is used to pass information between components and provide access to
Catalyst and plugin functionality.
-B<Note:> Catalyst actions are regular Perl methods, but they make use
-of Nicholas Clark's C<attributes> module (that's the "C<: Local>" next
-to the C<sub list> in the code above) to provide additional
-information to the Catalyst dispatcher logic. Many newer Catalyst
-applications are switching to the use of "Literal" C<:Path> actions
-and C<Args> attribute in lieu of C<: Local> and C<: Private>. For
-example, C<sub any_method :Path :Args(0)> can be used instead of C<sub
-index :Private> (because no path was supplied to C<Path> it matches
-the "empty" URL in the namespace of that module... the same thing
-C<sub index> would do) or C<sub list :Path('list') :Args(0)> could be
-used instead of the C<sub list : Local> above (the C<list> argument to
-C<Path> would make it match on the URL C<list> under C<books>, the
-namespace of the current module). See "Action Types" in
-L<Catalyst::Manual::Intro|Catalyst::Manual::Intro> as well as Part 5
-of this tutorial (Authentication) for additional information. Another
-popular but more advanced feature is C<Chained> actions that allow a
-single URL to "chain together" multiple action method calls, each with
-an appropriate number of arguments (see
-L<Catalyst::DispatchType::Chained|Catalyst::DispatchType::Chained> for
-details).
+Catalyst actions are regular Perl methods, but they make use
+of attributes (the "C<: Local>" next to the "C<sub list>" in the code
+above) to provide additional information to the Catalyst dispatcher
+logic (note that the space between the colon and the attribute name is
+optional... you will see them written both ways). Over time, the
+recommended style for most Catalyst applications has changed:
+
+=over 4
+
+=item * From "C<:Local>" and "C<:Private>"
+
+=item * To "C<:Path>" and "C<:Args>"
+
+=item * To "C<:Chained>"
+
+=back
+
+Although all three styles work just fine, the newer forms offer more
+advanced capbilities and allow you to be more expressive with the URIs
+that your application uses.
+
+Here is a quick summary of the most commonly used action types:
+C<Local>, C<Private>, C<Path> and C<Chained>:
+
+=over 4
+
+=item *
+
+B<Local and Private> -- In the past, the majority of applications have
+traditionally used C<Local> actions for items that respond to user
+requests and C<Private> actions for those that do not directly respond
+to user input.
+
+=over 4
+
+There are five types of build-in C<Private> actions: C<begin>,
+C<end>, C<default>, C<index>, and C<auto>.
+
+=item *
+
+With C<begin>, C<end>, C<default>, C<index> private actions, only the
+most specific action of each type will be called. For example, if you
+define a C<begin> action in your controller it will I<override> a
+C<begin> action in your application/root controller -- I<only> the
+action in your controller will be called.
+
+=item *
+
+Unlike the other actions where only a single method is called for each
+request, I<every> auto action along the chain of namespaces will be
+called. Each C<auto> action will be called I<from the application/root
+controller down through the most specific class>.
+
+=back
+
+=item *
+
+B<Path> -- C<Path> actions were the next style of action types to
+become popular and essentially provide a limited subset of what can be
+found done with Chained actions. You can match on different portions
+of the URI (for example C<Path('list')> in
+C<lib/MyApp/Controller/Books.pm> would match on the URL
+C<http://localhost:3000/books/list> but C<Path('/list')> would match
+on C<http://localhost:3000/list>) and it let's you be very specific with
+what arguments each controller method will accept. See
+L<Catalyst::Manual::Intro/Action_types> for more information and a few
+examples.
+
+=item *
+
+B<Chained> -- Newer Catalyst applications tend to use the Chained
+dispatch form of action types because of its power and flexibility.
+It allows a series of controller methods to automatically be dispatched
+to service a single user request. See
+L<Catalyst::Manual::Tutorial::BasicCRUD|Catalyst::Manual::Tutorial::BasicCRUD>
+and L<Catalyst::DispatchType::Chained|Catalyst::DispatchType::Chained>
+for more information on chained actions.
+
+=back
+
+You should refer to L<Catalyst::Manual::Intro/Action_types> for
+additional information and for coverage of some lesser-used action
+types not discussed here (C<Regex>, C<LocalRegex> and C<Global>).
=head1 CATALYST VIEWS
projects / catagits/Catalyst-Manual.git / blobdiff