Catalyst::Plugin::Continuation - Catalyst Continuation Plugin

    # Make sure to load session plugins too!
    package MyApp;
    use Catalyst qw/Session Session::Store::File
      Session::State::Cookie Continuation/;

    # Create a controller
    package MyApp::Controller::Test;
    use base 'Catalyst::Controller';

    # Add a action with attached action class
    sub counter : Global {
        my ( $self, $c ) = @_;
        my $up      = $c->continue('up');
        my $down    = $c->continue('down');
        my $counter = $c->stash->{counter} || 0;
        $c->res->body(<<"EOF");
    Counter: $counter<br/>
    <a href="$up">++</a>
    <a href="$down">--</a>
    EOF
    }

    # Add private actions for continuations
    sub up   : Private { $_[1]->stash->{counter}++ }
    sub down : Private { $_[1]->stash->{counter}-- }

Catalyst Continuation Plugin.

These methods are overridden to allow the special continuation dispatch.

Contains the continuation object that was restored.

These are internal methods which you can override.

They default to storing inside $c->session, and using generate_session_id in Catalyst::Plugin::Session.

If you want your continuations to be garbage collected in some way you need to override this to store the data in some other backend.

Note that active_continuations returns a hash reference which you can edit. Be careful.

This handler is called when the continuation with the ID $id tried to get invoked but did not exist

Resume a continuation based on an ID or an object.

This is a convenience method intended on saving you the need to load and execute the continuation yourself.

Returns the Catalyst::Continuation object for given method.

Takes the same arguments as forward in Catalyst and it's relatives.

A pseudo-cc - a continuation to your caller.

Note that this does NOT honor the call stack in any way - it is ONLY to reinvoke the immediate caller. See the NeedsLogin test controller in the test suite for an example of how to use this effectively.

Returns the string Catalyst::Continuation by default. You may override this to replace the continuation class.

Continuations take up space, and are by default stored in the session.

When invoked a session will delete itself by default, but anything else will leak, until the session expires.

If this is a concern for you, override the get_continuation family of functions to have a better scheme for storage.

Some approaches you could implement, depending on how you use continuations:

size limiting

Store up to $x continuations, and toss out old ones once this starts to overflow. This is essentially an LRU policy.

continuation grouping

Group all the continuations saved in a single request together. When one of them is deleted, all the rest go with it.

use the fine grained session expiry feature

Catalyst::Plugin::Session allows you to expire some session keys before the entire session expired. You can associate each session with it's own unique key, and avoid extending the continuation's time-to-live.

If you override all these functions then you don't need the Catalyst::Plugin::Session dependency.

Catalyst, Seaside (http://www.seaside.st/), Jifty, Coro::Cont, psychiatrist(1).

Sebastian Riedel, sri@oook.de Yuval Kogman, nothingmuch@woobling.org

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