Quicksilver and Colloquy plugins (was Re: [Pyobjc-dev] wrapping non-framework code)

[<yt...@us...>]

On Wed, 4 Aug 2004 21:13:26 +0200, "Ronald Oussoren"
<ron...@ma...> said:
> 
> On 1-aug-04, at 1:10, yt...@us... wrote:
> > I'd like to try writing plugins for the Colloquy IRC client using
> > PyObjC,
> > but as far as I can tell from their sdk, they don't provide the pieces
> > I'd need to use in the form of a bundle.  I guessed this from examining
> > the content of:
> >
> >   http://colloquy.info/downloads/plugin-sdk.zip
> 
> 
> I finally got around downloading this.
> 
> The classes seem to be defined in the main bundle, you could try using 
> NSBundle.mainBundle().bundlePath() as an argument to loadBundle. 

Bob sent me this advice too (-;  I performed some limited testing 
and I think it works.  Thanks to both of you!

> Another option is a more tradition approach: use objc.classList() and 
> add all classes whose name starts with 'JV'  or 'MV' to your module.

I'll keep this approach in my for the future -- nice to have options.

> The header files contain a number of enum definitions, you can use our 
> codegenerator scripts to extract those, but I wouldn't do that here (at 
> least not until we refactor those scripts).

Thanks for the pointer.  I'll have a look at those scripts.  Are these
the
ones located in the CodeGenerators directory?

> > [2] Though I'm having some trouble getting multiple PyObjC plugins to
> > play
> > well together -- but more on this in another message.
> 
> Could you elaborate on that?

Ok, let me give some background on what I did with Quicksilver plugins.

Quicksilver plugins are bundles, and in addition to specifying the
plugin's 
principal class via its Info.plist, one can specify class names which 
provide various types of functionality.  For example, in the
QSRegistration 
section of the Info.plist of one of my plugins there is:

		<key>QSObjectSources</key>
		<dict>
			<key>YTAtomObjectSource</key>
			<string>YTAtomObjectSource</string>
		</dict>

Here YTAtomObjectSource is a subclass of QSObjectSource - an abstract
class
which represents a 'source' of objects which Quicksilver is meant to 
handle.  (In this specific case, the source provides Atom API
endpoints.)

Most of my plugin is written in Python (e.g. the class
YTAtomObjectSource),
and I arranged for the principal class' load method to set up the
interface w/ Python and load my python code.  The nice thing about the
Quicksilver plugin approach [1] is that I can use the principal class
just to 
do set up and Quicksilver makes use of what's defined in QSRegistration
as 
entry points in to the functionality which the plugin provides.

My initial approach was based on what I found at:

  http://pyobjc.sourceforge.net/doc/extending_objc_with_python.php

This worked fine for when there was only one plugin using Python, but
not for using multiple plugins at the same time.  One of the plugins
would function normally, but the others would not -- though they all
functioned properly if used individually.  One of my suspicions as to 
the cause was that each of them was calling objc.loadBundle on the same 
bundle (while being loaded by PyRun_SimpleFile) -- but I didn't manage 
to confirm this as a factor.

After much hair-pulling, I extracted and applied some of the
generated-code 
section from pluginbuilder.py -- mostly related to avoiding
PyRun_SimpleFile 
and __main__ (does that interpretation sound right?) -- and now I am
able to use multiple PyObjC plugins in the same Quicksilver session.

I hope that was understandable.


[1] Whereas I'm struggling with trying to write a plugin for Colloquy
using 
PyObjC.  I see that I can specify a principal class, and this seems the
logical
place to set up the interface (bridge?) w/ Python, but once that's done,
IIUC, Colloquy will expect to call methods in an instance of the
principal
class (which will have been written in Objective C...whereas I'd like to
be able to write these methods in Python).

Any suggestions on an approach here?  Is there a way to load python code
which 
can replace a class which initiates the loading?  Or perhaps some way to 
dynamically extend the Objective C class in Python so that method calls
to the 
Objective C class are passed through to the Python one?  

I've been investigating the PrefPane example for hints, thinking that I
might 
be able to provide a dummy nib and use extractClasses + subclass 
from AutoBaseClass.

Perhaps there is a nice simple approach though (-;