NAME

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

SYNOPSIS

    use POE;
    use POE::Component::IKC::Channel;

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

DESCRIPTION

You will never use an IKC Channel directly. They are created by POE::Component::IKC::Server and POE::Component::IKC::Client as needed.

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.

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".
"protocol": Which IKC negociation protocol to use. The original protocol ("IKC") was synchronous and slow. The new protocol ("IKC0") sends all information at once. IKC0 will degrade gracefully to IKC, if the client and server don't match.
Default currently IKC but will move to IKC0 when I'm confident in the new protocol.

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.

EXPORTED FUNCTIONS

create_ikc_channel

Deprecated.

BUGS

AUTHOR

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

COPYRIGHT AND LICENSE

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>