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NAME

Dancer2::Template::TemplateFlute - Template::Flute wrapper for Dancer2

VERSION

Version 0.203

DESCRIPTION

This class is an interface between Dancer2's template engine abstraction layer and the Template::Flute module.

In order to use this engine, use the template setting:

    template: template_flute

The default template extension is ".html".

LAYOUT

Each layout needs a specification file and a template file. To embed the content of your current view into the layout, put the following into your specification file, e.g. views/layouts/main.xml:

    <specification>
    <value name="content" id="content" op="hook"/>
    </specification>

This replaces the contents of the following block in your HTML template, e.g. views/layouts/main.html:

    <div id="content">
    Your content
    </div>

ITERATORS

Iterators can be specified explicitly in the configuration file as below.

  engines:
    template:
      template_flute:
        iterators:
          fruits:
            class: JSON
            file: fruits.json

FILTER OPTIONS

Filter options and classes can be specified in the configuration file as below.

  engines:
    template:
      template_flute:
        filters:
          currency:
            options:
              int_curr_symbol: "$"
          image:
            class: "Flowers::Filters::Image"

ADJUSTING URIS

We automatically adjust links in the templates if the value of request-path> is different from request-path_info>.

EMBEDDING IMAGES IN EMAILS

If you pass a value named email_cids, which should be an empty hash reference, all the images src attributes will be rewritten using the CIDs, and the reference will be populated with an hashref, as documented in Template::Flute

Further options for the CIDs should be passed in an optional value named cids. See Template::Flute for them.

DISABLE OBJECT AUTODETECTION

Sometimes you want to pass values to a template which are objects, but don't have an accessor, so they should be treated like hashrefs instead.

You can specify classes with the following syntax:

  engines:
    template:
      template_flute:
        autodetect:
          disable:
            - My::Class1
            - My::Class2

The class matching is checked by Template::Flute with isa, so any parent class would do.

LOCALIZATION

Templates can be localized using the Template::Flute::I18N module. You can define a class that provides a method which takes as first (and only argument) the string to translate, and returns the translated one. You have to provide the class and the method. If the class is not provided, no localization is done. If no method is specified, 'localize' will be used. The app will crash if the class doesn't provide such method.

Be sure to return the argument verbatim if the module is not able to translate the string.

Example configuration, assuming the class MyApp::Lexicon provides a try_to_translate method.

  engines:
    template:
      template_flute:
        i18n:
          class: MyApp::Lexicon
          method: try_to_translate

A class could be something like this:

  package MyTestApp::Lexicon;
  use Dancer2;

  sub new {
      my $class = shift;
      debug "Loading up $class";
      my $self = {
                  dictionary => {
                                 en => {
                                        'TRY' => 'Try',
                                       },
                                 it => {
                                        'TRY' => 'Prova',
                                       },
                                }
                 };
      bless $self, $class;
  }

  sub dictionary {
      return shift->{dictionary};
  }

  sub try_to_translate {
      my ($self, $string) = @_;
      my $lang = session('lang') || var('lang');
      return $string unless $lang;
      return $string unless $self->dictionary->{$lang};
      my $tr = $self->dictionary->{$lang}->{$string};
      defined $tr ? return $tr : return $string;
  }

  1;

Optionally, you can pass the options to instantiate the class in the configuration. Like this:

  engines:
    template:
      template_flute:
        i18n:
          class: MyApp::Lexicon
          method: localize
          options:
            append: 'X'
            prepend: 'Y'
            lexicon: 'path/to/po/files'

This will call

 MyApp::Lexicon->new(append => 'X', prepend => 'Y', lexicon => 'path/to/po/files');

when the engine is initialized, and will call the localize method on it to get the translations.

DEBUG TOOLS

If you set check_dangling in the engine stanza, the specification will run a check (using the Template::Flute::Specification's dangling method) against the template to see if you have elements of the specifications which are not bound to any HTML elements.

In this case a debug message is issued (so keep in mind that with higher logging level you are not going to see it).

Example configuration:

  engines:
    template:
      template_flute:
        check_dangling: 1

When the environment is set to development this feature is turned on by default. You can silence the logs by setting:

  engines:
    template:
      template_flute:
        disable_check_dangling: 1

FORMS

Dancers::Template::TemplateFlute has a form plugin Dancer2::Plugin::TemplateFlute which must be installed in order to use Template::Flute forms.

The token form is reserved for forms. It can be a single Dancer2::Plugin::TemplateFlute form object or an arrayref of Dancer2::Plugin::TemplateFlute form objects.

Typical usage for a single form.

XML Specification

  <specification>
  <form name="registration" link="name">
  <field name="email"/>
  <field name="password"/>
  <field name="verify"/>
  </form>
  </specification>

HTML

  <form class="frm-default" name="registration" action="/register" method="POST">
        <fieldset>
          <div class="reg-info">Info</div>
          <ul>
                <li>
                  <label>Email</label>
                  <input type="text" name="email"/>
                </li>
                <li>
                  <label>Password</label>
                  <input type="text" name="password"/>
                </li>
                <li>
                  <label>Confirm password</label>
                  <input type="text" name="verify" />
                </li>
                <li>
                  <input type="submit" value="Register" class="btn-submit" />
                </li>
          </ul>
        </fieldset>
  </form>

Code

  any [qw/get post/] => '/register' => sub {
      my $form = request->is_post
          ? form('registration', source => 'body')
          : form('registration', source => 'session' );
      my %values = %{$form->values};
      # VALIDATE, filter, etc. the values
      template register => {form => $form };
  };

Usage example for multiple forms

Specification

  <specification>
  <form name="registrationtest" link="name">
  <field name="emailtest"/>
  <field name="passwordtest"/>
  <field name="verifytest"/>
  </form>
  <form name="logintest" link="name">
  <field name="emailtest_2"/>
  <field name="passwordtest_2"/>
  </form>
  </specification>

HTML

  <h1>Register</h1>
  <form class="frm-default" name="registrationtest" action="/multiple" method="POST">
        <fieldset>
          <div class="reg-info">Info</div>
          <ul>
                <li>
                  <label>Email</label>
                  <input type="text" name="emailtest"/>
                </li>
                <li>
                  <label>Password</label>
                  <input type="text" name="passwordtest"/>
                </li>
                <li>
                  <label>Confirm password</label>
                  <input type="text" name="verifytest" />
                </li>
                <li>
                  <input type="submit" name="register" value="Register" class="btn-submit" />
                </li>
          </ul>
        </fieldset>
  </form>
  <h1>Login</h1>
  <form class="frm-default" name="logintest" action="/multiple" method="POST">
        <fieldset>
          <div class="reg-info">Info</div>
          <ul>
                <li>
                  <label>Email</label>
                  <input type="text" name="emailtest_2"/>
                </li>
                <li>
                  <label>Password</label>
                  <input type="text" name="passwordtest_2"/>
                </li>
                <li>
                  <input type="submit" name="login" value="Login" class="btn-submit" />
                </li>
          </ul>
        </fieldset>
  </form>

Code

  any [qw/get post/] => '/multiple' => sub {
      my ( $login_form, $registration_form );
      debug to_dumper({params});

      if (params->{login}) {
          $login_form = form('logintest', source => 'parameters');
          my %vals = %{$login->values};
          # VALIDATE %vals here
      }
      else {
          # pick from session
          $login_form = form('logintest', source => 'session');
      }

      if (params->{register}) {
          $registration_form = form('registrationtest', source => 'parameters');
          my %vals = %{$registration->values};
          # VALIDATE %vals here
      }
      else {
          # pick from session
          $registration_form = form('registrationtest', source => 'session');
      }
      template multiple => { form => [ $login_form, $registration_form ] };
  };

METHODS

default_tmpl_ext

Returns default template extension.

render TEMPLATE TOKENS

Renders template TEMPLATE with values from TOKENS.

SEE ALSO

Dancer2, Template::Flute

AUTHOR

Author of the original Dancer module:

Stefan Hornburg (Racke), <racke at linuxia.de>

Conversion to Dancer2:

Peter Mottram (SysPete), <peter@sysnix.com>

Author of the original version of this Dancer2 module:

William Carr (mrmaloof), <bill at bottlenose-wine.com>

BUGS

Please report any bugs or feature requests via the GitHub issue tracker at: https://github.com/interchange/Dancer2-Template-TemplateFlute/issues

SUPPORT

You can find documentation for this module with the perldoc command.

    perldoc Dancer2::Template::TemplateFlute

You can also look for information at:

LICENSE AND COPYRIGHT

Copyright 2011-2016 Stefan Hornburg (Racke) <racke@linuxia.de>.

This program is free software; you can redistribute it and/or modify it under the terms of either: the GNU General Public License as published by the Free Software Foundation; or the Artistic License.

See http://dev.perl.org/licenses/ for more information.