Re: media_from_site API

[Iago Toral <itoral igalia com>]

On Fri, 03 Dec 2010 12:44:01 +0100, "Juan A. Suarez Romero" 
<jasuarez igalia com> wrote:

> Sorry for being late. I know you have already proposed an
> implementation, so forget about this if you think it isn't worth.
>
>
> When I saw this feature request, I was thinking about a way of doing 
> it
> more generic.
>
> So my idea was to have a function similar to 
> grl_media_source_metadata()
> to do it.
>
> The API for the proposed function would be
>
> guint
> grl_multiple_source_inverse_metadata (const GList *sources,
>                                  GrlKeyID *field,
>                                  GValue *value,
>                                  const GList *keys,
>                                  GrlMetadataResolutionFlags flags,
>                                  GrlMediaSourceMetadataCb callback,
>                                  gpointer user_data);
>
>
> So for the case of youtube, you'd use GRL_METADATA_KEY_SITE as field 
> and
> the appropriate value. And it would return in the callback the 
> GrlMedia
> already filled with the requested keys.
>
> Each source would register which keys they support for inverse
> resolution.
>
> This would allow for future extensions if plugins can resolve medias 
> by
> other fields besides the site url.

Anything that makes this more generic and usable is ok with me, but as 
I always say, we have to be practical and not try to do super-generic 
stuff that ends up being used for just one case.

The case of the URL conversion is an obvious use case that makes sense. 
Do you have any examples where other data could be used and the url is 
not available? If you find good use cases for that I would be willing to 
go for this version, otherwise, I would postpone the idea until we have 
specific use cases that we think are reasonable and I would keep it 
simple for now.

Also, there is another issue, for the case of the url, it is not enough 
to know if the source supports conversion from the url, you also need to 
know if the source supports that url in particular (hence that 
test_media_from_site), probably this is specific for the url case 
because with other that this check would probably not make sense, so 
even in the situation of wanting a more generic approach, it could still 
make sense to have the media_from_site API as a separate option.

Iago