def __init__(self, callable_, argsInfo, onDead=None):
'''Use callable_ as a listener of topicName. The argsInfo is the
return value from a Validator, ie an instance of callables.CallArgsInfo.
If given, the onDead will be called with self as parameter, if/when
callable_ gets garbage collected (callable_ is held only by weak
reference). '''
# set call policies
self.acceptsAllKwargs = argsInfo.acceptsAllKwargs
self._autoTopicArgName = argsInfo.autoTopicArgName
self._callable = weakmethod.getWeakRef(callable_, self.__notifyOnDead)
self.__onDead = onDead
# save identity now in case callable dies:
name, mod = getID(callable_) #
self.__nameID = name
self.__module = mod
self.__id = str(id(callable_))[-4:] # only last four digits of id
self.__hash = hash(callable_)
def __init__(self, callable_, argsInfo, onDead=None):
'''Use callable_ as a listener of topicName. The argsInfo is the
return value from a Validator, ie an instance of callables.CallArgsInfo.
If given, the onDead will be called with self as parameter, if/when
callable_ gets garbage collected (callable_ is held only by weak
reference). '''
# set call policies
self.acceptsAllKwargs = argsInfo.acceptsAllKwargs
self._autoTopicArgName = argsInfo.autoTopicArgName
self._callable = weakmethod.getWeakRef(callable_, self.__notifyOnDead)
self.__onDead = onDead
# save identity now in case callable dies:
name, mod = getID(callable_) #
self.__nameID = name
self.__module = mod
self.__id = str(id(callable_))[-4:] # only last four digits of id
self.__hash = hash(callable_)
def getOrCreateTopic(self, name, protoListener=None):
'''Get the topic object for topic of given name, creating it
(and any of its missing parent topics) as necessary. This should
be useful mostly to TopicManager itself.
Topic creation: The topic definition will be obtained
from the first registered TopicDefnProvider (see addTopicDefnProvider()
method) that can provide it. If none is found, then protoListener,
if given, will be used to extract the specification for the topic
message arguments.
So the topic object returned will be either
1. an existing one
2. a new one whose specification was obtained from a TopicDefnProvider
3. a new one whose specification was inferred from protoListener
4. a new one without any specification
For the first three cases, the Topic is ready for sending messages.
In the last case, topic.isSendable() is false and the specification
will be set by the first call to subscribe() (unless you call
topicObj.setMsgArgSpec() first to set it yourself).
Note that if the topic gets created, missing intervening parents
will be created with an empty specification. For instance, if topic
A exists, and name="A.B.C", then A.B will also be created. It will
only be complete (sendable) if a topic definition provider had
its definition.
Note also that if protoListener given, and topic already defined,
the method does not check whether protoListener adheres to the
specification.'''
obj = self.getTopic(name, okIfNone=True)
if obj:
# if object is not sendable but a proto listener was given,
# update its specification so that it is sendable
if (protoListener is not None) and not obj.isSendable():
allArgsDocs, required = topicArgsFromCallable(protoListener)
obj.setMsgArgSpec(allArgsDocs, required)
return obj
# create missing parents
nameTuple = tupleize(name)
parentObj = self.__createParentTopics(nameTuple)
# now the final topic object, args from listener if provided
desc, specGiven = self.__defnProvider.getDefn(nameTuple)
# POLICY: protoListener is used only if no definition available
if specGiven is None:
if protoListener is None:
desc = 'UNDOCUMENTED: created without spec'
else:
allArgsDocs, required = topicArgsFromCallable(protoListener)
specGiven = ArgSpecGiven(allArgsDocs, required)
desc = 'UNDOCUMENTED: created from protoListener "%s" in module %s' % getID(protoListener)
return self.__createTopic(nameTuple, desc, parent = parentObj, specGiven = specGiven)
