Catalyst::View::TT - Template View Class

# use the helper to create View myapp_create.pl view TT TT

# configure in lib/MyApp.pm

    MyApp->config({
        name     => 'MyApp',
        root     => MyApp->path_to('root');,
        'V::TT' => {
            # any TT configurations items go here
            INCLUDE_PATH => [
              MyApp->path_to( 'root', 'src' ), 
              MyApp->path_to( 'root', 'lib' ), 
            ],
            PRE_PROCESS        => 'config/main',
            WRAPPER            => 'site/wrapper',
            TEMPLATE_EXTENSION => '.tt',

            # two optional config items
            CATALYST_VAR => 'Catalyst',
            TIMER        => 1,
        },
    });

# render view from lib/MyApp.pm or lib/MyApp::C::SomeController.pm

    sub message : Global {
        my ( $self, $c ) = @_;
        $c->stash->{template} = 'message.tt2';
        $c->stash->{message}  = 'Hello World!';
        $c->forward('MyApp::V::TT');
    }

# access variables from template

    The message is: [% message %].

    # example when CATALYST_VAR is set to 'Catalyst'
    Context is [% Catalyst %]          
    The base is [% Catalyst.req.base %] 
    The name is [% Catalyst.config.name %]

    # example when CATALYST_VAR isn't set
    Context is [% c %]
    The base is [% base %]
    The name is [% name %]

This is the Catalyst view class for the Template Toolkit. Your application should defined a view class which is a subclass of this module. The easiest way to achieve this is using the myapp_create.pl script (where myapp should be replaced with whatever your application is called). This script is created as part of the Catalyst setup.

    $ script/myapp_create.pl view TT TT

This creates a MyApp::V::TT.pm module in the lib directory (again, replacing CWMyApp with the name of your application) which looks something like this:

    package FooBar::V::TT;

    use strict;
     use base 'Catalyst::View::TT';

    __PACKAGE__->config->{DEBUG} = 'all';

Now you can modify your action handlers in the main application and/or controllers to forward to your view class. You might choose to do this in the end() method, for example, to automatically forward all actions to the TT view class.

    # In MyApp or MyApp::Controller::SomeController

    sub end : Private {
        my( $self, $c ) = @_;
        $c->forward('MyApp::V::TT');
    }

There are a three different ways to configure your view class. The first way is to call the CWconfig() method in the view subclass. This happens when the module is first loaded.

    package MyApp::V::TT;

    use strict;
    use base 'Catalyst::View::TT';

    MyApp::V::TT->config({
        INCLUDE_PATH => [
            MyApp->path_to( 'root', 'templates', 'lib' ),
            MyApp->path_to( 'root', 'templates', 'src' ),
        ],
        PRE_PROCESS  => 'config/main',
        WRAPPER      => 'site/wrapper',
    });

The second way is to define a CWnew() method in your view subclass. This performs the configuration when the view object is created, shortly after being loaded. Remember to delegate to the base class CWnew() method (via CW$self->NEXT::new() in the example below) after performing any configuration.

    sub new {
        my $self = shift;
        $self->config({
            INCLUDE_PATH => [
                MyApp->path_to( 'root', 'templates', 'lib' ),
                MyApp->path_to( 'root', 'templates', 'src' ),
            ],
            PRE_PROCESS  => 'config/main',
            WRAPPER      => 'site/wrapper',
        });
        return $self->NEXT::new(@_);
    }

The final, and perhaps most direct way, is to define a class item in your main application configuration, again by calling the uniquitous CWconfig() method. The items in the class hash are added to those already defined by the above two methods. This happens in the base class new() method (which is one reason why you must remember to call it via CWNEXT if you redefine the CWnew() method in a subclass).

    package MyApp;

    use strict;
    use Catalyst;

    MyApp->config({
        name     => 'MyApp',
        root     => MyApp->path_to('root'),
        'V::TT' => {
            INCLUDE_PATH => [
                MyApp->path_to( 'root', 'templates', 'lib' ),
                MyApp->path_to( 'root', 'templates', 'src' ),
            ],
            PRE_PROCESS  => 'config/main',
            WRAPPER      => 'site/wrapper',
        },
    });

Note that any configuration items defined by one of the earlier methods will be overwritten by items of the same name provided by the latter methods.

It is sometimes needed to dynamically add additional paths to the INCLUDE_PATH variable of the template object. This can be done by setting 'additional_include_paths' on stash to a referrence to an array with additional paths:

    $c->stash->{additional_template_paths} = [$c->config->{root} . '/test_include_path'];

The view plugin renders the template specified in the CWtemplate item in the stash.

    sub message : Global {
        my ( $self, $c ) = @_;
        $c->stash->{template} = 'message.tt2';
        $c->forward('MyApp::V::TT');
    }

If a class item isn't defined, then it instead uses the current match, as returned by CW$c->match. In the above example, this would be CWmessage.

The items defined in the stash are passed to the Template Toolkit for use as template variables.

sub message : Global { sub default : Private { my ( CW$self, CW$c ) = CW@_; CW$c->stash->{template} = 'message.tt2'; CW$c->stash->{message} = 'Hello World!'; CW$c->forward('MyApp::V::TT'); }

A number of other template variables are also added:

    c      A reference to the context object, $c
    base   The URL base, from $c->req->base()
    name   The application name, from $c->config->{ name }

These can be accessed from the template in the usual way:

<message.tt2>:

    The message is: [% message %]
    The base is [% base %]
    The name is [% name %]

The output generated by the template is stored in CW$c->response->output.

new

The constructor for the TT view. Sets up the template provider, and reads the application config.

process

Renders the template specified in CW$c->stash->{template} or CW$c->request->match. Template variables are set up from the contents of CW$c->stash, augmented with CWbase set to CW$c->req->base, CWc to CW$c and CWname to CW$c->config->{name}. Alternately, the CWCATALYST_VAR configuration item can be defined to specify the name of a template variable through which the context reference (CW$c) can be accessed. In this case, the CWc, CWbase and CWname variables are omitted. Output is stored in CW$c->response->output.

template_vars

Returns a list of keys/values to be used as the variables in the template. Allows you to change the name of the Catalyst context object. If set, it will also remove the base and name aliases, so you will have access them through <context>. For example:

    MyApp->config({
        name     => 'MyApp',
        root     => MyApp->path_to('root'),
        'V::TT' => {
            CATALYST_VAR => 'Catalyst',
        },
    });

message.tt2:

    The base is [% Catalyst.req.base %]
    The name is [% Catalyst.config.name %]

If you have configured Catalyst for debug output, and turned on the TIMER setting, CWCatalyst::View::TT will enable profiling of template processing (using Template::Timer). This will embed HTML comments in the output from your templates, such as:

    <!-- TIMER START: process mainmenu/mainmenu.ttml -->
    <!-- TIMER START: include mainmenu/cssindex.tt -->
    <!-- TIMER START: process mainmenu/cssindex.tt -->
    <!-- TIMER END: process mainmenu/cssindex.tt (0.017279 seconds) -->
    <!-- TIMER END: include mainmenu/cssindex.tt (0.017401 seconds) -->

    ....

    <!-- TIMER END: process mainmenu/footer.tt (0.003016 seconds) -->

a sufix to add when looking for templates bases on the CWmatch method in Catalyst::Request. For example:

  package MyApp::C::Test;
  sub test : Local { .. }

Would by default look for a template in <root>/test/test. If you set TEMPLATE_EXTENSION to '.tt', it will look for <root>/test/test.tt.

The Catalyst::Helper::View::TT and Catalyst::Helper::View::TTSite helper modules are provided to create your view module. There are invoked by the myapp_create.pl script:

    $ script/myapp_create.pl view TT TT

    $ script/myapp_create.pl view TT TTSite

The Catalyst::Helper::View::TT module creates a basic TT view module. The Catalyst::Helper::View::TTSite module goes a little further. It also creates a default set of templates to get you started. It also configures the view module to locate the templates automatically.

Catalyst, Catalyst::Helper::View::TT, Catalyst::Helper::View::TTSite, Template::Manual

Sebastian Riedel, CWsri@cpan.org

Marcus Ramberg, CWmramberg@cpan.org

Jesse Sheidlower, CWjester@panix.com

Andy Wardley, CWabw@cpan.org

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