Search by datetime in CQL Text

[m-mohr]

Describe the bug
As datetime is not supported directly, as seen in #100, I'm now trying to use CQL which was mentioned as alternative.

I want to filter by timestamp on the datetime field, e.g.
https://planetarycomputer.microsoft.com/api/stac/v1/collections/chloris-biomass/items?limit=12&filter-lang=cql2-text&filter=datetime < TIMESTAMP('2010-01-01T01%3A00%3A00.000Z') (also tried the URL encoded variant)

Instead of results that are older than 2010, I also get results that are newer than 2010. It looks like the filter is not taken into account at all.

Is CQL not supported on the items endpoint? Some of the conformance classes around filtering are a bit of a mess in stac-fastapi and stac-api-spec currently, so I'm just guessing...

To reproduce
See above.

Expected behavior
See above.

[jerstlouis]

In OGC Testbed 20 GeoDataCubes task, we experienced similar issues which we document in detail in an upcoming Engineering Report (OGC 24-035 GDC API Profile Engineering Report).

The issue might potentially be related to a caching mechanism which does not take query parameters into account.

We had similar results with both the filter and datetime query parameters, whereas whichever results are returned by a first request are the same results returned for any further request using different query parameters.

For example:

https://planetarycomputer.microsoft.com/api/stac/v1/collections/nasa-nex-gddp-cmip6/items?filter-lang=cql2-text&filter=cmpi6:model='GFDL-ESM4' and cmip6:scenario='ssp585'

returns scenarios other than ssp585 (e.g., ssp245)

https://planetarycomputer.microsoft.com/api/stac/v1/collections/nasa-nex-gddp-cmip6/items?datetime=2021-01-01T00:00:00Z/2021-01-31T00:00:00Z

will include years other than 2021 depending on what happens to be cached, which seems to change (as of writing this it seems to be returning 2100)

This really makes this STAC API deployment unusable.

[m-mohr]

Might be a bug/missing feature in stac-fastapi-pgstac, which was fixed/implemented just a couple of days ago. See also stac-utils/stac-fastapi-pgstac#190