Re: import/export interface for Bonobo

[Dan Winship <danw helixcode com>]

> So it seems to me like the right place to put typing information might
> be the Stream interface, not PersistStream. A Stream could have an
> optional associated MIME type which the component implementing
> PersistStream could check when reading. Typing on an output stream
> could be considered purely a hint, perhaps.

That was going good until the last sentence. Remember that I need to
be able to request both text/plain and text/html from the editor. Or
by "purely a hint", do you just mean "we won't hold it against
components written to the old interfaces if they don't support this"?
I think we should require components (at least in the future) to
either obey the type or raise an exception, rather than forcing the
receiving end to check that the data is the correct type (which, as
has been pointed out, he may not be able to do).

Or does the persister just reset the type of the stream to the type he
wants it to be if he can't deal with it how it is? That feels wrong.

> With OAF you can already determine statically what mime types a
> component supports

However, it may not be able to convert between any two types that it
supports, and thus it may not always be able to export data in all of
its supported types. Of course, if there's an exception that can be
raised in this case, the receiver could just iterate through the types
it wants to try until it finds one that works. This seems like more
effort than just asking "what types can you export" though.


There's also the compound-document nature of HTML to deal with,
although maybe that's what Storages are for?

-- Dan