=back
-If you're unfamiliar with MVC and design patterns, you may want to check out the
-original book on the subject, I<Design Patterns>, by Gamma, Helm, Johson and
-Vlissides, also known as the Gang of Four (GoF). You can also just google it.
-Many, many web application frameworks are based on MVC, including all those
-listed above.
+If you're unfamiliar with MVC and design patterns, you may want to check
+out the original book on the subject, I<Design Patterns>, by Gamma,
+Helm, Johnson, and Vlissides, also known as the Gang of Four (GoF). You
+can also just Google it. Many, many web application frameworks are
+based on MVC, including all those listed above.
=head3 Flexibility
=back
-=head4 B<Built-in actions in controllers/autochaining>
+=head4 Built-in actions in controllers/autochaining
Package MyApp::C::Foo;
sub begin : Private { }
action; in that case, the request will go straight to the finalize
stage, without processing further actions.
-=head4 B<URL Path Handling>
+=head4 URL Path Handling
You can pass variable arguments as part of the URL path. In this case,
you must use regex action keys with '^' and '$' anchors, and the
So Catalyst would never mistakenly dispatch the first two URLs to the
'^foo$' action.
-=head4 B<Parameter Processing>
+=head4 Parameter Processing
Parameters passed in the URL query string are handled with methods in
the L<Catalyst::Request> class. The C<param> method is functionally
1;
-You don't have to C<use> or otherwise register Models, Views, and Controllers.
-Catalyst automatically discovers and instantiates them when you call C<setup> in
-the main application. All you need to do is put them in directories named for
-each Component type. Notice that you can use some very terse aliases for each
-one.
+You don't have to C<use> or otherwise register Models, Views, and
+Controllers. Catalyst automatically discovers and instantiates them
+when you call C<setup> in the main application. All you need to do is
+put them in directories named for each Component type. Notice that you
+can use some very terse aliases for each one.
=over 4
script/myapp_create.pl view TT TT
-where the first C<TT> tells the script to create a Template Toolkit
-view, and the second tells the script that its name should be C<TT>.)
+where the first C<TT> tells the script that the name of the view should
+be C<TT>, and the second that it should be a Template Toolkit view.)
This gives us a process() method and we can now just do
$c->forward('MyApp::V::TT') to render our templates. The base class makes
$c->forward('MyApp::V::TT');
}
-You normally render templates at the end of a request, so it's a perfect use for
-the global C<end> action.
+You normally render templates at the end of a request, so it's a perfect
+use for the global C<end> action.
Also, be sure to put the template under the directory specified in
-C<$c-E<gt>config-E<gt>{root}>, or you'll be forced to look at our eyecandy debug
-screen. ;)
+C<$c-E<gt>config-E<gt>{root}>, or you'll be forced to look at our
+eyecandy debug screen. ;)
=head4 Models
1;
+ # Then, in a TT template:
The id is [% item.data %]
+Models do not have to be part of your Catalyst application; you
+can always call an outside module that serves as your Model:
+
+ # in a Controller
+ sub list : Local {
+ my ( $self, $c ) = @_;
+ $c->stash->{template} = 'list.tt';
+ use Some::Outside::CDBI::Module;
+ my @records = Some::Outside::CDBI::Module->retrieve_all;
+ $c->stash->{records} = \@records;
+ }
+
+But by using a Model that is part of your Catalyst application, you gain
+several things: you don't have to C<use> each component, Catalyst will
+find and load it automatically at compile-time; you can C<forward> to
+the module, which can only be done to Catalyst components; and only
+Catalyst components can be fetched with
+C<$c-E<gt>comp('MyApp::M::SomeModel')>.
+
+Happily, since many people have existing Model classes that they
+would like to use with Catalyst (or, conversely, they want to
+write Catalyst models that can be used outside of Catalyst, e.g.
+in a cron job), it's trivial to write a simple component in
+Catalyst that slurps in an outside Model:
+
+ package MyApp::M::Catalog;
+ use base qw/Catalyst::Base Some::Other::CDBI::Module::Catalog/;
+ 1;
+
+and that's it! Now C<Some::Other::CDBI::Module::Catalog> is part of your
+Cat app as C<MyApp::M::Catalog>.
+
=head4 Controllers
Multiple controllers are a good way to separate logical domains of your
package MyApp::C::Login;
- sign-in : Local { }
- new-password : Local { }
- sign-out : Local { }
+ sub sign-in : Local { }
+ sub new-password : Local { }
+ sub sign-out : Local { }
package MyApp::C::Catalog;