DOKK / manpages / debian 11 / libmason-perl / Mason::Component.3pm.en
Mason::Component(3pm) User Contributed Perl Documentation Mason::Component(3pm)

Mason::Component - Mason Component base class

Every Mason component corresponds to a unique class that inherits, directly or indirectly, from this base class.

A new instance of the component class is created whenever a component is called - whether via a top level request, "<& &>" tags, or an << $m->comp >> call. A component instance is only valid for the Mason request in which it was created.

We leave this class as devoid of built-in methods as possible, allowing you to create methods in your own components without worrying about name clashes.

This is the standard call chain for the page component (the initial component of a request).

    handle -> render -> wrap -> main

In many cases only "main" will actually do anything.

This is the top-most method called on the page component. Its job is to decide how to handle the request, e.g.
  • throw an error (e.g. permission denied)
  • take some action and redirect (e.g. if handling a form in a web environment)
  • defer to another component via "$m->go"
  • render the page

It should not output any content itself. By default, it simply calls render.

This method is invoked from handle on the page component. Its job is to output the full content of the page. By default, it simply calls wrap.
This method is invoked from render on the page component. By convention, "wrap" is an augmented method, with each superclass calling the next subclass. This is useful for cascading templates in which the top-most superclass generates the surrounding content. 

    <%augment wrap>
      <h3>Subtitle section</h3>
      <div class="main">
        <% inner() %>
      </div>
    </%augment>

By default, "wrap" simply calls "inner()" to go to the next subclass, and then main at the bottom subclass.

To override a component's parent wrapper, a component can define its own "wrap" using "method" instead of "augment":

    <%method wrap>
      <h3>Parent wrapper will be ignored</h3>
      <% inner() %>
    </%method>

To do no wrapping at all, call the component class method "no_wrap":

    <%class>
    CLASS->no_wrap;
    </%class>
This method is invoked when a non-page component is called, and from the default wrap method as well. It consists of the code and output in the main part of the component that is not inside a "<%method>" or "<%class>" tag.

A convenience method that redefines render to call main instead of wrap, thus skipping any content wrapper inherited from parent. 

    <%class>
    CLASS->no_wrap;
    </%class>
This method is called when the request path has a path_info portion, to determine whether the path_info is allowed. Default is false. See Mason::Manual::RequestDispatch. 

    <%class>
    method allow_path_info { 1 }
    </%class>

Returns the hashref of arguments passed to this component's constructor, e.g. the arguments passed in a component call.
Returns the Mason::Component::ClassMeta object associated with this component class, containing information such as the component's path and source file. 

    my $path = $self->cmeta->path;
Returns the current request. This is also available via $m inside Mason components.

Mason

Jonathan Swartz <swartz@pobox.com>

This software is copyright (c) 2012 by Jonathan Swartz.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.

2021-01-06 perl v5.32.0