/ 
Catalyst-View-TT-0.23
River stage two • 60 direct dependents • 77 total dependents
/ Catalyst::View::TT

NAME

Catalyst::View::TT - Template View Class

SYNOPSIS

# 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');,
    'View::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 %]

DESCRIPTION

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 MyApp 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');
}

CONFIGURATION

There are a three different ways to configure your view class. The first way is to call the config() 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 new() 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 new() method (via $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 config() 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 NEXT if you redefine the new() 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.

DYNAMIC INCLUDE_PATH

Sometimes it is desirable to modify INCLUDE_PATH for your templates at run time.

Additional paths can be added to the start of INCLUDE_PATH via the stash as follows:

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

If you need to add paths to the end of INCLUDE_PATH, there is also an include_path() accessor available:

push( @{ $c->view('TT')->include_path }, qw/path/ );

Note that if you use include_path() to add extra paths to INCLUDE_PATH, you MUST check for duplicate paths. Without such checking, the above code will add "path" to INCLUDE_PATH at every request, causing a memory leak.

A safer approach is to use include_path() to overwrite the array of paths rather than adding to it. This eliminates both the need to perform duplicate checking and the chance of a memory leak:

@{ $c->view('TT')->include_path } = qw/path another_path/;

If you are calling render directly then you can specify dynamic paths by having a additional_template_paths key with a value of additonal directories to search. See "CAPTURING TEMPLATE OUTPUT" for an example showing this.

RENDERING VIEWS

The view plugin renders the template specified in the template 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 $c->match. In the above example, this would be message.

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

sub default : Private {
    my ( $self, $c ) = @_;
    $c->stash->{template} = 'message.tt2';
    $c->stash->{message}  = 'Hello World!';
    $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 $c->response->body.

CAPTURING TEMPLATE OUTPUT

If you wish to use the output of a template for some other purpose than displaying in the response, e.g. for sending an email, this is possible using Catalyst::Plugin::Email and the render method:

sub send_email : Local {
  my ($self, $c) = @_;
  
  $c->email(
    header => [
      To      => 'me@localhost',
      Subject => 'A TT Email',
    ],
    body => $c->view('TT')->render($c, 'email.tt', {
      additional_template_paths => [ $c->config->{root} . '/email_templates'],
      email_tmpl_param1 => 'foo'
      }
    ),
  );
# Redirect or display a message
}

TEMPLATE PROFILING

See TIMER property of the config method.

METHODS

new

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

process

Renders the template specified in $c->stash->{template} or $c->action (the private name of the matched action. Calls render to perform actual rendering. Output is stored in $c->response->body.

render($c, $template, \%args)

Renders the given template and returns output, or a Template::Exception object upon error.

The template variables are set to %$args if $args is a hashref, or $$c->stash otherwise. In either case the variables are augmented with base set to << $c-req->base >>, c to $c and name to $c->config->{name}. Alternately, the CATALYST_VAR configuration item can be defined to specify the name of a template variable through which the context reference ($c) can be accessed. In this case, the c, base and name variables are omitted.

$template can be anything that Template::process understands how to process, including the name of a template file or a reference to a test string. See Template::process for a full list of supported formats.

template_vars

Returns a list of keys/values to be used as the catalyst variables in the template.

config

This method allows your view subclass to pass additional settings to the TT configuration hash, or to set the options as below:

CATALYST_VAR

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 %]
TIMER

If you have configured Catalyst for debug output, and turned on the TIMER setting, Catalyst::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) -->
TEMPLATE_EXTENSION

a sufix to add when looking for templates bases on the match 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.

HELPERS

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.

SEE ALSO

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

AUTHORS

Sebastian Riedel, sri@cpan.org

Marcus Ramberg, mramberg@cpan.org

Jesse Sheidlower, jester@panix.com

Andy Wardley, abw@cpan.org

COPYRIGHT

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