Re: [Tracker] RDF Queries

[Michael Lissner <mlissner michaeljaylissner com>]

Cool. Some responses below, though I still haven't gotten the query to 
work... :)

Martyn Russell wrote:
> Michael Lissner wrote:
> > Huh. I played with this a bit more today, and it was giving me errors:
> >
> > executing rdf query <rdfq:Condition>
> >    <rdfq:equals>
> >        <rdfq:Property name='Audio:Album' />
> >        <rdf:String>Plans</rdf:String>
> >    </rdfq:equals>
> > </rdfq:Condition>
>
> This works for me, perhaps you are calling the API with something that 
> causes errors.
>
> This is how I call it:
>
>     tracker_search_query_async (priv->client,
>                     time (NULL),
>                     instance->service_type,
>                     NULL, /* Fields */
>                     NULL, /* Search text */
>                     NULL, /* Keywords */
>                     instance->rdf_query,
>                     instance->current_pos,
>                     ELEMENTS_PER_QUERY,
>                     FALSE, /* Sort by service */
>                     instance->sort_fields,
>                     FALSE, /* Sort descending */
>                     query_get_data_cb,
>                     instance);
>
> Are you calling this function, if so, how?
I'm simply using the terminal to call: tracker-query queryFile.rdf. I 
don't know the function that you're mentioning above. I'm guessing it's 
from the source code?
> > I also ran tracker-extract on the mp3 file that I was expecting to 
> > get a hit from, and it didn't return any meta data. I'm guessing that 
> > means that tracker isn't gathering meta data from music files? If 
> > that's true, is it possible to change the config so it will?
>
> This depends on a few things:
>
> 1. What extractors are supported - configure should give you a summary 
> of that.
Can you explain how to check that? I'm just running stock Ubuntu...
> 2. The MP3 itself. What exactly does tracker-extract output for that 
> file if you use:
>
>  /usr/libexec/tracker-extract -v 3 -f /path/to/filename
Well, my version of tracker-extract throws an error when I give it those 
arguments. It doesn't seem to have a -v argument, nor a -f argument. 
When I run it without those, it extracts nothing at all...suspicious, 
eh? Assuming tracker isn't indexing this info, is there a way to make it?

Mike