[Catalyst] RESTy Chained actions

[Stephen Howard]

I may be off the mark on what you're trying to do, but here goes.

In my brief experience with catalyst, inheritance doesn't do much for  
you when constructing actions.
I believe that chained actions are pretty tightly bound to the urls  
you are building, so there's no way to reuse them for different urls.   
That said, something I often do is $c->forward my way to common  
private functions, rather than try to do it through inheritance.  So,  
from that same project:

sub find_tutorial :Chained('/') PathPart('tutorials') CaptureArgs(1) {

     $_[1]->forward('/exists',['tutorial' => 'Tutorial' => $_[2] ])
}
sub find_comment :Chained('find_tutorial') PathPart('comments')  
CaptureArgs(1) {

     $_[1]->forward('/exists',['comment' => 'Comment::Thread' =>  
$_[2] ])
}

where, 'exists' is defined in my root controller as:

sub exists :Private {

     my( $self, $c, $name, $class, $id ) = @_;

     unless( $c->stash->{$name} = $c->model("DB::$class")->find($id) ) {
         $c->res->status('404');
         $c->detach('/default');
     }
}

HTH

Stephen

On Jun 29, 2010, at 6:06 AM, John Lifsey - Contractor - 5595 wrote:

>
> On 6/25/10 12:08 PM, Stephen Howard wrote:
>> /tutorials
>> /tutorials/*
>> /tutorials/*/comments
>> /tutorials/*/comments/*
>> /tutorials/*/comments/*/replies
>> /tutorials/*/comments/*/replies/*
>>
>> #
>> ------------------------------------------------------------------------------
>>
>> sub list :Chained('/') PathPart('tutorials') Args(0) :
>> ActionClass('REST') {}
>>
>> sub list_GET { ... }
>> sub list_POST { ... }
>> sub list_HEAD { ... }
>>
>> #
>> ------------------------------------------------------------------------------
>>
>> sub find_tutorial :Chained('/') PathPart('tutorials')  
>> CaptureArgs(1) {
>> ... }
>>
>> #
>> ------------------------------------------------------------------------------
>>
>> sub single :Chained('find_tutorial') PathPart('') Args(0)
>> ActionClass('REST') { ... }
>> sub single_GET { ... }
>> sub single_POST { ... }
>>
>> #
>> ------------------------------------------------------------------------------
>>
>> sub comments :Chained('find_tutorial') PathPart('comments') Args(0)
>
> Well, if you teach a man to fish, apparently he'll ask you to teach  
> him how to fly spaceships next.
>
> While this example worked well, it led me to another related  
> problem. I have a parent Controller class for typical behavior on a  
> resource from which I inherit and override as needed for each type  
> of resource.
>
> package MyBaseController;
> extends 'Catalyst::Controller::REST';
>
> sub index : Chained PathPrefix Args(0) ActionClass('REST') {}
> sub find : Chained PathPrefix CaptureArgs(1) {}
> sub single : Chained('find') PathPart('') Args(0) {}
> etc..
>
> 1;
>
> Using the previous poster's example this works just fine in
> MyApp::Controller::Tutorial
>
> but it will not work for MyApp::Controller::Tutorial::Comments
> At first, from looking at the documentation I thought that setting  
> the controller config key "path" to a regex or "/tutorial/*/" might  
> do the trick, but alas it does not.
>
> This is further complicated by my desire to break from the previous  
> example and allow Comments to be at the same hierarchical level as  
> Tutorial. That is to say:
>
> MyApp::Controller::Tutorial ISA MyBaseController;
> and
> MyApp::Controller::Comments ISA MyBaseController;
>
> So that I could reference a particular comment ID at /myapp/comments/ 
> * or at /myapp/tutorial/*/comments/*
>
> Upon documentation review I thought __PACKAGE__- 
> >config(action=>{'*'=>{ blah, blah }}); would be my salvation, but  
> it appears that '*' doesn't actually work in myapp, at least as  
> written in the documentation.
>
> Now that I've gotten myself worked entirely into a lather thinking  
> in circles it's time to request insight from the crowd. Any  
> suggestions?
>
>
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