Re: Making extensions available to multiple GRE applications

Benjamin Smedberg wrote:
> I have filed and taken several bugs having to do with extensions and the 
> GRE, and I would like to outline my plans for GRE extensions (and 
> extensions in general) so that people may comment. Please reply to 
> n.p.m.xpinstall, and not to the bugs, unless you have a patch or 
> implementation comment. The overarching bug is bug 209439.
> 
> Definitions:
> "extension" == a browser addon or utility (installed with XPInstall)
> 
> My plan has the following goals:
> 
> 1) allow extensions to be registered with a GRE, so that they can be 
> made available to multiple applications using the GRE
> 2) allow extensions to be installed into their own directories, instead 
> of being installed in the same directory as an application
> 3) allow extensions (which use only frozen interfaces) to work with 
> multiple versions of the GRE
> 4) allow extensions to be un-installed
> 
> Currently, extensions "piggyback" on top of an application's chrome and 
> components directories. This makes it difficult/impossible to un-install 
> extensions. Instead, it should not be difficult for extensions to 
> maintain their own chrome and components locations.
> 
> Implementation-prerequisites:
> 1) The chrome: service needs to be extended to register arbitrary chrome 
> directories (bug 210838)
> 
> Implementation:
> Each extension would have an RDF file describing itself. The GRE would 
> include an nsIExtensionManager service, which would allow applications 
> to enumerate/discover available extensions, register extensions, and 
> enable/disable extensions as necessary. The GRE would not contain any UI 
> for extensions; any UI would be managed by applications. There would 
> also be a little command-line utility with the GRE that would register 
> extensions.
> 
> Extensions would not be enabled by default; instead, after the 
> application initializes the GRE, it would need to use the 
> nsIExtensionManager to enable the extensions that it wished to use.
> 
> Although every extension could use this mechanism, extensions meant for 
> multiple applications would benefit most from this scheme. Some 
> important examples would include:
> DOM Inspector
> Venkman
> JSLib
> tranformiix
> 
> I feel that GRE extensions are necessary, in order for the new roadmap 
> to be implemented effectively.
> 
> --BDS
> 
> P.S. Can I also argue that there ought to be a second alpha before 
> 1.5beta? Not much of the current roadmap has been completed yet, and 
> we're going to freeze 1.5a on Wednesday... how about another month and 
> then 1.5a2?
> 

Hyatt wrote something about changing the extension interface in Firebird 
(http://weblogs.mozillazine.org/dave/archives/2003_06.html#003557), he 
also got a lot of comments.
You should really coordinate your work with him so that Firebird don't 
get one implementation and GRE a different one. Actually, you should 
decide where it is best to keep different extensions before going any 
further.

--
Kjetil W.