file
@@ -0,0 +1,426 @@
|
||||
# -*- coding: utf-8; fill-column: 76 -*-
|
||||
"""Signals and events.
|
||||
|
||||
A small implementation of signals, inspired by a snippet of Django signal
|
||||
API client code seen in a blog post. Signals are first-class objects and
|
||||
each manages its own receivers and message emission.
|
||||
|
||||
The :func:`signal` function provides singleton behavior for named signals.
|
||||
|
||||
"""
|
||||
from warnings import warn
|
||||
from weakref import WeakValueDictionary
|
||||
|
||||
from blinker._utilities import (
|
||||
WeakTypes,
|
||||
contextmanager,
|
||||
defaultdict,
|
||||
hashable_identity,
|
||||
lazy_property,
|
||||
reference,
|
||||
symbol,
|
||||
)
|
||||
|
||||
|
||||
ANY = symbol('ANY')
|
||||
ANY.__doc__ = 'Token for "any sender".'
|
||||
ANY_ID = 0
|
||||
|
||||
|
||||
class Signal(object):
|
||||
"""A notification emitter."""
|
||||
|
||||
#: An :obj:`ANY` convenience synonym, allows ``Signal.ANY``
|
||||
#: without an additional import.
|
||||
ANY = ANY
|
||||
|
||||
@lazy_property
|
||||
def receiver_connected(self):
|
||||
"""Emitted after each :meth:`connect`.
|
||||
|
||||
The signal sender is the signal instance, and the :meth:`connect`
|
||||
arguments are passed through: *receiver*, *sender*, and *weak*.
|
||||
|
||||
.. versionadded:: 1.2
|
||||
|
||||
"""
|
||||
return Signal(doc="Emitted after a receiver connects.")
|
||||
|
||||
@lazy_property
|
||||
def receiver_disconnected(self):
|
||||
"""Emitted after :meth:`disconnect`.
|
||||
|
||||
The sender is the signal instance, and the :meth:`disconnect` arguments
|
||||
are passed through: *receiver* and *sender*.
|
||||
|
||||
Note, this signal is emitted **only** when :meth:`disconnect` is
|
||||
called explicitly.
|
||||
|
||||
The disconnect signal can not be emitted by an automatic disconnect
|
||||
(due to a weakly referenced receiver or sender going out of scope),
|
||||
as the receiver and/or sender instances are no longer available for
|
||||
use at the time this signal would be emitted.
|
||||
|
||||
An alternative approach is available by subscribing to
|
||||
:attr:`receiver_connected` and setting up a custom weakref cleanup
|
||||
callback on weak receivers and senders.
|
||||
|
||||
.. versionadded:: 1.2
|
||||
|
||||
"""
|
||||
return Signal(doc="Emitted after a receiver disconnects.")
|
||||
|
||||
def __init__(self, doc=None):
|
||||
"""
|
||||
:param doc: optional. If provided, will be assigned to the signal's
|
||||
__doc__ attribute.
|
||||
|
||||
"""
|
||||
if doc:
|
||||
self.__doc__ = doc
|
||||
#: A mapping of connected receivers.
|
||||
#:
|
||||
#: The values of this mapping are not meaningful outside of the
|
||||
#: internal :class:`Signal` implementation, however the boolean value
|
||||
#: of the mapping is useful as an extremely efficient check to see if
|
||||
#: any receivers are connected to the signal.
|
||||
self.receivers = {}
|
||||
self._by_receiver = defaultdict(set)
|
||||
self._by_sender = defaultdict(set)
|
||||
self._weak_senders = {}
|
||||
|
||||
def connect(self, receiver, sender=ANY, weak=True):
|
||||
"""Connect *receiver* to signal events sent by *sender*.
|
||||
|
||||
:param receiver: A callable. Will be invoked by :meth:`send` with
|
||||
`sender=` as a single positional argument and any \*\*kwargs that
|
||||
were provided to a call to :meth:`send`.
|
||||
|
||||
:param sender: Any object or :obj:`ANY`, defaults to ``ANY``.
|
||||
Restricts notifications delivered to *receiver* to only those
|
||||
:meth:`send` emissions sent by *sender*. If ``ANY``, the receiver
|
||||
will always be notified. A *receiver* may be connected to
|
||||
multiple *sender* values on the same Signal through multiple calls
|
||||
to :meth:`connect`.
|
||||
|
||||
:param weak: If true, the Signal will hold a weakref to *receiver*
|
||||
and automatically disconnect when *receiver* goes out of scope or
|
||||
is garbage collected. Defaults to True.
|
||||
|
||||
"""
|
||||
receiver_id = hashable_identity(receiver)
|
||||
if weak:
|
||||
receiver_ref = reference(receiver, self._cleanup_receiver)
|
||||
receiver_ref.receiver_id = receiver_id
|
||||
else:
|
||||
receiver_ref = receiver
|
||||
if sender is ANY:
|
||||
sender_id = ANY_ID
|
||||
else:
|
||||
sender_id = hashable_identity(sender)
|
||||
|
||||
self.receivers.setdefault(receiver_id, receiver_ref)
|
||||
self._by_sender[sender_id].add(receiver_id)
|
||||
self._by_receiver[receiver_id].add(sender_id)
|
||||
del receiver_ref
|
||||
|
||||
if sender is not ANY and sender_id not in self._weak_senders:
|
||||
# wire together a cleanup for weakref-able senders
|
||||
try:
|
||||
sender_ref = reference(sender, self._cleanup_sender)
|
||||
sender_ref.sender_id = sender_id
|
||||
except TypeError:
|
||||
pass
|
||||
else:
|
||||
self._weak_senders.setdefault(sender_id, sender_ref)
|
||||
del sender_ref
|
||||
|
||||
# broadcast this connection. if receivers raise, disconnect.
|
||||
if ('receiver_connected' in self.__dict__ and
|
||||
self.receiver_connected.receivers):
|
||||
try:
|
||||
self.receiver_connected.send(self,
|
||||
receiver=receiver,
|
||||
sender=sender,
|
||||
weak=weak)
|
||||
except:
|
||||
self.disconnect(receiver, sender)
|
||||
raise
|
||||
if receiver_connected.receivers and self is not receiver_connected:
|
||||
try:
|
||||
receiver_connected.send(self,
|
||||
receiver_arg=receiver,
|
||||
sender_arg=sender,
|
||||
weak_arg=weak)
|
||||
except:
|
||||
self.disconnect(receiver, sender)
|
||||
raise
|
||||
return receiver
|
||||
|
||||
def connect_via(self, sender, weak=False):
|
||||
"""Connect the decorated function as a receiver for *sender*.
|
||||
|
||||
:param sender: Any object or :obj:`ANY`. The decorated function
|
||||
will only receive :meth:`send` emissions sent by *sender*. If
|
||||
``ANY``, the receiver will always be notified. A function may be
|
||||
decorated multiple times with differing *sender* values.
|
||||
|
||||
:param weak: If true, the Signal will hold a weakref to the
|
||||
decorated function and automatically disconnect when *receiver*
|
||||
goes out of scope or is garbage collected. Unlike
|
||||
:meth:`connect`, this defaults to False.
|
||||
|
||||
The decorated function will be invoked by :meth:`send` with
|
||||
`sender=` as a single positional argument and any \*\*kwargs that
|
||||
were provided to the call to :meth:`send`.
|
||||
|
||||
|
||||
.. versionadded:: 1.1
|
||||
|
||||
"""
|
||||
def decorator(fn):
|
||||
self.connect(fn, sender, weak)
|
||||
return fn
|
||||
return decorator
|
||||
|
||||
@contextmanager
|
||||
def connected_to(self, receiver, sender=ANY):
|
||||
"""Execute a block with the signal temporarily connected to *receiver*.
|
||||
|
||||
:param receiver: a receiver callable
|
||||
:param sender: optional, a sender to filter on
|
||||
|
||||
This is a context manager for use in the ``with`` statement. It can
|
||||
be useful in unit tests. *receiver* is connected to the signal for
|
||||
the duration of the ``with`` block, and will be disconnected
|
||||
automatically when exiting the block:
|
||||
|
||||
.. testsetup::
|
||||
|
||||
from __future__ import with_statement
|
||||
from blinker import Signal
|
||||
on_ready = Signal()
|
||||
receiver = lambda sender: None
|
||||
|
||||
.. testcode::
|
||||
|
||||
with on_ready.connected_to(receiver):
|
||||
# do stuff
|
||||
on_ready.send(123)
|
||||
|
||||
.. versionadded:: 1.1
|
||||
|
||||
"""
|
||||
self.connect(receiver, sender=sender, weak=False)
|
||||
try:
|
||||
yield None
|
||||
except:
|
||||
self.disconnect(receiver)
|
||||
raise
|
||||
else:
|
||||
self.disconnect(receiver)
|
||||
|
||||
def temporarily_connected_to(self, receiver, sender=ANY):
|
||||
"""An alias for :meth:`connected_to`.
|
||||
|
||||
:param receiver: a receiver callable
|
||||
:param sender: optional, a sender to filter on
|
||||
|
||||
.. versionadded:: 0.9
|
||||
|
||||
.. versionchanged:: 1.1
|
||||
Renamed to :meth:`connected_to`. ``temporarily_connected_to``
|
||||
was deprecated in 1.2 and removed in a subsequent version.
|
||||
|
||||
"""
|
||||
warn("temporarily_connected_to is deprecated; "
|
||||
"use connected_to instead.",
|
||||
DeprecationWarning)
|
||||
return self.connected_to(receiver, sender)
|
||||
|
||||
def send(self, *sender, **kwargs):
|
||||
"""Emit this signal on behalf of *sender*, passing on \*\*kwargs.
|
||||
|
||||
Returns a list of 2-tuples, pairing receivers with their return
|
||||
value. The ordering of receiver notification is undefined.
|
||||
|
||||
:param \*sender: Any object or ``None``. If omitted, synonymous
|
||||
with ``None``. Only accepts one positional argument.
|
||||
|
||||
:param \*\*kwargs: Data to be sent to receivers.
|
||||
|
||||
"""
|
||||
# Using '*sender' rather than 'sender=None' allows 'sender' to be
|
||||
# used as a keyword argument- i.e. it's an invisible name in the
|
||||
# function signature.
|
||||
if len(sender) == 0:
|
||||
sender = None
|
||||
elif len(sender) > 1:
|
||||
raise TypeError('send() accepts only one positional argument, '
|
||||
'%s given' % len(sender))
|
||||
else:
|
||||
sender = sender[0]
|
||||
if not self.receivers:
|
||||
return []
|
||||
else:
|
||||
return [(receiver, receiver(sender, **kwargs))
|
||||
for receiver in self.receivers_for(sender)]
|
||||
|
||||
def has_receivers_for(self, sender):
|
||||
"""True if there is probably a receiver for *sender*.
|
||||
|
||||
Performs an optimistic check only. Does not guarantee that all
|
||||
weakly referenced receivers are still alive. See
|
||||
:meth:`receivers_for` for a stronger search.
|
||||
|
||||
"""
|
||||
if not self.receivers:
|
||||
return False
|
||||
if self._by_sender[ANY_ID]:
|
||||
return True
|
||||
if sender is ANY:
|
||||
return False
|
||||
return hashable_identity(sender) in self._by_sender
|
||||
|
||||
def receivers_for(self, sender):
|
||||
"""Iterate all live receivers listening for *sender*."""
|
||||
# TODO: test receivers_for(ANY)
|
||||
if self.receivers:
|
||||
sender_id = hashable_identity(sender)
|
||||
if sender_id in self._by_sender:
|
||||
ids = (self._by_sender[ANY_ID] |
|
||||
self._by_sender[sender_id])
|
||||
else:
|
||||
ids = self._by_sender[ANY_ID].copy()
|
||||
for receiver_id in ids:
|
||||
receiver = self.receivers.get(receiver_id)
|
||||
if receiver is None:
|
||||
continue
|
||||
if isinstance(receiver, WeakTypes):
|
||||
strong = receiver()
|
||||
if strong is None:
|
||||
self._disconnect(receiver_id, ANY_ID)
|
||||
continue
|
||||
receiver = strong
|
||||
yield receiver
|
||||
|
||||
def disconnect(self, receiver, sender=ANY):
|
||||
"""Disconnect *receiver* from this signal's events.
|
||||
|
||||
:param receiver: a previously :meth:`connected<connect>` callable
|
||||
|
||||
:param sender: a specific sender to disconnect from, or :obj:`ANY`
|
||||
to disconnect from all senders. Defaults to ``ANY``.
|
||||
|
||||
"""
|
||||
if sender is ANY:
|
||||
sender_id = ANY_ID
|
||||
else:
|
||||
sender_id = hashable_identity(sender)
|
||||
receiver_id = hashable_identity(receiver)
|
||||
self._disconnect(receiver_id, sender_id)
|
||||
|
||||
if ('receiver_disconnected' in self.__dict__ and
|
||||
self.receiver_disconnected.receivers):
|
||||
self.receiver_disconnected.send(self,
|
||||
receiver=receiver,
|
||||
sender=sender)
|
||||
|
||||
def _disconnect(self, receiver_id, sender_id):
|
||||
if sender_id == ANY_ID:
|
||||
if self._by_receiver.pop(receiver_id, False):
|
||||
for bucket in self._by_sender.values():
|
||||
bucket.discard(receiver_id)
|
||||
self.receivers.pop(receiver_id, None)
|
||||
else:
|
||||
self._by_sender[sender_id].discard(receiver_id)
|
||||
|
||||
def _cleanup_receiver(self, receiver_ref):
|
||||
"""Disconnect a receiver from all senders."""
|
||||
self._disconnect(receiver_ref.receiver_id, ANY_ID)
|
||||
|
||||
def _cleanup_sender(self, sender_ref):
|
||||
"""Disconnect all receivers from a sender."""
|
||||
sender_id = sender_ref.sender_id
|
||||
assert sender_id != ANY_ID
|
||||
self._weak_senders.pop(sender_id, None)
|
||||
for receiver_id in self._by_sender.pop(sender_id, ()):
|
||||
self._by_receiver[receiver_id].discard(sender_id)
|
||||
|
||||
def _clear_state(self):
|
||||
"""Throw away all signal state. Useful for unit tests."""
|
||||
self._weak_senders.clear()
|
||||
self.receivers.clear()
|
||||
self._by_sender.clear()
|
||||
self._by_receiver.clear()
|
||||
|
||||
|
||||
receiver_connected = Signal("""\
|
||||
Sent by a :class:`Signal` after a receiver connects.
|
||||
|
||||
:argument: the Signal that was connected to
|
||||
:keyword receiver_arg: the connected receiver
|
||||
:keyword sender_arg: the sender to connect to
|
||||
:keyword weak_arg: true if the connection to receiver_arg is a weak reference
|
||||
|
||||
.. deprecated:: 1.2
|
||||
|
||||
As of 1.2, individual signals have their own private
|
||||
:attr:`~Signal.receiver_connected` and
|
||||
:attr:`~Signal.receiver_disconnected` signals with a slightly simplified
|
||||
call signature. This global signal is planned to be removed in 1.6.
|
||||
|
||||
""")
|
||||
|
||||
|
||||
class NamedSignal(Signal):
|
||||
"""A named generic notification emitter."""
|
||||
|
||||
def __init__(self, name, doc=None):
|
||||
Signal.__init__(self, doc)
|
||||
|
||||
#: The name of this signal.
|
||||
self.name = name
|
||||
|
||||
def __repr__(self):
|
||||
base = Signal.__repr__(self)
|
||||
return "%s; %r>" % (base[:-1], self.name)
|
||||
|
||||
|
||||
class Namespace(dict):
|
||||
"""A mapping of signal names to signals."""
|
||||
|
||||
def signal(self, name, doc=None):
|
||||
"""Return the :class:`NamedSignal` *name*, creating it if required.
|
||||
|
||||
Repeated calls to this function will return the same signal object.
|
||||
|
||||
"""
|
||||
try:
|
||||
return self[name]
|
||||
except KeyError:
|
||||
return self.setdefault(name, NamedSignal(name, doc))
|
||||
|
||||
|
||||
class WeakNamespace(WeakValueDictionary):
|
||||
"""A weak mapping of signal names to signals.
|
||||
|
||||
Automatically cleans up unused Signals when the last reference goes out
|
||||
of scope. This namespace implementation exists for a measure of legacy
|
||||
compatibility with Blinker <= 1.2, and may be dropped in the future.
|
||||
|
||||
"""
|
||||
|
||||
def signal(self, name, doc=None):
|
||||
"""Return the :class:`NamedSignal` *name*, creating it if required.
|
||||
|
||||
Repeated calls to this function will return the same signal object.
|
||||
|
||||
"""
|
||||
try:
|
||||
return self[name]
|
||||
except KeyError:
|
||||
return self.setdefault(name, NamedSignal(name, doc))
|
||||
|
||||
|
||||
signal = Namespace().signal
|
||||
Reference in New Issue
Block a user