Extent metadata for the whole API

[PanierAvide]

Hello,

I'm currently working on a STAC API implementation for offering geolocated street pictures (docs).

I'm wondering what would be the best option regarding STAC API specification for a client to get the extent metadata (mainly spatial, but possibly temporal) of the whole data behind the API. What I thought of :

• Setting it in landing (/ route) : doesn't fit in the Catalog definition
• Setting it in collections (/collections route) : no more metadata seem allowed beyond collections and links
• Setting it in all single collections : needs quite a lot of re-processing on client-side to have full extent, it would be better if done on server
• Transform landing catalog into collection : doesn't look like it's permitted by specs ?

What are you thoughts on this ? Is there an existing way in specs to do this ? Do we need an extension for this ?

Best regards.

[philvarner]

I'd add extent to the Landing Page Catalog. It's not required by the Catalog definition, but you can always add whatever metadata you want on those objects, they're just not part of the spec standard.

We might want to consider adding extent on Catalog to the spec, too.

[m-mohr]

I'd opt for the option that the landing page can also be a Collection. This was possible in the past and I also rarely used it, but then we broke that by adding the type field to Catalogs and Collections. So I'd opt to revert this change by allowing Collections as Landing Page.

[m-mohr]

We discussed this today in the working session and think this needs another discussion in a broader group.