uses to determine how to match in incoming request to an action (or action chain)
in a controller.
+=head2 Request to Controller/Action Matching
+
+L<Catalyst> maps requests to action using a 'longest path wins' approach. That means
+that if the request is '/foo/bar/baz' That means the action 'baz' matches:
+
+ package MyApp::Controller::Foo;
+
+ use Moose;
+ use MooseX::MethodAttributes
+
+ extends 'Catalyst::Controller';
+
+ sub bar :Path('bar') Args(1) { ...}
+ sub baz :Path('bar/baz') Args(0) { ... }
+
+Path length matches take precidence over all other types of matches (included HTTP
+Method, Scheme, etc.). The same holds true for Chained actions. Generally the
+chain that matches the most PathParts wins.
+
+=head2 Args(N) versus Args
+
+'Args' matches any number of args. Because this functions as a sort of catchall, we
+treat 'Args' as the lowest precedence of any Args(N) when N is 0 to infinity. An
+action with 'Args' always get the last chance to match.
+
+=head2 When two or more actions match a given Path
+
+Sometimes two or more actions match the same path and all have the same pathpart
+length. For example:
+
+ package MyApp::Controller::Root;
+
+ use Moose;
+ use MooseX::MethodAttributes
+
+ extends 'Catalyst::Controller';
+
+ sub root :Chained(/) CaptureArgs(0) { }
+
+ sub one :Chained(root) PathPart('') Args(0) { }
+ sub two :Chained(root) PathPart('') Args(0) { }
+ sub three :Chained(root) PathPart('') Args(0) { }
+
+ __PACKAGE__->meta->make_immutable;
+
+In this case the last defined action wins (for the example that is action 'three').
+
+This is most common to happen when you are using action matching beyond paths, such as
+when using method matching:
+
+ package MyApp::Controller::Root;
+
+ use Moose;
+ use MooseX::MethodAttributes
+
+ extends 'Catalyst::Controller';
+
+ sub root :Chained(/) CaptureArgs(0) { }
+
+ sub any :Chained(root) PathPart('') Args(0) { }
+ sub get :GET Chained(root) PathPart('') Args(0) { }
+
+ __PACKAGE__->meta->make_immutable;
+
+In the above example GET /root could match both actions. In this case you should define
+your 'catchall' actions higher in the controller.
+
=head2 Type Constraints in Args and Capture Args
Beginning in Version 5.90090+ you may use L<Moose>, L<MooseX::Types> or L<Type::Tiny>
use Moose;
use MooseX::MethodAttributes;
+ use MooseX::Types::Moose qw(Int);
extends 'Catalyst::Controller';
More than one argument may be added by comma separating your type constraint names, for
example:
+ use Types::Standard qw/Int Str/;
+
sub find :Path('') Args(Int,Int,Str) {
my ($self, $c, $int1, $int2, $str) = @_;
}
-Would require three arguments, an integer, integer and a string.
+Would require three arguments, an integer, integer and a string. Note in this example we
+constrained the args using imported types via L<Types::Standard>. Although you may use
+stringy Moose types, we recommend imported types since this is less ambiguous to your readers.
+If you want to use Moose stringy types. you must quote them (either "Int" or 'Int' is fine).
+
+Conversely, you should not quote types that are imported!
=head3 Using type constraints in a controller
use Moose;
use MooseX::MethodAttributes;
- use Types::Standard qw/StrMatch/;
+ use Types::Standard qw/StrMatch Int/;
extends 'Catalyst::Controller';
actions. The only difference is that you may declare type constraints on CaptureArgs as
well as Args. For Example:
+ use Types::Standard qw/Int Tuple/;
+
sub chain_base :Chained(/) CaptureArgs(1) { }
sub any_priority_chain :GET Chained(chain_base) PathPart('') Args(1) { }
Please note that your declared type constraint names will now appear in the debug console.
-=head1 Conclusion
-
- TBD
-
=head1 Author
John Napiorkowski L<jjnapiork@cpan.org|email:jjnapiork@cpan.org>