NAME
    CGI::Application::Plugin::Forward - Pass control from one run mode to
    another

VERSION
    Version 1.06

SYNOPSIS
        use base 'CGI::Application';
        use CGI::Application::Plugin::Forward;

        sub setup {
            my $self = shift;
            $self->run_modes([qw(
                start
                second_runmode
            )]);
        }
        sub start {
            my $self = shift;
            return $self->forward('second_runmode');
        }
        sub second_runmode {
            my $self = shift;

            my $rm = $self->get_current_runmode;  # 'second_runmode'

        }

DESCRIPTION
    The forward method passes control to another run mode and returns its
    output. This is equivalent to calling "$self->$other_runmode", except
    that CGI::Application's internal value of the current run mode is
    updated.

    This means that calling "$self->get_current_runmode" after calling
    "forward" will return the name of the new run mode. This is useful for
    modules that depend on the name of the current run mode such as
    CGI::Application::Plugin::AnyTemplate.

    For example, here's how to pass control to a run mode named
    "other_action" from "start" while updating the value of
    "current_run_mode":

        sub setup {
            my $self = shift;
            $self->run_modes({
                start         => 'start',
                other_action  => 'other_method',
            });
        }
        sub start {
            my $self = shift;
            return $self->forward('other_action');
        }
        sub other_method {
            my $self = shift;

            my $rm = $self->get_current_runmode;  # 'other_action'
        }

    Note that forward accepts the *name* of the run mode (in this case
    *'other_action'*), which might not be the same as the name of the method
    that handles the run mode (in this case *'other_method'*)

    You can still call "$self->other_method" directly, but
    "current_run_mode" will not be updated:

        sub setup {
            my $self = shift;
            $self->run_modes({
                start         => 'start',
                other_action  => 'other_method',
            });
        }
        sub start {
            my $self = shift;
            return $self->other_method;
        }
        sub other_method {
            my $self = shift;

            my $rm = $self->get_current_runmode;  # 'start'
        }

    Forward will work with coderef-based runmodes as well:

        sub setup {
            my $self = shift;
            $self->run_modes({
                start         => 'start',
                anon_action   => sub {
                    my $self = shift;
                    my $rm = $self->get_current_runmode;  # 'anon_action'
                },
            });
        }
        sub start {
            my $self = shift;
            return $self->forward('anon_action');
        }

FORWARD vs. REDIRECT
    Calling "forward" changes the run mode of your application, but it stays
    within the same HTTP request.

    To redirect to a new runmode using a completely new web request, you
    might consider using the "redirect" method provided by
    CGI::Application::Plugin::Redirect.

    The advantage of using an external redirect as opposed to an internal
    forward is that it provides a 'clean break' between pages.

    For instance, in a typical BREAD application (Browse, Read, Edit, Add,
    Delete), after the user completes an action, you usually return the user
    to the Browse list. For instance, when the user adds a new record via a
    POST form, and your app returns them to the list of records.

    If you use "forward", then you are still in the same request as the
    original *add record*. The user might hit *reload*, expecting to refresh
    the list of records. But in fact, *reload* will attempt to repost the
    *add record* form. The user's browser might present a warning about
    reposting the same data. The browser may refuse to redisplay the page,
    due for caching reasons.

    So in this case, it may make more sense to do a fresh HTTP redirect back
    to the Browse list.

METHODS
  forward
    Runs another run mode passing any parameters you supply. Returns the
    output of the new run mode.

        return $self->forward('run_mode_name', @run_mode_params);

HOOKS
    Before the forwarded run mode is called, the "forward_prerun" hook is
    called. You can use this hook to do any prep work that you want to do
    before any new run mode gains control.

    This is similar to CGI::Application's built in "cgiapp_prerun" method,
    but it is called each time you call forward; not just the when your
    application starts.

        sub setup {
            my $self = shift;
            $self->add_callback('forward_prerun' => \&prepare_rm_stuff);
        }

        sub prepare_rm_stuff {
            my $self = shift;
            # do any necessary prep work here....
        }

    Note that your hooked method will only be called when you call forward.
    If you never call "forward", the hook will not be called. In particuar,
    the hook will not be called for your application's "start_mode". For
    that, you still use "cgiapp_prerun".

    If you want to have a method run for every run mode *including* the
    "start_mode", then you can call the hook directly from "cgiapp_prerun".

        sub setup {
            my $self = shift;
            $self->add_callback('forward_prerun' => \&prepare_rm_stuff);
        }
        sub cgiapp_prerun {
            my $self = shift;
            $self->prepare_rm_stuff;
        }

        sub prepare_rm_stuff {
            my $self = shift;
            # do any necessary prep work here....
        }

    Alternately, you can hook "cgiapp_prerun" to the "forward_prerun" hook:

        sub setup {
            my $self = shift;
            $self->add_callback('forward_prerun' => \&cgiapp_prerun);
        }
        sub cgiapp_prerun {
            my $self = shift;
            # do any necessary prep work here....
        }

    This is a less flexible solution, since certain things that can be done
    in "cgiapp_prerun" (like setting "prerun_mode") won't work when the
    method is called from the "forward_prerun" hook.

AUTHOR
    Michael Graham, "<mag-perl@occamstoothbrush.com>"

BUGS
    Please report any bugs or feature requests to
    "bug-cgi-application-plugin-forward@rt.cpan.org", or through the web
    interface at <http://rt.cpan.org>. I will be notified, and then you'll
    automatically be notified of progress on your bug as I make changes.

ACKNOWLEDGEMENTS
    Thanks to Mark Stosberg for the idea and...well...the implementation as
    well.

COPYRIGHT & LICENSE
    Copyright 2005 Michael Graham, All Rights Reserved.

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