CGI::Application::Plugin::AnyTemplate::Driver::TemplateToolkit - Template::Toolkit plugin to AnyTemplate

Introduction
Multiple Applications in a Shared Persistent Environment
Disabling TT Object Caching
TT Object Caching and Include Paths

CONFIGURATION

required_modules

DRIVER METHODS
SEE ALSO
ACKNOWLEDGEMENTS
AUTHOR
COPYRIGHT & LICENSE

NAME

CGI::Application::Plugin::AnyTemplate::Driver::TemplateToolkit - Template::Toolkit plugin to AnyTemplate

DESCRIPTION

This is a driver for the CGI::Application::Plugin::AnyTemplate manpage, which provides the implementation details specific to rendering templates via the Template::Toolkit templating system.

All AnyTemplate drivers are designed to be used the same way. For general usage instructions, see the documentation of the CGI::Application::Plugin::AnyTemplate manpage.

EMBEDDED COMPONENT SYNTAX (Template::Toolkit)

The Template::Toolkit syntax for embedding components is:

    [% CGIAPP.embed("some_run_mode", param1, param2, 'literal string3') %]

This can be overridden by the following configuration variables:

    embed_tag_name       # default 'CGIAPP'

For instance by setting the following values in your configuration file:

    embed_tag_name       'MYAPP'

Then the embedded component tag will look like:

    [% MYAPP.embed("some_run_mode") %]

TT OBJECT CACHING (singleton support)

Introduction

In a persistent environment, rather than creating a Template::Toolkit object each time you fill a template, it is much more efficient to load a single Template::Toolkit object and use this object to render all of your templates.

However, in a persistent environment, you may have several different applications running, and they all might need to set different Template::Toolkit options (such as POST_CHOMP, etc.).

By default, when the TemplateToolkit driver creates a Template::Toolkit object, it caches it. From that point on, whenever the same application needs a Template::Toolkit object, the driver uses the cached object rather than creating a new one.

Multiple Applications in a Shared Persistent Environment

An attempt is made to prevent different applications from sharing the same TT object.

Internally, the TT objects are stored in a private hash keyed by the web application's class name.

You can explicitly specify the class name when you call config:

        $self->template->config(
            type          => 'TemplateToolkit',
            TemplateToolkit => {
                storage_class => 'My::Project',
            },
        );

If you don't specify the class name, then the package containing the subroutine that called config is used. For instance:

    package My::Project;
    sub setup {
        my $self = shift;
        $self->template->config(                 # My::Project is used to store
            type          => 'TemplateToolkit',  # cached TT object
        );
    }

A typical CGI::Application module hierarchy looks like this:

    CGI::Application
        My::Project
            My::Webapp

In this hierarchy, it makes sense to store the cached TT object in My::Project. To make this happen, either call $self->template->config from within My::Project, or explicitly name the storage_class when you call $self->template->config.

Disabling TT Object Caching

You can disable Template::Toolkit object caching entirely by providing a false value to the object_caching driver config parameter:

        $self->template->config(
            type          => 'TemplateToolkit',
            TemplateToolkit => {
                object_caching => 0,
            },
        );

TT Object Caching and Include Paths

The include_paths driver config parameter is not cached; it is set every time you call $self->template->load. So you can safely used cached TT objects even if the applications sharing the TT object need different include_paths.

CONFIGURATION

The the CGI::Application::Plugin::AnyTemplate::Driver::TemplateToolkit manpage driver accepts the following config parameters:

embed_tag_name

The name of the tag used for embedding components. Defaults to CGIAPP.

template_extension

If auto_add_template_extension is true, then the CGI::Application::Plugin::AnyTemplate manpage will append the value of template_extension to filename. By default the template_extension is .xhtml.

emulate_associate_query

This feature is now deprecated and will be removed in a future release.

If this config parameter is true, then the CGI::Application::Plugin::AnyTemplate::Driver::TemplateToolkit manpage will copy all of the webapp's query params into the template.

This is similar to what would happen if you used the HTML::Template manpage's associate feature with the webapp's query object:

    my $driver = HTML::Template->new(
        associate => $self->query,
    );

By default emulate_associate_query is false.

object_caching

Whether or not to cache the Template::Toolkit object in a persistent environment

By default, object_caching is enabled.

See TT OBJECT CACHING (singleton support), above.

storage_class

What class to use as the storage key when object caching is enabled.

By default, storage_class defaults to the package containing the subroutine that called $self->template->config.

See TT OBJECT CACHING (singleton support), above.

All other configuration parameters are passed on unchanged to Template::Toolkit.

required_modules

The required_modules function returns the modules required for this driver to operate. In this case: Template.

DRIVER METHODS

initialize: Initializes the TemplateToolkit driver. See the docs for the CGI::Application::Plugin::AnyTemplate::Base manpage for details.
render_template: Fills the Template::Toolkit object with $self->param; If the param emulate_associate_query is true, then set params for each of $self->{'webapp'}->query, mimicking the HTML::Template manpage's associate mechanism.; Also set up a the CGI::Application::Plugin::AnyTemplate::ComponentHandler manpage object so that the CGIAPP.embed callback will work.; Returns the output of the filled template as a string reference.; See the docs for the CGI::Application::Plugin::AnyTemplate::Base manpage for details.

ACKNOWLEDGEMENTS

Thanks to Cees Hek for discussing the issues of caching in a persistent environment. And also for his excellent the CGI::Application::Plugin::TT manpage module, from which I stole ideas and some code: especially the bit about how to change the include path in a TT object after you've initialized it.

AUTHOR

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

COPYRIGHT & LICENSE

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

CGI::Application::Plugin::AnyTemplate::Driver::TemplateToolkit - Template::Toolkit plugin to AnyTemplate