[ZODB-Dev] Re: ZEO signal feature

[Toby Dickenson]

On Wednesday 25 Sep 2002 4:09 pm, Christian Reis wrote:
> On Tue, Sep 24, 2002 at 05:21:01PM +0100, Toby Dickenson wrote:
> > > This raises an interesting question for me: How would anyone invoke
> > > extension methods on the storage?  ZODB application software isn't
> > > supposed to interact with the storage directly.  It's supposed to u=
se
> > > the DB and Connection objects.
> >
> > Yes, this is only for clients that have special knowledge about the t=
ype
> > of storage they are dealing with. For example DirectoryStorage has a =
Zope
> > object which adds extra management controls for its snapshot mode.
>
> Could DB or Connection be changed to allow the client to know these
> extensions are available?

Im not sure which question you meant to ask.....

Can these extension methods be made available through the Connection or D=
B?

   It could, but I dont see any advantage. The DB already makes its
   storage available.

Could clients have a way to find out which extension methods are implemen=
ted=20
by a storage?

   My proposed definition of this method requires that unknown extensions
   raise a NotImplementedError. The easy way to see if it exists is to tr=
y
   it. For an example see:=20
<http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/dirstorage/DirectoryStora=
ge/DirectoryStorageToolkit/>