twisted.spread.pb.RemoteCache(RemoteCopy, Serializable) class documentation

Part of twisted.spread.pb (View In Hierarchy)

Known subclasses: twisted.spread.publish.RemotePublished, twisted.spread.test.test_pb.NewStyleCacheCopy, twisted.spread.test.test_pb.RatherBaroqueCache, twisted.spread.test.test_pb.SimpleLocalCache

A cache is a local representation of a remote Cacheable object.

This represents the last known state of this object. It may also have methods invoked on it -- in order to update caches, the cached class generates a pb.RemoteReference to this object as it is originally sent.

Much like copy, I will be invoked with no arguments. Do not implement a constructor that requires arguments in one of my subclasses.

Method remoteMessageReceived A remote message has been received. Dispatch it appropriately.
Method jellyFor serialize me (only for the broker I'm for) as the original cached reference
Method unjellyFor Perform the inverse operation of Jellyable.jellyFor.
Method __cmp__ Compare me [to another RemoteCache.
Method __hash__ Hash me.
Method __del__ Do distributed reference counting on finalize.
Method _borgify Create a new object that shares its state (i.e. its __dict__) and type with this object, but does not share its identity.

Inherited from RemoteCopy:

Method setCopyableState I will be invoked with the state to copy locally.

Inherited from Unjellyable (via RemoteCopy):

Method setStateFor Undocumented

Inherited from Serializable:

Method processUniqueID Return an ID which uniquely represents this object for this process.

Inherited from Jellyable (via Serializable):

Method getStateFor Undocumented
def remoteMessageReceived(self, broker, message, args, kw):

A remote message has been received. Dispatch it appropriately.

The default implementation is to dispatch to a method called 'observe_messagename' and call it on my with the same arguments.

def jellyFor(self, jellier):
from twisted.spread.interfaces.IJellyable
overrides twisted.spread.jelly.Jellyable.jellyFor

serialize me (only for the broker I'm for) as the original cached reference

def unjellyFor(self, unjellier, jellyList):
from twisted.spread.interfaces.IUnjellyable
overrides twisted.spread.pb.RemoteCopy.unjellyFor

Perform the inverse operation of Jellyable.jellyFor.

See Alsotwisted.spread.interfaces.IUnjellyable.unjellyFor
def __cmp__(self, other):

Compare me [to another RemoteCache.

def __hash__(self):

Hash me.

def __del__(self):

Do distributed reference counting on finalize.

def _borgify(self):

Create a new object that shares its state (i.e. its __dict__) and type with this object, but does not share its identity.

This is an instance of the Borg design pattern originally described by Alex Martelli, but unlike the example given there, this is not a replacement for a Singleton. Instead, it is for lifecycle tracking (and distributed garbage collection). The purpose of these separate objects is to have a separate object tracking each application-level reference to the root RemoteCache object being tracked by the broker, and to have their __del__ methods be invoked.

This may be achievable via a weak value dictionary to track the root RemoteCache instances instead, but this implementation strategy predates the availability of weak references in Python.

ReturnsThe new instance. (type: self.__class__)
API Documentation for twisted, generated by pydoctor at 2020-03-25 17:34:30.