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POE::Component::IKC::Channel.3pm

NAME

POE::Component::IKC::Channel - POE Inter-Kernel Communication I/O session

SYNOPSIS

     use POE;
     use POE::Component::IKC::Channel;
     create_ikc_channel($handle, $name, $on_connect, $subscribe, 
                 $rname, $unix);
 
 

DESCRIPTION

This module implements an POE IKC I/O. When a new connection is established, "IKC::Server" and "IKC::Client" create an "IKC::Channel" to handle the I/O.

IKC communication happens in 2 phases : negociation phase and normal phase.

The negociation phase uses "Filter::Line" and is used to exchange various parameters between kernels (example : kernel names, what type of freeze/thaw to use, etc). After negociation, "IKC::Channel" switches to a "Filter::Reference" and creates a "IKC::Responder", if needed. After this, the channel forwards reads and writes between "Wheel::ReadWrite" and the Responder.

"IKC::Channel" is also in charge of cleaning up kernel names when the foreign kernel disconnects.

EXPORTED FUNCTIONS

create_ikc_channel

This function initiates all the work of connecting to a IKC connection channel. It is a wrapper around "spawn".

METHODS

spawn

     POE::Component::IKC::Channel->spawn(%param);
 
 

Creates a new IKC channel to handle the negociations then the actual data.

Parameters are keyed as follows:

handle

The perl handle we should hand to "Wheel::ReadWrite::new".

kernel_name

The name of the local kernel. This is a stop-gap until event naming has been resolved.

on_connect

Code ref that is called when the negociation phase has terminated. Normaly, you would use this to start the sessions that post events to foreign kernels.

subscribe

Array ref of specifiers (either foreign sessions, or foreign states) that you want to subscribe to. $on_connect will only be called if you can subscribe to all those specifiers. If it can't, it will die().

unix

A flag indicating that the handle is a Unix domain socket or not.

aliases

Arrayref of aliases for the local kernel.

serializers

Arrayref or scalar of the packages that you want to use for data serialization. A serializer package requires 2 functions : freeze (or nfreeze) and thaw. See "POE::Component::IKC::Client".

EVENTS

shutdown

This event causes the server to close it's socket and skiddadle on down the road. Normally it is only posted from IKC::Responder.

If you want to post this event yourself, you can get the channel's session ID from IKC::Client's on_connect:

     POE::Component::IKC::Client->spawn(
         ....
             on_connect=>sub {
                 $heap->{channel} = $poe_kernel->get_active_session()->ID;
             },
         ....
         );
 
 

Then, when it becomes time to disconnect:

     $poe_kernel->call($heap->{channel} => 'shutdown');
 
 

Yes, this is a hack. A cleaner machanism needs to be provided.

BUGS

AUTHOR

Philip Gwyn, <perl-ikc at pied.nu>

COPYRIGHT AND LICENSE

Copyright 1999-2008 by Philip Gwyn. All rights reserved.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

See <http://www.perl.com/language/misc/Artistic.html>

SEE ALSO

POE, POE::Component::IKC::Server, POE::Component::IKC::Client, POE::Component::IKC::Responder