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

[Ido Perelmutter]

This is possible, but has some drawbacks:

1. Both apps are entirely separate. The parent-plugin connection is kinda lost. I can't handle the plugins from inside the parent app.

2. Operation is engine dependant, which is not that bad but means more headaches for the end-user.

3. Two catalyst apps means more memory usage, cpu usage, etc. Not good, especially for apps running on shared or VPS hosting.

4. While this may answer the "separate paths" scenario, my app is still not extensible and people will not write plugins for it.

Thanks,
Ido.

--- On Tue, 6/2/09, Eden Cardim <edencardim at gmail.com> wrote:

> From: Eden Cardim <edencardim at gmail.com>
> Subject: Re: [Catalyst-dev] Extensible Catalyst Applications: How?!
> To: ido50 at yahoo.com, "Development of the elegant MVC web framework" <catalyst-dev at lists.scsys.co.uk>
> Date: Tuesday, June 2, 2009, 4:30 PM
> 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
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>