| 1 | |
| 2 | #--------------------------------------------------------------------------- |
| 3 | """ |
| 4 | This module provides a publish-subscribe component that allows |
| 5 | listeners to subcribe to messages of a given topic. Contrary to the |
| 6 | original wxPython.lib.pubsub module (which it is based on), it uses |
| 7 | weak referencing to the subscribers so the lifetime of subscribers |
| 8 | is not affected by Publisher. Also, callable objects can be used in |
| 9 | addition to functions and bound methods. See Publisher class docs for |
| 10 | more details. |
| 11 | |
| 12 | Thanks to Robb Shecter and Robin Dunn for having provided |
| 13 | the basis for this module (which now shares most of the concepts but |
| 14 | very little design or implementation with the original |
| 15 | wxPython.lib.pubsub). |
| 16 | |
| 17 | The publisher is a singleton instance of the PublisherClass class. You |
| 18 | access the instance via the Publisher object available from the module:: |
| 19 | |
| 20 | from wx.lib.pubsub import Publisher |
| 21 | Publisher().subscribe(...) |
| 22 | Publisher().sendMessage(...) |
| 23 | ... |
| 24 | |
| 25 | :Author: Oliver Schoenborn |
| 26 | :Since: Apr 2004 |
| 27 | :Version: $Id$ |
| 28 | :Copyright: \(c) 2004 Oliver Schoenborn |
| 29 | :License: wxWidgets |
| 30 | """ |
| 31 | |
| 32 | _implNotes = """ |
| 33 | Implementation notes |
| 34 | -------------------- |
| 35 | |
| 36 | In class Publisher, I represent the topics-listener set as a tree |
| 37 | where each node is a topic, and contains a list of listeners of that |
| 38 | topic, and a dictionary of subtopics of that topic. When the Publisher |
| 39 | is told to send a message for a given topic, it traverses the tree |
| 40 | down to the topic for which a message is being generated, all |
| 41 | listeners on the way get sent the message. |
| 42 | |
| 43 | Publisher currently uses a weak listener topic tree to store the |
| 44 | topics for each listener, and if a listener dies before being |
| 45 | unsubscribed, the tree is notified, and the tree eliminates the |
| 46 | listener from itself. |
| 47 | |
| 48 | Ideally, _TopicTreeNode would be a generic _TreeNode with named |
| 49 | subnodes, and _TopicTreeRoot would be a generic _Tree with named |
| 50 | nodes, and Publisher would store listeners in each node and a topic |
| 51 | tuple would be converted to a path in the tree. This would lead to a |
| 52 | much cleaner separation of concerns. But time is over, time to move on. |
| 53 | """ |
| 54 | #--------------------------------------------------------------------------- |
| 55 | |
| 56 | # for function and method parameter counting: |
| 57 | from types import InstanceType |
| 58 | from inspect import getargspec, ismethod, isfunction |
| 59 | # for weakly bound methods: |
| 60 | from new import instancemethod as InstanceMethod |
| 61 | from weakref import ref as WeakRef |
| 62 | |
| 63 | # ----------------------------------------------------------------------------- |
| 64 | |
| 65 | def _isbound(method): |
| 66 | """Return true if method is a bound method, false otherwise""" |
| 67 | assert ismethod(method) |
| 68 | return method.im_self is not None |
| 69 | |
| 70 | |
| 71 | def _paramMinCountFunc(function): |
| 72 | """Given a function, return pair (min,d) where min is minimum # of |
| 73 | args required, and d is number of default arguments.""" |
| 74 | assert isfunction(function) |
| 75 | (args, va, kwa, dflt) = getargspec(function) |
| 76 | lenDef = len(dflt or ()) |
| 77 | lenArgs = len(args or ()) |
| 78 | lenVA = int(va is not None) |
| 79 | return (lenArgs - lenDef + lenVA, lenDef) |
| 80 | |
| 81 | |
| 82 | def _paramMinCount(callableObject): |
| 83 | """ |
| 84 | Given a callable object (function, method or callable instance), |
| 85 | return pair (min,d) where min is minimum # of args required, and d |
| 86 | is number of default arguments. The 'self' parameter, in the case |
| 87 | of methods, is not counted. |
| 88 | """ |
| 89 | if type(callableObject) is InstanceType: |
| 90 | min, d = _paramMinCountFunc(callableObject.__call__.im_func) |
| 91 | return min-1, d |
| 92 | elif ismethod(callableObject): |
| 93 | min, d = _paramMinCountFunc(callableObject.im_func) |
| 94 | return min-1, d |
| 95 | elif isfunction(callableObject): |
| 96 | return _paramMinCountFunc(callableObject) |
| 97 | else: |
| 98 | raise 'Cannot determine type of callable: '+repr(callableObject) |
| 99 | |
| 100 | |
| 101 | def _tupleize(items): |
| 102 | """Convert items to tuple if not already one, |
| 103 | so items must be a list, tuple or non-sequence""" |
| 104 | if isinstance(items, list): |
| 105 | raise TypeError, 'Not allowed to tuple-ize a list' |
| 106 | elif isinstance(items, (str, unicode)) and items.find('.') != -1: |
| 107 | items = tuple(items.split('.')) |
| 108 | elif not isinstance(items, tuple): |
| 109 | items = (items,) |
| 110 | return items |
| 111 | |
| 112 | |
| 113 | def _getCallableName(callable): |
| 114 | """Get name for a callable, ie function, bound |
| 115 | method or callable instance""" |
| 116 | if ismethod(callable): |
| 117 | return '%s.%s ' % (callable.im_self, callable.im_func.func_name) |
| 118 | elif isfunction(callable): |
| 119 | return '%s ' % callable.__name__ |
| 120 | else: |
| 121 | return '%s ' % callable |
| 122 | |
| 123 | |
| 124 | def _removeItem(item, fromList): |
| 125 | """Attempt to remove item from fromList, return true |
| 126 | if successful, false otherwise.""" |
| 127 | try: |
| 128 | fromList.remove(item) |
| 129 | return True |
| 130 | except ValueError: |
| 131 | return False |
| 132 | |
| 133 | |
| 134 | # ----------------------------------------------------------------------------- |
| 135 | |
| 136 | class _WeakMethod: |
| 137 | """Represent a weak bound method, i.e. a method doesn't keep alive the |
| 138 | object that it is bound to. It uses WeakRef which, used on its own, |
| 139 | produces weak methods that are dead on creation, not very useful. |
| 140 | Typically, you will use the getRef() function instead of using |
| 141 | this class directly. """ |
| 142 | |
| 143 | def __init__(self, method, notifyDead = None): |
| 144 | """The method must be bound. notifyDead will be called when |
| 145 | object that method is bound to dies. """ |
| 146 | assert ismethod(method) |
| 147 | if method.im_self is None: |
| 148 | raise ValueError, "We need a bound method!" |
| 149 | if notifyDead is None: |
| 150 | self.objRef = WeakRef(method.im_self) |
| 151 | else: |
| 152 | self.objRef = WeakRef(method.im_self, notifyDead) |
| 153 | self.fun = method.im_func |
| 154 | self.cls = method.im_class |
| 155 | |
| 156 | def __call__(self): |
| 157 | """Returns a new.instancemethod if object for method still alive. |
| 158 | Otherwise return None. Note that instancemethod causes a |
| 159 | strong reference to object to be created, so shouldn't save |
| 160 | the return value of this call. Note also that this __call__ |
| 161 | is required only for compatibility with WeakRef.ref(), otherwise |
| 162 | there would be more efficient ways of providing this functionality.""" |
| 163 | if self.objRef() is None: |
| 164 | return None |
| 165 | else: |
| 166 | return InstanceMethod(self.fun, self.objRef(), self.cls) |
| 167 | |
| 168 | def __eq__(self, method2): |
| 169 | """Two WeakMethod objects compare equal if they refer to the same method |
| 170 | of the same instance. Thanks to Josiah Carlson for patch and clarifications |
| 171 | on how dict uses eq/cmp and hashing. """ |
| 172 | if not isinstance(method2, _WeakMethod): |
| 173 | return False |
| 174 | return self.fun is method2.fun \ |
| 175 | and self.objRef() is method2.objRef() \ |
| 176 | and self.objRef() is not None |
| 177 | |
| 178 | def __hash__(self): |
| 179 | """Hash is an optimization for dict searches, it need not |
| 180 | return different numbers for every different object. Some objects |
| 181 | are not hashable (eg objects of classes derived from dict) so no |
| 182 | hash(objRef()) in there, and hash(self.cls) would only be useful |
| 183 | in the rare case where instance method was rebound. """ |
| 184 | return hash(self.fun) |
| 185 | |
| 186 | def __repr__(self): |
| 187 | dead = '' |
| 188 | if self.objRef() is None: |
| 189 | dead = '; DEAD' |
| 190 | obj = '<%s at %s%s>' % (self.__class__, id(self), dead) |
| 191 | return obj |
| 192 | |
| 193 | def refs(self, weakRef): |
| 194 | """Return true if we are storing same object referred to by weakRef.""" |
| 195 | return self.objRef == weakRef |
| 196 | |
| 197 | |
| 198 | def _getWeakRef(obj, notifyDead=None): |
| 199 | """Get a weak reference to obj. If obj is a bound method, a _WeakMethod |
| 200 | object, that behaves like a WeakRef, is returned, if it is |
| 201 | anything else a WeakRef is returned. If obj is an unbound method, |
| 202 | a ValueError will be raised.""" |
| 203 | if ismethod(obj): |
| 204 | createRef = _WeakMethod |
| 205 | else: |
| 206 | createRef = WeakRef |
| 207 | |
| 208 | if notifyDead is None: |
| 209 | return createRef(obj) |
| 210 | else: |
| 211 | return createRef(obj, notifyDead) |
| 212 | |
| 213 | |
| 214 | # ----------------------------------------------------------------------------- |
| 215 | |
| 216 | def getStrAllTopics(): |
| 217 | """Function to call if, for whatever reason, you need to know |
| 218 | explicitely what is the string to use to indicate 'all topics'.""" |
| 219 | return '' |
| 220 | |
| 221 | |
| 222 | # alias, easier to see where used |
| 223 | ALL_TOPICS = getStrAllTopics() |
| 224 | |
| 225 | # ----------------------------------------------------------------------------- |
| 226 | |
| 227 | |
| 228 | class _NodeCallback: |
| 229 | """Encapsulate a weak reference to a method of a TopicTreeNode |
| 230 | in such a way that the method can be called, if the node is |
| 231 | still alive, but the callback does not *keep* the node alive. |
| 232 | Also, define two methods, preNotify() and noNotify(), which can |
| 233 | be redefined to something else, very useful for testing. |
| 234 | """ |
| 235 | |
| 236 | def __init__(self, obj): |
| 237 | self.objRef = _getWeakRef(obj) |
| 238 | |
| 239 | def __call__(self, weakCB): |
| 240 | notify = self.objRef() |
| 241 | if notify is not None: |
| 242 | self.preNotify(weakCB) |
| 243 | notify(weakCB) |
| 244 | else: |
| 245 | self.noNotify() |
| 246 | |
| 247 | def preNotify(self, dead): |
| 248 | """'Gets called just before our callback (self.objRef) is called""" |
| 249 | pass |
| 250 | |
| 251 | def noNotify(self): |
| 252 | """Gets called if the TopicTreeNode for this callback is dead""" |
| 253 | pass |
| 254 | |
| 255 | |
| 256 | class _TopicTreeNode: |
| 257 | """A node in the topic tree. This contains a list of callables |
| 258 | that are interested in the topic that this node is associated |
| 259 | with, and contains a dictionary of subtopics, whose associated |
| 260 | values are other _TopicTreeNodes. The topic of a node is not stored |
| 261 | in the node, so that the tree can be implemented as a dictionary |
| 262 | rather than a list, for ease of use (and, likely, performance). |
| 263 | |
| 264 | Note that it uses _NodeCallback to encapsulate a callback for |
| 265 | when a registered listener dies, possible thanks to WeakRef. |
| 266 | Whenever this callback is called, the onDeadListener() function, |
| 267 | passed in at construction time, is called (unless it is None). |
| 268 | """ |
| 269 | |
| 270 | def __init__(self, topicPath, onDeadListenerWeakCB): |
| 271 | self.__subtopics = {} |
| 272 | self.__callables = [] |
| 273 | self.__topicPath = topicPath |
| 274 | self.__onDeadListenerWeakCB = onDeadListenerWeakCB |
| 275 | |
| 276 | def getPathname(self): |
| 277 | """The complete node path to us, ie., the topic tuple that would lead to us""" |
| 278 | return self.__topicPath |
| 279 | |
| 280 | def createSubtopic(self, subtopic, topicPath): |
| 281 | """Create a child node for subtopic""" |
| 282 | return self.__subtopics.setdefault(subtopic, |
| 283 | _TopicTreeNode(topicPath, self.__onDeadListenerWeakCB)) |
| 284 | |
| 285 | def hasSubtopic(self, subtopic): |
| 286 | """Return true only if topic string is one of subtopics of this node""" |
| 287 | return self.__subtopics.has_key(subtopic) |
| 288 | |
| 289 | def getNode(self, subtopic): |
| 290 | """Return ref to node associated with subtopic""" |
| 291 | return self.__subtopics[subtopic] |
| 292 | |
| 293 | def addCallable(self, callable): |
| 294 | """Add a callable to list of callables for this topic node""" |
| 295 | try: |
| 296 | id = self.__callables.index(_getWeakRef(callable)) |
| 297 | return self.__callables[id] |
| 298 | except ValueError: |
| 299 | wrCall = _getWeakRef(callable, _NodeCallback(self.__notifyDead)) |
| 300 | self.__callables.append(wrCall) |
| 301 | return wrCall |
| 302 | |
| 303 | def getCallables(self): |
| 304 | """Get callables associated with this topic node""" |
| 305 | return [cb() for cb in self.__callables if cb() is not None] |
| 306 | |
| 307 | def hasCallable(self, callable): |
| 308 | """Return true if callable in this node""" |
| 309 | try: |
| 310 | self.__callables.index(_getWeakRef(callable)) |
| 311 | return True |
| 312 | except ValueError: |
| 313 | return False |
| 314 | |
| 315 | def sendMessage(self, message): |
| 316 | """Send a message to our callables""" |
| 317 | deliveryCount = 0 |
| 318 | for cb in self.__callables: |
| 319 | listener = cb() |
| 320 | if listener is not None: |
| 321 | listener(message) |
| 322 | deliveryCount += 1 |
| 323 | return deliveryCount |
| 324 | |
| 325 | def removeCallable(self, callable): |
| 326 | """Remove weak callable from our node (and return True). |
| 327 | Does nothing if not here (and returns False).""" |
| 328 | try: |
| 329 | self.__callables.remove(_getWeakRef(callable)) |
| 330 | return True |
| 331 | except ValueError: |
| 332 | return False |
| 333 | |
| 334 | def clearCallables(self): |
| 335 | """Abandon list of callables to caller. We no longer have |
| 336 | any callables after this method is called.""" |
| 337 | tmpList = [cb for cb in self.__callables if cb() is not None] |
| 338 | self.__callables = [] |
| 339 | return tmpList |
| 340 | |
| 341 | def __notifyDead(self, dead): |
| 342 | """Gets called when a listener dies, thanks to WeakRef""" |
| 343 | #print 'TreeNODE', `self`, 'received death certificate for ', dead |
| 344 | self.__cleanupDead() |
| 345 | if self.__onDeadListenerWeakCB is not None: |
| 346 | cb = self.__onDeadListenerWeakCB() |
| 347 | if cb is not None: |
| 348 | cb(dead) |
| 349 | |
| 350 | def __cleanupDead(self): |
| 351 | """Remove all dead objects from list of callables""" |
| 352 | self.__callables = [cb for cb in self.__callables if cb() is not None] |
| 353 | |
| 354 | def __str__(self): |
| 355 | """Print us in a not-so-friendly, but readable way, good for debugging.""" |
| 356 | strVal = [] |
| 357 | for callable in self.getCallables(): |
| 358 | strVal.append(_getCallableName(callable)) |
| 359 | for topic, node in self.__subtopics.iteritems(): |
| 360 | strVal.append(' (%s: %s)' %(topic, node)) |
| 361 | return ''.join(strVal) |
| 362 | |
| 363 | |
| 364 | class _TopicTreeRoot(_TopicTreeNode): |
| 365 | """ |
| 366 | The root of the tree knows how to access other node of the |
| 367 | tree and is the gateway of the tree user to the tree nodes. |
| 368 | It can create topics, and and remove callbacks, etc. |
| 369 | |
| 370 | For efficiency, it stores a dictionary of listener-topics, |
| 371 | so that unsubscribing a listener just requires finding the |
| 372 | topics associated to a listener, and finding the corresponding |
| 373 | nodes of the tree. Without it, unsubscribing would require |
| 374 | that we search the whole tree for all nodes that contain |
| 375 | given listener. Since Publisher is a singleton, it will |
| 376 | contain all topics in the system so it is likely to be a large |
| 377 | tree. However, it is possible that in some runs, unsubscribe() |
| 378 | is called very little by the user, in which case most unsubscriptions |
| 379 | are automatic, ie caused by the listeners dying. In this case, |
| 380 | a flag is set to indicate that the dictionary should be cleaned up |
| 381 | at the next opportunity. This is not necessary, it is just an |
| 382 | optimization. |
| 383 | """ |
| 384 | |
| 385 | def __init__(self): |
| 386 | self.__callbackDict = {} |
| 387 | self.__callbackDictCleanup = 0 |
| 388 | # all child nodes will call our __rootNotifyDead method |
| 389 | # when one of their registered listeners dies |
| 390 | _TopicTreeNode.__init__(self, (ALL_TOPICS,), |
| 391 | _getWeakRef(self.__rootNotifyDead)) |
| 392 | |
| 393 | def addTopic(self, topic, listener): |
| 394 | """Add topic to tree if doesnt exist, and add listener to topic node""" |
| 395 | assert isinstance(topic, tuple) |
| 396 | topicNode = self.__getTreeNode(topic, make=True) |
| 397 | weakCB = topicNode.addCallable(listener) |
| 398 | assert topicNode.hasCallable(listener) |
| 399 | |
| 400 | theList = self.__callbackDict.setdefault(weakCB, []) |
| 401 | assert self.__callbackDict.has_key(weakCB) |
| 402 | # add it only if we don't already have it |
| 403 | try: |
| 404 | weakTopicNode = WeakRef(topicNode) |
| 405 | theList.index(weakTopicNode) |
| 406 | except ValueError: |
| 407 | theList.append(weakTopicNode) |
| 408 | assert self.__callbackDict[weakCB].index(weakTopicNode) >= 0 |
| 409 | |
| 410 | def getTopics(self, listener): |
| 411 | """Return the list of topics for given listener""" |
| 412 | weakNodes = self.__callbackDict.get(_getWeakRef(listener), []) |
| 413 | return [weakNode().getPathname() for weakNode in weakNodes |
| 414 | if weakNode() is not None] |
| 415 | |
| 416 | def isSubscribed(self, listener, topic=None): |
| 417 | """Return true if listener is registered for topic specified. |
| 418 | If no topic specified, return true if subscribed to something. |
| 419 | Use topic=getStrAllTopics() to determine if a listener will receive |
| 420 | messages for all topics.""" |
| 421 | weakCB = _getWeakRef(listener) |
| 422 | if topic is None: |
| 423 | return self.__callbackDict.has_key(weakCB) |
| 424 | else: |
| 425 | topicPath = _tupleize(topic) |
| 426 | for weakNode in self.__callbackDict[weakCB]: |
| 427 | if topicPath == weakNode().getPathname(): |
| 428 | return True |
| 429 | return False |
| 430 | |
| 431 | def unsubscribe(self, listener, topicList): |
| 432 | """Remove listener from given list of topics. If topicList |
| 433 | doesn't have any topics for which listener has subscribed, |
| 434 | nothing happens.""" |
| 435 | weakCB = _getWeakRef(listener) |
| 436 | if not self.__callbackDict.has_key(weakCB): |
| 437 | return |
| 438 | |
| 439 | cbNodes = self.__callbackDict[weakCB] |
| 440 | if topicList is None: |
| 441 | for weakNode in cbNodes: |
| 442 | weakNode().removeCallable(listener) |
| 443 | del self.__callbackDict[weakCB] |
| 444 | return |
| 445 | |
| 446 | for weakNode in cbNodes: |
| 447 | node = weakNode() |
| 448 | if node is not None and node.getPathname() in topicList: |
| 449 | success = node.removeCallable(listener) |
| 450 | assert success == True |
| 451 | cbNodes.remove(weakNode) |
| 452 | assert not self.isSubscribed(listener, node.getPathname()) |
| 453 | |
| 454 | def unsubAll(self, topicList, onNoSuchTopic): |
| 455 | """Unsubscribe all listeners registered for any topic in |
| 456 | topicList. If a topic in the list does not exist, and |
| 457 | onNoSuchTopic is not None, a call |
| 458 | to onNoSuchTopic(topic) is done for that topic.""" |
| 459 | for topic in topicList: |
| 460 | node = self.__getTreeNode(topic) |
| 461 | if node is not None: |
| 462 | weakCallables = node.clearCallables() |
| 463 | for callable in weakCallables: |
| 464 | weakNodes = self.__callbackDict[callable] |
| 465 | success = _removeItem(WeakRef(node), weakNodes) |
| 466 | assert success == True |
| 467 | if weakNodes == []: |
| 468 | del self.__callbackDict[callable] |
| 469 | elif onNoSuchTopic is not None: |
| 470 | onNoSuchTopic(topic) |
| 471 | |
| 472 | def sendMessage(self, topic, message, onTopicNeverCreated): |
| 473 | """Send a message for given topic to all registered listeners. If |
| 474 | topic doesn't exist, call onTopicNeverCreated(topic).""" |
| 475 | # send to the all-toipcs listeners |
| 476 | deliveryCount = _TopicTreeNode.sendMessage(self, message) |
| 477 | # send to those who listen to given topic or any of its supertopics |
| 478 | node = self |
| 479 | for topicItem in topic: |
| 480 | assert topicItem != '' |
| 481 | if node.hasSubtopic(topicItem): |
| 482 | node = node.getNode(topicItem) |
| 483 | deliveryCount += node.sendMessage(message) |
| 484 | else: # topic never created, don't bother continuing |
| 485 | if onTopicNeverCreated is not None: |
| 486 | onTopicNeverCreated(topic) |
| 487 | break |
| 488 | return deliveryCount |
| 489 | |
| 490 | def numListeners(self): |
| 491 | """Return a pair (live, dead) with count of live and dead listeners in tree""" |
| 492 | dead, live = 0, 0 |
| 493 | for cb in self.__callbackDict: |
| 494 | if cb() is None: |
| 495 | dead += 1 |
| 496 | else: |
| 497 | live += 1 |
| 498 | return live, dead |
| 499 | |
| 500 | # clean up the callback dictionary after how many dead listeners |
| 501 | callbackDeadLimit = 10 |
| 502 | |
| 503 | def __rootNotifyDead(self, dead): |
| 504 | #print 'TreeROOT received death certificate for ', dead |
| 505 | self.__callbackDictCleanup += 1 |
| 506 | if self.__callbackDictCleanup > _TopicTreeRoot.callbackDeadLimit: |
| 507 | self.__callbackDictCleanup = 0 |
| 508 | oldDict = self.__callbackDict |
| 509 | self.__callbackDict = {} |
| 510 | for weakCB, weakNodes in oldDict.iteritems(): |
| 511 | if weakCB() is not None: |
| 512 | self.__callbackDict[weakCB] = weakNodes |
| 513 | |
| 514 | def __getTreeNode(self, topic, make=False): |
| 515 | """Return the tree node for 'topic' from the topic tree. If it |
| 516 | doesnt exist and make=True, create it first.""" |
| 517 | # if the all-topics, give root; |
| 518 | if topic == (ALL_TOPICS,): |
| 519 | return self |
| 520 | |
| 521 | # not root, so traverse tree |
| 522 | node = self |
| 523 | path = () |
| 524 | for topicItem in topic: |
| 525 | path += (topicItem,) |
| 526 | if topicItem == ALL_TOPICS: |
| 527 | raise ValueError, 'Topic tuple must not contain ""' |
| 528 | if make: |
| 529 | node = node.createSubtopic(topicItem, path) |
| 530 | elif node.hasSubtopic(topicItem): |
| 531 | node = node.getNode(topicItem) |
| 532 | else: |
| 533 | return None |
| 534 | # done |
| 535 | return node |
| 536 | |
| 537 | def printCallbacks(self): |
| 538 | strVal = ['Callbacks:\n'] |
| 539 | for listener, weakTopicNodes in self.__callbackDict.iteritems(): |
| 540 | topics = [topic() for topic in weakTopicNodes if topic() is not None] |
| 541 | strVal.append(' %s: %s\n' % (_getCallableName(listener()), topics)) |
| 542 | return ''.join(strVal) |
| 543 | |
| 544 | def __str__(self): |
| 545 | return 'all: %s' % _TopicTreeNode.__str__(self) |
| 546 | |
| 547 | |
| 548 | # ----------------------------------------------------------------------------- |
| 549 | |
| 550 | class _SingletonKey: pass |
| 551 | |
| 552 | class PublisherClass: |
| 553 | """ |
| 554 | The publish/subscribe manager. It keeps track of which listeners |
| 555 | are interested in which topics (see subscribe()), and sends a |
| 556 | Message for a given topic to listeners that have subscribed to |
| 557 | that topic, with optional user data (see sendMessage()). |
| 558 | |
| 559 | The three important concepts for Publisher are: |
| 560 | |
| 561 | - listener: a function, bound method or |
| 562 | callable object that can be called with one parameter |
| 563 | (not counting 'self' in the case of methods). The parameter |
| 564 | will be a reference to a Message object. E.g., these listeners |
| 565 | are ok:: |
| 566 | |
| 567 | class Foo: |
| 568 | def __call__(self, a, b=1): pass # can be called with only one arg |
| 569 | def meth(self, a): pass # takes only one arg |
| 570 | def meth2(self, a=2, b=''): pass # can be called with one arg |
| 571 | |
| 572 | def func(a, b=''): pass |
| 573 | |
| 574 | Foo foo |
| 575 | Publisher().subscribe(foo) # functor |
| 576 | Publisher().subscribe(foo.meth) # bound method |
| 577 | Publisher().subscribe(foo.meth2) # bound method |
| 578 | Publisher().subscribe(func) # function |
| 579 | |
| 580 | The three types of callables all have arguments that allow a call |
| 581 | with only one argument. In every case, the parameter 'a' will contain |
| 582 | the message. |
| 583 | |
| 584 | - topic: a single word, a tuple of words, or a string containing a |
| 585 | set of words separated by dots, for example: 'sports.baseball'. |
| 586 | A tuple or a dotted notation string denotes a hierarchy of |
| 587 | topics from most general to least. For example, a listener of |
| 588 | this topic:: |
| 589 | |
| 590 | ('sports','baseball') |
| 591 | |
| 592 | would receive messages for these topics:: |
| 593 | |
| 594 | ('sports', 'baseball') # because same |
| 595 | ('sports', 'baseball', 'highscores') # because more specific |
| 596 | |
| 597 | but not these:: |
| 598 | |
| 599 | 'sports' # because more general |
| 600 | ('sports',) # because more general |
| 601 | () or ('') # because only for those listening to 'all' topics |
| 602 | ('news') # because different topic |
| 603 | |
| 604 | - message: this is an instance of Message, containing the topic for |
| 605 | which the message was sent, and any data the sender specified. |
| 606 | |
| 607 | :note: This class is visible to importers of pubsub only as a |
| 608 | Singleton. I.e., every time you execute 'Publisher()', it's |
| 609 | actually the same instance of PublisherClass that is |
| 610 | returned. So to use, just do'Publisher().method()'. |
| 611 | |
| 612 | """ |
| 613 | |
| 614 | __ALL_TOPICS_TPL = (ALL_TOPICS, ) |
| 615 | |
| 616 | def __init__(self, singletonKey): |
| 617 | """Construct a Publisher. This can only be done by the pubsub |
| 618 | module. You just use pubsub.Publisher().""" |
| 619 | if not isinstance(singletonKey, _SingletonKey): |
| 620 | raise invalid_argument("Use Publisher() to get access to singleton") |
| 621 | self.__messageCount = 0 |
| 622 | self.__deliveryCount = 0 |
| 623 | self.__topicTree = _TopicTreeRoot() |
| 624 | |
| 625 | # |
| 626 | # Public API |
| 627 | # |
| 628 | |
| 629 | def getDeliveryCount(self): |
| 630 | """How many listeners have received a message since beginning of run""" |
| 631 | return self.__deliveryCount |
| 632 | |
| 633 | def getMessageCount(self): |
| 634 | """How many times sendMessage() was called since beginning of run""" |
| 635 | return self.__messageCount |
| 636 | |
| 637 | def subscribe(self, listener, topic = ALL_TOPICS): |
| 638 | """ |
| 639 | Subscribe listener for given topic. If topic is not specified, |
| 640 | listener will be subscribed for all topics (that listener will |
| 641 | receive a Message for any topic for which a message is generated). |
| 642 | |
| 643 | This method may be called multiple times for one listener, |
| 644 | registering it with many topics. It can also be invoked many |
| 645 | times for a particular topic, each time with a different |
| 646 | listener. See the class doc for requirements on listener and |
| 647 | topic. |
| 648 | |
| 649 | :note: The listener is held by Publisher() only by *weak* |
| 650 | reference. This means you must ensure you have at |
| 651 | least one strong reference to listener, otherwise it |
| 652 | will be DOA ("dead on arrival"). This is particularly |
| 653 | easy to forget when wrapping a listener method in a |
| 654 | proxy object (e.g. to bind some of its parameters), |
| 655 | e.g.:: |
| 656 | |
| 657 | class Foo: |
| 658 | def listener(self, event): pass |
| 659 | class Wrapper: |
| 660 | def __init__(self, fun): self.fun = fun |
| 661 | def __call__(self, *args): self.fun(*args) |
| 662 | foo = Foo() |
| 663 | Publisher().subscribe( Wrapper(foo.listener) ) # whoops: DOA! |
| 664 | wrapper = Wrapper(foo.listener) |
| 665 | Publisher().subscribe(wrapper) # good! |
| 666 | |
| 667 | :note: Calling this method for the same listener, with two |
| 668 | topics in the same branch of the topic hierarchy, will |
| 669 | cause the listener to be notified twice when a message |
| 670 | for the deepest topic is sent. E.g. |
| 671 | subscribe(listener, 't1') and then subscribe(listener, |
| 672 | ('t1','t2')) means that when calling sendMessage('t1'), |
| 673 | listener gets one message, but when calling |
| 674 | sendMessage(('t1','t2')), listener gets message twice. |
| 675 | |
| 676 | """ |
| 677 | self.validate(listener) |
| 678 | |
| 679 | if topic is None: |
| 680 | raise TypeError, 'Topic must be either a word, tuple of '\ |
| 681 | 'words, or getStrAllTopics()' |
| 682 | |
| 683 | self.__topicTree.addTopic(_tupleize(topic), listener) |
| 684 | |
| 685 | def isSubscribed(self, listener, topic=None): |
| 686 | """Return true if listener has subscribed to topic specified. |
| 687 | If no topic specified, return true if subscribed to something. |
| 688 | Use topic=getStrAllTopics() to determine if a listener will receive |
| 689 | messages for all topics.""" |
| 690 | return self.__topicTree.isSubscribed(listener, topic) |
| 691 | |
| 692 | def validate(self, listener): |
| 693 | """Similar to isValid(), but raises a TypeError exception if not valid""" |
| 694 | # check callable |
| 695 | if not callable(listener): |
| 696 | raise TypeError, 'Listener '+`listener`+' must be a '\ |
| 697 | 'function, bound method or instance.' |
| 698 | # ok, callable, but if method, is it bound: |
| 699 | elif ismethod(listener) and not _isbound(listener): |
| 700 | raise TypeError, 'Listener '+`listener`+\ |
| 701 | ' is a method but it is unbound!' |
| 702 | |
| 703 | # check that it takes the right number of parameters |
| 704 | min, d = _paramMinCount(listener) |
| 705 | if min > 1: |
| 706 | raise TypeError, 'Listener '+`listener`+" can't"\ |
| 707 | ' require more than one parameter!' |
| 708 | if min <= 0 and d == 0: |
| 709 | raise TypeError, 'Listener '+`listener`+' lacking arguments!' |
| 710 | |
| 711 | assert (min == 0 and d>0) or (min == 1) |
| 712 | |
| 713 | def isValid(self, listener): |
| 714 | """Return true only if listener will be able to subscribe to |
| 715 | Publisher.""" |
| 716 | try: |
| 717 | self.validate(listener) |
| 718 | return True |
| 719 | except TypeError: |
| 720 | return False |
| 721 | |
| 722 | def unsubAll(self, topics=None, onNoSuchTopic=None): |
| 723 | """Unsubscribe all listeners subscribed for topics. Topics can |
| 724 | be a single topic (string or tuple) or a list of topics (ie |
| 725 | list containing strings and/or tuples). If topics is not |
| 726 | specified, all listeners for all topics will be unsubscribed, |
| 727 | ie. the Publisher singleton will have no topics and no listeners |
| 728 | left. If onNoSuchTopic is given, it will be called as |
| 729 | onNoSuchTopic(topic) for each topic that is unknown. |
| 730 | """ |
| 731 | if topics is None: |
| 732 | del self.__topicTree |
| 733 | self.__topicTree = _TopicTreeRoot() |
| 734 | return |
| 735 | |
| 736 | # make sure every topics are in tuple form |
| 737 | if isinstance(topics, list): |
| 738 | topicList = [_tupleize(x) for x in topics] |
| 739 | else: |
| 740 | topicList = [_tupleize(topics)] |
| 741 | |
| 742 | # unsub every listener of topics |
| 743 | self.__topicTree.unsubAll(topicList, onNoSuchTopic) |
| 744 | |
| 745 | def unsubscribe(self, listener, topics=None): |
| 746 | """Unsubscribe listener. If topics not specified, listener is |
| 747 | completely unsubscribed. Otherwise, it is unsubscribed only |
| 748 | for the topic (the usual tuple) or list of topics (ie a list |
| 749 | of tuples) specified. Nothing happens if listener is not actually |
| 750 | subscribed to any of the topics. |
| 751 | |
| 752 | Note that if listener subscribed for two topics (a,b) and (a,c), |
| 753 | then unsubscribing for topic (a) will do nothing. You must |
| 754 | use getAssociatedTopics(listener) and give unsubscribe() the returned |
| 755 | list (or a subset thereof). |
| 756 | """ |
| 757 | self.validate(listener) |
| 758 | topicList = None |
| 759 | if topics is not None: |
| 760 | if isinstance(topics, list): |
| 761 | topicList = [_tupleize(x) for x in topics] |
| 762 | else: |
| 763 | topicList = [_tupleize(topics)] |
| 764 | |
| 765 | self.__topicTree.unsubscribe(listener, topicList) |
| 766 | |
| 767 | def getAssociatedTopics(self, listener): |
| 768 | """Return a list of topics the given listener is registered with. |
| 769 | Returns [] if listener never subscribed. |
| 770 | |
| 771 | :attention: when using the return of this method to compare to |
| 772 | expected list of topics, remember that topics that are |
| 773 | not in the form of a tuple appear as a one-tuple in |
| 774 | the return. E.g. if you have subscribed a listener to |
| 775 | 'topic1' and ('topic2','subtopic2'), this method |
| 776 | returns:: |
| 777 | |
| 778 | associatedTopics = [('topic1',), ('topic2','subtopic2')] |
| 779 | """ |
| 780 | return self.__topicTree.getTopics(listener) |
| 781 | |
| 782 | def sendMessage(self, topic=ALL_TOPICS, data=None, onTopicNeverCreated=None): |
| 783 | """Send a message for given topic, with optional data, to |
| 784 | subscribed listeners. If topic is not specified, only the |
| 785 | listeners that are interested in all topics will receive message. |
| 786 | The onTopicNeverCreated is an optional callback of your choice that |
| 787 | will be called if the topic given was never created (i.e. it, or |
| 788 | one of its subtopics, was never subscribed to by any listener). |
| 789 | It will be called as onTopicNeverCreated(topic).""" |
| 790 | aTopic = _tupleize(topic) |
| 791 | message = Message(aTopic, data) |
| 792 | self.__messageCount += 1 |
| 793 | |
| 794 | # send to those who listen to all topics |
| 795 | self.__deliveryCount += \ |
| 796 | self.__topicTree.sendMessage(aTopic, message, onTopicNeverCreated) |
| 797 | |
| 798 | # |
| 799 | # Private methods |
| 800 | # |
| 801 | |
| 802 | def __call__(self): |
| 803 | """Allows for singleton""" |
| 804 | return self |
| 805 | |
| 806 | def __str__(self): |
| 807 | return str(self.__topicTree) |
| 808 | |
| 809 | # Create the Publisher singleton. We prevent users from (inadvertently) |
| 810 | # instantiating more than one object, by requiring a key that is |
| 811 | # accessible only to module. From |
| 812 | # this point forward any calls to Publisher() will invoke the __call__ |
| 813 | # of this instance which just returns itself. |
| 814 | # |
| 815 | # The only flaw with this approach is that you can't derive a new |
| 816 | # class from Publisher without jumping through hoops. If this ever |
| 817 | # becomes an issue then a new Singleton implementaion will need to be |
| 818 | # employed. |
| 819 | _key = _SingletonKey() |
| 820 | Publisher = PublisherClass(_key) |
| 821 | |
| 822 | |
| 823 | #--------------------------------------------------------------------------- |
| 824 | |
| 825 | class Message: |
| 826 | """ |
| 827 | A simple container object for the two components of a message: the |
| 828 | topic and the user data. An instance of Message is given to your |
| 829 | listener when called by Publisher().sendMessage(topic) (if your |
| 830 | listener callback was registered for that topic). |
| 831 | """ |
| 832 | def __init__(self, topic, data): |
| 833 | self.topic = topic |
| 834 | self.data = data |
| 835 | |
| 836 | def __str__(self): |
| 837 | return '[Topic: '+`self.topic`+', Data: '+`self.data`+']' |
| 838 | |
| 839 | |
| 840 | #--------------------------------------------------------------------------- |
| 841 | |
| 842 | |
| 843 | # |
| 844 | # Code for a simple command-line test |
| 845 | # |
| 846 | def test(): |
| 847 | def done(funcName): |
| 848 | print '----------- Done %s -----------' % funcName |
| 849 | |
| 850 | def testParam(): |
| 851 | def testFunc00(): pass |
| 852 | def testFunc21(a,b,c=1): pass |
| 853 | def testFuncA(*args): pass |
| 854 | def testFuncAK(*args,**kwds): pass |
| 855 | def testFuncK(**kwds): pass |
| 856 | |
| 857 | class Foo: |
| 858 | def testMeth(self,a,b): pass |
| 859 | def __call__(self, a): pass |
| 860 | class Foo2: |
| 861 | def __call__(self, *args): pass |
| 862 | |
| 863 | assert _paramMinCount(testFunc00)==(0,0) |
| 864 | assert _paramMinCount(testFunc21)==(2,1) |
| 865 | assert _paramMinCount(testFuncA) ==(1,0) |
| 866 | assert _paramMinCount(testFuncAK)==(1,0) |
| 867 | assert _paramMinCount(testFuncK) ==(0,0) |
| 868 | foo = Foo() |
| 869 | assert _paramMinCount(Foo.testMeth)==(2,0) |
| 870 | assert _paramMinCount(foo.testMeth)==(2,0) |
| 871 | assert _paramMinCount(foo)==(1,0) |
| 872 | assert _paramMinCount(Foo2())==(1,0) |
| 873 | |
| 874 | done('testParam') |
| 875 | |
| 876 | testParam() |
| 877 | #------------------------ |
| 878 | |
| 879 | _NodeCallback.notified = 0 |
| 880 | def testPreNotifyNode(self, dead): |
| 881 | _NodeCallback.notified += 1 |
| 882 | print 'testPreNotifyNODE heard notification of', `dead` |
| 883 | _NodeCallback.preNotify = testPreNotifyNode |
| 884 | |
| 885 | def testTreeNode(): |
| 886 | |
| 887 | class WS: |
| 888 | def __init__(self, s): |
| 889 | self.s = s |
| 890 | def __call__(self, msg): |
| 891 | print 'WS#', self.s, ' received msg ', msg |
| 892 | def __str__(self): |
| 893 | return self.s |
| 894 | |
| 895 | def testPreNotifyRoot(dead): |
| 896 | print 'testPreNotifyROOT heard notification of', `dead` |
| 897 | |
| 898 | node = _TopicTreeNode((ALL_TOPICS,), WeakRef(testPreNotifyRoot)) |
| 899 | boo, baz, bid = WS('boo'), WS('baz'), WS('bid') |
| 900 | node.addCallable(boo) |
| 901 | node.addCallable(baz) |
| 902 | node.addCallable(boo) |
| 903 | assert node.getCallables() == [boo,baz] |
| 904 | assert node.hasCallable(boo) |
| 905 | |
| 906 | node.removeCallable(bid) # no-op |
| 907 | assert node.hasCallable(baz) |
| 908 | assert node.getCallables() == [boo,baz] |
| 909 | |
| 910 | node.removeCallable(boo) |
| 911 | assert node.getCallables() == [baz] |
| 912 | assert node.hasCallable(baz) |
| 913 | assert not node.hasCallable(boo) |
| 914 | |
| 915 | node.removeCallable(baz) |
| 916 | assert node.getCallables() == [] |
| 917 | assert not node.hasCallable(baz) |
| 918 | |
| 919 | node2 = node.createSubtopic('st1', ('st1',)) |
| 920 | node3 = node.createSubtopic('st2', ('st2',)) |
| 921 | cb1, cb2, cb = WS('st1_cb1'), WS('st1_cb2'), WS('st2_cb') |
| 922 | node2.addCallable(cb1) |
| 923 | node2.addCallable(cb2) |
| 924 | node3.addCallable(cb) |
| 925 | node2.createSubtopic('st3', ('st1','st3')) |
| 926 | node2.createSubtopic('st4', ('st1','st4')) |
| 927 | |
| 928 | print str(node) |
| 929 | assert str(node) == ' (st1: st1_cb1 st1_cb2 (st4: ) (st3: )) (st2: st2_cb )' |
| 930 | |
| 931 | # verify send message, and that a dead listener does not get sent one |
| 932 | delivered = node2.sendMessage('hello') |
| 933 | assert delivered == 2 |
| 934 | del cb1 |
| 935 | delivered = node2.sendMessage('hello') |
| 936 | assert delivered == 1 |
| 937 | assert _NodeCallback.notified == 1 |
| 938 | |
| 939 | done('testTreeNode') |
| 940 | |
| 941 | testTreeNode() |
| 942 | #------------------------ |
| 943 | |
| 944 | def testValidate(): |
| 945 | class Foo: |
| 946 | def __call__(self, a): pass |
| 947 | def fun(self, b): pass |
| 948 | def fun2(self, b=1): pass |
| 949 | def fun3(self, a, b=2): pass |
| 950 | def badFun(self): pass |
| 951 | def badFun2(): pass |
| 952 | def badFun3(self, a, b): pass |
| 953 | |
| 954 | server = Publisher() |
| 955 | foo = Foo() |
| 956 | server.validate(foo) |
| 957 | server.validate(foo.fun) |
| 958 | server.validate(foo.fun2) |
| 959 | server.validate(foo.fun3) |
| 960 | assert not server.isValid(foo.badFun) |
| 961 | assert not server.isValid(foo.badFun2) |
| 962 | assert not server.isValid(foo.badFun3) |
| 963 | |
| 964 | done('testValidate') |
| 965 | |
| 966 | testValidate() |
| 967 | #------------------------ |
| 968 | |
| 969 | class SimpleListener: |
| 970 | def __init__(self, number): |
| 971 | self.number = number |
| 972 | def __call__(self, message = ''): |
| 973 | print 'Callable #%s got the message "%s"' %(self.number, message) |
| 974 | def notify(self, message): |
| 975 | print '%s.notify() got the message "%s"' %(self.number, message) |
| 976 | def __str__(self): |
| 977 | return "SimpleListener_%s" % self.number |
| 978 | |
| 979 | def testSubscribe(): |
| 980 | publisher = Publisher() |
| 981 | |
| 982 | topic1 = 'politics' |
| 983 | topic2 = ('history','middle age') |
| 984 | topic3 = ('politics','UN') |
| 985 | topic4 = ('politics','NATO') |
| 986 | topic5 = ('politics','NATO','US') |
| 987 | |
| 988 | lisnr1 = SimpleListener(1) |
| 989 | lisnr2 = SimpleListener(2) |
| 990 | def func(message, a=1): |
| 991 | print 'Func received message "%s"' % message |
| 992 | lisnr3 = func |
| 993 | lisnr4 = lambda x: 'Lambda received message "%s"' % x |
| 994 | |
| 995 | assert not publisher.isSubscribed(lisnr1) |
| 996 | assert not publisher.isSubscribed(lisnr2) |
| 997 | assert not publisher.isSubscribed(lisnr3) |
| 998 | assert not publisher.isSubscribed(lisnr4) |
| 999 | |
| 1000 | publisher.subscribe(lisnr1, topic1) |
| 1001 | assert publisher.getAssociatedTopics(lisnr1) == [(topic1,)] |
| 1002 | publisher.subscribe(lisnr1, topic2) |
| 1003 | publisher.subscribe(lisnr1, topic1) # do it again, should be no-op |
| 1004 | assert publisher.getAssociatedTopics(lisnr1) == [(topic1,),topic2] |
| 1005 | publisher.subscribe(lisnr2.notify, topic3) |
| 1006 | assert publisher.getAssociatedTopics(lisnr2.notify) == [topic3] |
| 1007 | assert publisher.getAssociatedTopics(lisnr1) == [(topic1,),topic2] |
| 1008 | publisher.subscribe(lisnr3, topic5) |
| 1009 | assert publisher.getAssociatedTopics(lisnr3) == [topic5] |
| 1010 | assert publisher.getAssociatedTopics(lisnr2.notify) == [topic3] |
| 1011 | assert publisher.getAssociatedTopics(lisnr1) == [(topic1,),topic2] |
| 1012 | publisher.subscribe(lisnr4) |
| 1013 | |
| 1014 | print "Publisher tree: ", publisher |
| 1015 | assert publisher.isSubscribed(lisnr1) |
| 1016 | assert publisher.isSubscribed(lisnr1, topic1) |
| 1017 | assert publisher.isSubscribed(lisnr1, topic2) |
| 1018 | assert publisher.isSubscribed(lisnr2.notify) |
| 1019 | assert publisher.isSubscribed(lisnr3, topic5) |
| 1020 | assert publisher.isSubscribed(lisnr4, ALL_TOPICS) |
| 1021 | expectTopicTree = 'all: <lambda> (politics: SimpleListener_1 (UN: SimpleListener_2.notify ) (NATO: (US: func ))) (history: (middle age: SimpleListener_1 ))' |
| 1022 | print "Publisher tree: ", publisher |
| 1023 | assert str(publisher) == expectTopicTree |
| 1024 | |
| 1025 | publisher.unsubscribe(lisnr1, 'booboo') # should do nothing |
| 1026 | assert publisher.getAssociatedTopics(lisnr1) == [(topic1,),topic2] |
| 1027 | assert publisher.getAssociatedTopics(lisnr2.notify) == [topic3] |
| 1028 | assert publisher.getAssociatedTopics(lisnr3) == [topic5] |
| 1029 | publisher.unsubscribe(lisnr1, topic1) |
| 1030 | assert publisher.getAssociatedTopics(lisnr1) == [topic2] |
| 1031 | assert publisher.getAssociatedTopics(lisnr2.notify) == [topic3] |
| 1032 | assert publisher.getAssociatedTopics(lisnr3) == [topic5] |
| 1033 | publisher.unsubscribe(lisnr1, topic2) |
| 1034 | publisher.unsubscribe(lisnr1, topic2) |
| 1035 | publisher.unsubscribe(lisnr2.notify, topic3) |
| 1036 | publisher.unsubscribe(lisnr3, topic5) |
| 1037 | assert publisher.getAssociatedTopics(lisnr1) == [] |
| 1038 | assert publisher.getAssociatedTopics(lisnr2.notify) == [] |
| 1039 | assert publisher.getAssociatedTopics(lisnr3) == [] |
| 1040 | publisher.unsubscribe(lisnr4) |
| 1041 | |
| 1042 | expectTopicTree = 'all: (politics: (UN: ) (NATO: (US: ))) (history: (middle age: ))' |
| 1043 | print "Publisher tree: ", publisher |
| 1044 | assert str(publisher) == expectTopicTree |
| 1045 | assert publisher.getDeliveryCount() == 0 |
| 1046 | assert publisher.getMessageCount() == 0 |
| 1047 | |
| 1048 | publisher.unsubAll() |
| 1049 | assert str(publisher) == 'all: ' |
| 1050 | |
| 1051 | done('testSubscribe') |
| 1052 | |
| 1053 | testSubscribe() |
| 1054 | #------------------------ |
| 1055 | |
| 1056 | def testUnsubAll(): |
| 1057 | publisher = Publisher() |
| 1058 | |
| 1059 | topic1 = 'politics' |
| 1060 | topic2 = ('history','middle age') |
| 1061 | topic3 = ('politics','UN') |
| 1062 | topic4 = ('politics','NATO') |
| 1063 | topic5 = ('politics','NATO','US') |
| 1064 | |
| 1065 | lisnr1 = SimpleListener(1) |
| 1066 | lisnr2 = SimpleListener(2) |
| 1067 | def func(message, a=1): |
| 1068 | print 'Func received message "%s"' % message |
| 1069 | lisnr3 = func |
| 1070 | lisnr4 = lambda x: 'Lambda received message "%s"' % x |
| 1071 | |
| 1072 | publisher.subscribe(lisnr1, topic1) |
| 1073 | publisher.subscribe(lisnr1, topic2) |
| 1074 | publisher.subscribe(lisnr2.notify, topic3) |
| 1075 | publisher.subscribe(lisnr3, topic2) |
| 1076 | publisher.subscribe(lisnr3, topic5) |
| 1077 | publisher.subscribe(lisnr4) |
| 1078 | |
| 1079 | expectTopicTree = 'all: <lambda> (politics: SimpleListener_1 (UN: SimpleListener_2.notify ) (NATO: (US: func ))) (history: (middle age: SimpleListener_1 func ))' |
| 1080 | print "Publisher tree: ", publisher |
| 1081 | assert str(publisher) == expectTopicTree |
| 1082 | |
| 1083 | publisher.unsubAll(topic1) |
| 1084 | assert publisher.getAssociatedTopics(lisnr1) == [topic2] |
| 1085 | assert not publisher.isSubscribed(lisnr1, topic1) |
| 1086 | |
| 1087 | publisher.unsubAll(topic2) |
| 1088 | print publisher |
| 1089 | assert publisher.getAssociatedTopics(lisnr1) == [] |
| 1090 | assert publisher.getAssociatedTopics(lisnr3) == [topic5] |
| 1091 | assert not publisher.isSubscribed(lisnr1) |
| 1092 | assert publisher.isSubscribed(lisnr3, topic5) |
| 1093 | |
| 1094 | #print "Publisher tree: ", publisher |
| 1095 | expectTopicTree = 'all: <lambda> (politics: (UN: SimpleListener_2.notify ) (NATO: (US: func ))) (history: (middle age: ))' |
| 1096 | assert str(publisher) == expectTopicTree |
| 1097 | publisher.unsubAll(ALL_TOPICS) |
| 1098 | #print "Publisher tree: ", publisher |
| 1099 | expectTopicTree = 'all: (politics: (UN: SimpleListener_2.notify ) (NATO: (US: func ))) (history: (middle age: ))' |
| 1100 | assert str(publisher) == expectTopicTree |
| 1101 | |
| 1102 | publisher.unsubAll() |
| 1103 | done('testUnsubAll') |
| 1104 | |
| 1105 | testUnsubAll() |
| 1106 | #------------------------ |
| 1107 | |
| 1108 | def testSend(): |
| 1109 | publisher = Publisher() |
| 1110 | called = [] |
| 1111 | |
| 1112 | class TestListener: |
| 1113 | def __init__(self, num): |
| 1114 | self.number = num |
| 1115 | def __call__(self, b): |
| 1116 | called.append( 'TL%scb' % self.number ) |
| 1117 | def notify(self, b): |
| 1118 | called.append( 'TL%sm' % self.number ) |
| 1119 | def funcListener(b): |
| 1120 | called.append('func') |
| 1121 | |
| 1122 | lisnr1 = TestListener(1) |
| 1123 | lisnr2 = TestListener(2) |
| 1124 | lisnr3 = funcListener |
| 1125 | lisnr4 = lambda x: called.append('lambda') |
| 1126 | |
| 1127 | topic1 = 'politics' |
| 1128 | topic2 = 'history' |
| 1129 | topic3 = ('politics','UN') |
| 1130 | topic4 = ('politics','NATO','US') |
| 1131 | topic5 = ('politics','NATO') |
| 1132 | |
| 1133 | publisher.subscribe(lisnr1, topic1) |
| 1134 | publisher.subscribe(lisnr2, topic2) |
| 1135 | publisher.subscribe(lisnr2.notify, topic2) |
| 1136 | publisher.subscribe(lisnr3, topic4) |
| 1137 | publisher.subscribe(lisnr4) |
| 1138 | |
| 1139 | print publisher |
| 1140 | |
| 1141 | # setup ok, now test send/receipt |
| 1142 | publisher.sendMessage(topic1) |
| 1143 | assert called == ['lambda','TL1cb'] |
| 1144 | called = [] |
| 1145 | publisher.sendMessage(topic2) |
| 1146 | assert called == ['lambda','TL2cb','TL2m'] |
| 1147 | called = [] |
| 1148 | publisher.sendMessage(topic3) |
| 1149 | assert called == ['lambda','TL1cb'] |
| 1150 | called = [] |
| 1151 | publisher.sendMessage(topic4) |
| 1152 | assert called == ['lambda','TL1cb','func'] |
| 1153 | called = [] |
| 1154 | publisher.sendMessage(topic5) |
| 1155 | assert called == ['lambda','TL1cb'] |
| 1156 | assert publisher.getDeliveryCount() == 12 |
| 1157 | assert publisher.getMessageCount() == 5 |
| 1158 | |
| 1159 | # test weak referencing works: |
| 1160 | _NodeCallback.notified = 0 |
| 1161 | del lisnr2 |
| 1162 | called = [] |
| 1163 | publisher.sendMessage(topic2) |
| 1164 | assert called == ['lambda'] |
| 1165 | assert _NodeCallback.notified == 2 |
| 1166 | |
| 1167 | done('testSend') |
| 1168 | |
| 1169 | testSend() |
| 1170 | assert _NodeCallback.notified == 5 |
| 1171 | |
| 1172 | def testDead(): |
| 1173 | # verify if weak references work as expected |
| 1174 | print '------ Starting testDead ----------' |
| 1175 | node = _TopicTreeNode('t1', None) |
| 1176 | lisnr1 = SimpleListener(1) |
| 1177 | lisnr2 = SimpleListener(2) |
| 1178 | lisnr3 = SimpleListener(3) |
| 1179 | lisnr4 = SimpleListener(4) |
| 1180 | |
| 1181 | node.addCallable(lisnr1) |
| 1182 | node.addCallable(lisnr2) |
| 1183 | node.addCallable(lisnr3) |
| 1184 | node.addCallable(lisnr4) |
| 1185 | |
| 1186 | print 'Deleting listeners first' |
| 1187 | _NodeCallback.notified = 0 |
| 1188 | del lisnr1 |
| 1189 | del lisnr2 |
| 1190 | assert _NodeCallback.notified == 2 |
| 1191 | |
| 1192 | print 'Deleting node first' |
| 1193 | _NodeCallback.notified = 0 |
| 1194 | del node |
| 1195 | del lisnr3 |
| 1196 | del lisnr4 |
| 1197 | assert _NodeCallback.notified == 0 |
| 1198 | |
| 1199 | lisnr1 = SimpleListener(1) |
| 1200 | lisnr2 = SimpleListener(2) |
| 1201 | lisnr3 = SimpleListener(3) |
| 1202 | lisnr4 = SimpleListener(4) |
| 1203 | |
| 1204 | # try same with root of tree |
| 1205 | node = _TopicTreeRoot() |
| 1206 | node.addTopic(('',), lisnr1) |
| 1207 | node.addTopic(('',), lisnr2) |
| 1208 | node.addTopic(('',), lisnr3) |
| 1209 | node.addTopic(('',), lisnr4) |
| 1210 | # add objects that will die immediately to see if cleanup occurs |
| 1211 | # this must be done visually as it is a low-level detail |
| 1212 | _NodeCallback.notified = 0 |
| 1213 | _TopicTreeRoot.callbackDeadLimit = 3 |
| 1214 | node.addTopic(('',), SimpleListener(5)) |
| 1215 | node.addTopic(('',), SimpleListener(6)) |
| 1216 | node.addTopic(('',), SimpleListener(7)) |
| 1217 | print node.numListeners() |
| 1218 | assert node.numListeners() == (4, 3) |
| 1219 | node.addTopic(('',), SimpleListener(8)) |
| 1220 | assert node.numListeners() == (4, 0) |
| 1221 | assert _NodeCallback.notified == 4 |
| 1222 | |
| 1223 | print 'Deleting listeners first' |
| 1224 | _NodeCallback.notified = 0 |
| 1225 | del lisnr1 |
| 1226 | del lisnr2 |
| 1227 | assert _NodeCallback.notified == 2 |
| 1228 | print 'Deleting node first' |
| 1229 | _NodeCallback.notified = 0 |
| 1230 | del node |
| 1231 | del lisnr3 |
| 1232 | del lisnr4 |
| 1233 | assert _NodeCallback.notified == 0 |
| 1234 | |
| 1235 | done('testDead') |
| 1236 | |
| 1237 | testDead() |
| 1238 | |
| 1239 | print 'Exiting tests' |
| 1240 | #--------------------------------------------------------------------------- |
| 1241 | |
| 1242 | if __name__ == '__main__': |
| 1243 | test() |