collection metadata merging: min/max statistics handling

[soxofaan]

While checking https://github.com/openEOPlatform/architecture-docs/issues/288 issues related to stac summaries statistics, e.g. :

TypeError("Error parsing 'eo:cloud_cover' of StacSummaries: Could not parse Statistics object, actual: {'maximum': 100, 'minimum': 0}")

This implementation looks for "min" and "max" fields

openeo-aggregator/src/openeo_aggregator/metadata/models/statistics.py

Lines 14 to 52 in 804ca22

	class Statistics:
	"""By default, only ranges with a minimum and a maximum value can be specified. Ranges can be specified for ordinal
	values only, which means they need to have a rank order. Therefore, ranges can only be specified for numbers and
	some special types of strings. Examples: grades (A to F), dates or times. Implementors are free to add other derived
	statistical values to the object, for example `mean` or `stddev`.
	Attributes:
	min_ (Union[float, str]):
	max_ (Union[float, str]):
	"""
	min_: Union[float, str]
	max_: Union[float, str]
	additional_properties: Dict[str, Any] = attr.ib(init=False, factory=dict)
	def to_dict(self) -> Dict[str, Any]:
	min_: Union[float, str]
	min_ = self.min_
	max_: Union[float, str]
	max_ = self.max_
	field_dict: Dict[str, Any] = {}
	field_dict.update(self.additional_properties)
	field_dict.update(
	{
	"min": min_,
	"max": max_,
	}
	)
	return field_dict
	@classmethod
	def from_dict(cls: Type[T], src_dict: Dict[str, Any]) -> T:
	d = src_dict.copy()
	if "min" not in d or "max" not in d:

but https://github.com/radiantearth/stac-spec/blob/v1.0.0-rc.2/collection-spec/collection-spec.md#stats-object works with "minimum" and "maximum"

@JeroenVerstraelen did you get min/max from a spec, or something else? How can it be changed to minimum/maximum?

related to #76

[JeroenVerstraelen]

That requirement comes from the openeo api specification:
https://github.com/Open-EO/openeo-api/blob/master/openapi.yaml#L4467

[soxofaan]

Interesting,
@m-mohr is there an inconsistency here about stats objects as collection summaries?

• should have fields "min"/"max" according to https://github.com/Open-EO/openeo-api/blob/16b1122c7090cc4fedcabace48686a4f73c1c876/openapi.yaml#L4450-L4474
• should have fields "minimum"/"maximum" according to https://github.com/radiantearth/stac-spec/blob/v1.0.0-rc.2/collection-spec/collection-spec.md#stats-object

[m-mohr]

• min/max was used in STAC 0.9 and we based the openEO API 1.0 on this version.
• minimum/maximum was adopted somewhere in STAC 1.0 beta/rc, so both can occur depending on the STAC version implemented. I'll update to minimum/maximum in the API with the work that is going on to update to STAC 1.0.

[m-mohr]

See Open-EO/openeo-api@8a112b7