EDR Xarray covjson reordering y

[pzaborowski]

Description
in
provider/xarray_.py
gen_covjson function
following code:

minx, miny, maxx, maxy = metadata['bbox']
        mint, maxt = metadata['time']
        try:
            tmp_min = data.coords[self.y_field].values[0]
        except IndexError:
            tmp_min = data.coords[self.y_field].values
        try:
            tmp_max = data.coords[self.y_field].values[-1]
        except IndexError:
            tmp_max = data.coords[self.y_field].values

        if tmp_min > tmp_max:
            LOGGER.debug(f'Reversing direction of {self.y_field}')
            miny = tmp_max
            maxy = tmp_min
...
                    'y': {
                        'start': maxy,
                        'stop': miny,

Is reversing only axis north-south but not data. It breaks resulting coveragejson with inconsistent axis-data.
Either it shall be followed by the data reordering (not cheap so maybe not recommended) or axis start/stop shall be read from data.
Reading start/stop from data would also partly address the issue when data grid does not fill the query bbox and resulting array would not fill current axis.
Steps to Reproduce
Steps to reproduce the behavior:
Use reference configuration from https://docs.pygeoapi.io/en/latest/data-publishing/ogcapi-edr.html
View the results on the map - see it is upside down.

Expected behavior

1. Reordering of axis shall be removed or followed by data reordering - in case data is not expected organisation exception could be rised optionally.
2. start/stop of axis shall be read from data to make it consistent with variables (not bbox min/max which could make data stretched inproperly

Screenshots/Tracebacks
If applicable, add screenshots to help explain your problem.

Environment

• OS:
• Python version:
• pygeoapi version:

Additional context
Test data from https://docs.pygeoapi.io/en/latest/data-publishing/ogcapi-edr.html

• tests/data/coads_sst.nc
  looks like longitude is in fact 0-360 not as in coords -180:180

[pzaborowski]

same problem in demo deployment https://demo.pygeoapi.io/master/collections/icoads-sst/cube?bbox=-180,-90,180,90&datetime=2000-01-16%2F2000-02-01&select_properties=AIRT