POE::API::Hooks - Implement lightweight hooks into POE
use POE; use POE::API::Hooks; POE::API::Hooks->add( before_event_dispatch => \&do_something, after_event_dispatch => \&do_something, before_session_create => \&do_something, after_session_create => \&do_something, before_event_enqueue => \&do_something, after_event_enqueue => \&do_something, ); # ... carry on with life as normal ...
This module adds lightweight hooks into the inner workings of POE. Currently, one can add hooks into POE that get called before/after an event is dispatched, before/after a Session is created, and/or before/after an event is enqueued. These callbacks receive the exact same argument list as their Kernel/Session counterpart. For event dispatch related callbacks, see
_data_ev_enqueue in POE::Kernel. For session related callbacks, see
create in POE::Session.
This interface is designed for advanced users. Wrapping any of the available POE internals is a potentially dangerous operation. Please read the POE documentation and source code carefully before attempting an override of this nature.
POE::API::Hooks->add( before_event_dispatch => \&do_something, after_event_dispatch => \&do_something, before_session_create => \&do_something, after_session_create => \&do_something, before_event_enqueue => \&do_something, after_event_enqueue => \&do_something, );
add is the only public method of this class. The method installs the requested hooks. The list of options above contains all possible hooks. No hook is required so the user may set only one hook if they desire.
The callback provided for each hook will be called, obviously, when that state occurs.
before_event_dispatch will be called just before event dispatch, for instance. These callbacks are passed whatever arguments are provided to the wrapped subroutine. For instance, if a
before_session_create callback is registered and a user calls
POE::Session->create('POE'), the registered callback will receive
('POE::Session', 'POE') in
$_[KERNEL]->call($_[SESSION], "event") is used, _event_dispatch is bypassed. This is an optimization, not a bug, but it will cause the event_dispatch hook to be bypassed under this condition. Someone relying on the event_dispatch hook may call this a bug.
Matt Cashner (firstname.lastname@example.org)
Copyright (c) 2004, 2008 Matt Cashner. All rights reserved.
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