Phly_PubSub: Publish-Subscribe framework for PHP
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Phly_PubSub is a simple, flexible Publish-Subscribe framework for PHP,
based on Dojo's dojo.publish/dojo.subscribe system.
With Phly_PubSub, you may register any callback to listen on any topic,
as well as publish notifications to any topic from any location. As an
example:
// Create logger and subscribe to 'log' topic
$log = new Zend_Log(new Zend_Log_Writer_Stream('/tmp/app.log'));
Phly_PubSub::subscribe('log', $log, 'info');
// Within some application code:
Phly_PubSub::publish('log', 'Log message');
Phly_PubSub can therefore be used:
* to ensure a separation of concerns
* as a minimal Aspect-Oriented Programming (AOP) mechanism for PHP
* to provide an opt-in subject/observer mechanism for your code without
requiring refactoring
TODO/Further Questions
======================
* Exception handling. Should exceptions raised by subscribers prevent
execution of other subscribers and/or the calling code?
* If not, how should errors be handled/aggregated/reported?
* Should return values from subscribers be allowed? If so, how would they be
handled?
* Use case would be to allow early escape from a method based on the return
value of a subscriber
