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- from __future__ import absolute_import
- from pydispatch import dispatcher
- from scrapy.utils import signal as _signal
-
-
- class SignalManager(object):
-
- def __init__(self, sender=dispatcher.Anonymous):
- self.sender = sender
-
- def connect(self, receiver, signal, **kwargs):
- """
- Connect a receiver function to a signal.
-
- The signal can be any object, although Scrapy comes with some
- predefined signals that are documented in the :ref:`topics-signals`
- section.
-
- :param receiver: the function to be connected
- :type receiver: callable
-
- :param signal: the signal to connect to
- :type signal: object
- """
- kwargs.setdefault('sender', self.sender)
- return dispatcher.connect(receiver, signal, **kwargs)
-
- def disconnect(self, receiver, signal, **kwargs):
- """
- Disconnect a receiver function from a signal. This has the
- opposite effect of the :meth:`connect` method, and the arguments
- are the same.
- """
- kwargs.setdefault('sender', self.sender)
- return dispatcher.disconnect(receiver, signal, **kwargs)
-
- def send_catch_log(self, signal, **kwargs):
- """
- Send a signal, catch exceptions and log them.
-
- The keyword arguments are passed to the signal handlers (connected
- through the :meth:`connect` method).
- """
- kwargs.setdefault('sender', self.sender)
- return _signal.send_catch_log(signal, **kwargs)
-
- def send_catch_log_deferred(self, signal, **kwargs):
- """
- Like :meth:`send_catch_log` but supports returning `deferreds`_ from
- signal handlers.
-
- Returns a Deferred that gets fired once all signal handlers
- deferreds were fired. Send a signal, catch exceptions and log them.
-
- The keyword arguments are passed to the signal handlers (connected
- through the :meth:`connect` method).
-
- .. _deferreds: https://twistedmatrix.com/documents/current/core/howto/defer.html
- """
- kwargs.setdefault('sender', self.sender)
- return _signal.send_catch_log_deferred(signal, **kwargs)
-
- def disconnect_all(self, signal, **kwargs):
- """
- Disconnect all receivers from the given signal.
-
- :param signal: the signal to disconnect from
- :type signal: object
- """
- kwargs.setdefault('sender', self.sender)
- return _signal.disconnect_all(signal, **kwargs)
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