Hub#
- class glue.core.hub.Hub(*args)[source]#
Bases:
object
The hub manages communication between subscribers.
Objects
subscribe()
to receive specific message types. When a message is passed tobroadcast()
, the hub observes the following protocol:For each subscriber, it looks for a message class subscription that is a parent class of the input message type (if several are found, the most-subclassed one is chosen)
If one is found, it calls the subscriptions filter(message) class (if provided)
If filter(message) == True, it calls handler(message) (or notify(message) if handler wasn’t provided).
Any arguments that are passed to Hub will be registered to the new hub object.
Methods Summary
broadcast
(message)Broadcasts a message to all subscribed objects.
get_handler
(subscriber, message)ignore_callbacks
(ignore_type)is_subscribed
(subscriber, message)Test whether the subscriber has subscribed to a given message class
subscribe
(subscriber, message_class[, ...])Subscribe an object to a type of message class.
unsubscribe
(subscriber, message)Remove a (subscriber,message) pair from subscription list.
unsubscribe_all
(subscriber)Unsubscribe the object from any subscriptions.
Methods Documentation
- broadcast(message)[source]#
Broadcasts a message to all subscribed objects.
- Parameters:
message (
Message
) – The message to broadcast
- is_subscribed(subscriber, message)[source]#
Test whether the subscriber has subscribed to a given message class
- Parameters:
subscriber – The subscriber to test
message – The message class to test
Returns:
True if the subscriber/message pair have been subscribed to the hub
- subscribe(subscriber, message_class, handler=None, filter=<function Hub.<lambda>>)[source]#
Subscribe an object to a type of message class.
- Parameters:
subscriber (
HubListener
) – The subscribing objectmessage_class – A
Message
class to subscribe tohandler – An optional function of the form handler(message) that will receive the message on behalf of the subscriber. If not provided, this defaults to the HubListener’s notify method
filter – An optional function of the form filter(message). Messages are only passed to the subscriber if filter(message) == True. The default is to always pass messages.
- Raises:
InvalidMessage: If the input class isn’t a
Message
classInvalidSubscriber: If the input subscriber isn’t a HubListener object.