[Catalyst-dev] Extensible Catalyst Applications: How?!

[Eden Cardim]

On Tue, Jun 2, 2009 at 7:45 AM, Ido Perelmutter <ido50 at yahoo.com> wrote:
>
> Hi everyone.
>
> For the last week and a half I've been trying to figure out how to make my Catalyst application extensible, to no avail.
>
> SCENARIO:
>
> 1. I have written a Catalyst application called MyApp (The name is a trademark belonging to me so don't steal it).
>
> 2. I want people (and me too) to be able to create plugins that extend the functionality of MyApp.
>
> 3. I want to create a plugin for MyApp, called "MyPlugin". This plugin in itself is a (near-)complete Catalyst application. It has its own controllers, models, views, etc.
>
> 4. I want to "mount" this plugin to some path on MyApp, such that all requests for a path beginning with "/myplugin", for example, are to be routed to MyPlugin's controllers.
>
> 5. The context is, of course, to be shared between the two. MyPlugin is seamlessly integrated into MyApp, but any MyPlugin logic is not to be added to MyApp. For example, I do not need to change MyApp.pm to add some MyPlugin specific code, like $c->controller eq $c->controller('MyPlugin::ShootMe') for example.
>
> 6. MyPlugin is to be, well, pluggable. I can enable and disable it as/when I wish.
>
> WHAT I'M DOING NOW:
>
> 1. I develop MyPlugin as an integral part of MyApp, making all it's controllers MyApp-controllers, and update myapp.conf appropriately (adding a realm perhaps and MyPlugin-related configurations).
>
> 2. I add MyPlugin logic to MyApp.pm and maybe other files.
>
> 3. I shoot myself in the head.
>
> WHY THIS IS BAD:
>
> 1. It's not pluggable.
>
> 2. I have interfered with MyApp's code (including myapp.conf) - very bad for development. While one (MyPlugin) depends on the other (MyApp), they should be separate entities.
>
> 3. I have shot myself in the head, that can't be good.
>
> So, my question is, what am I to do in order to make my app extensible, at least in the way described above? Do I definitely need to create an API for MyApp? (I will anyway, but is that necessary for the scenario above?).
>
> And also, how can I overcome potential problems like MyPlugin requiring the presence of Catalyst plugins not loaded by MyApp.pm?
>
> Any help heavenly appreciated,
> Ido Perelmutter.

Why not just develop separate apps and deploy them to specific paths
via whatever backend engine you're using?

-- 
   Eden Cardim       Need help with your Catalyst or DBIx::Class project?
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