cql2-json: {"bbox": ...} literals scramble axes through values.Envelope field order

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Assessment

Difficulty
2/5
Estimated time
1-3 hours
Newbie friendliness
86/100
Issue type
Bug
Clarity
Clearly specified
Activity status
Active
Tech stack
python, sqlalchemy
Domain
api, backend

Research direction

Start in parsers/cql2_json/parser.py at the BBox construction on lines 78-79, then compare its field ordering with the cql2-text parser and the SQLAlchemy backend's envelope handler. Verify the example New York bbox through parse_bbox; done means GeoJSON [minx, miny, maxx, maxy] becomes Envelope(minx, maxx, miny, maxy) without axis scrambling.

Written by the indexing model from the issue text.

Description

parsers/cql2_json/parser.py builds a BBox literal with values.Envelope(*node["bbox"]):

https://github.com/geopython/pygeofilter/blob/master/pygeofilter/parsers/cql2_json/parser.py#L78-L79

A GeoJSON-order bbox [minx, miny, maxx, maxy] therefore lands in Envelope(x1, x2, y1, y2) as x1=minx, x2=miny, y1=maxx, y2=maxy.

Since #147, the convention used by the cql2-text parser and the SQLAlchemy backend is x1=minx, x2=maxx, y1=miny, y2=maxy (the backend's envelope handler passes [x1, y1, x2, y2] to parse_bbox, and #147's test expects Envelope(-180, 180, -90, 90) for the global box). Through that convention the JSON construction mixes longitudes and latitudes.

Concrete effect via the SQLAlchemy backend: for {"bbox": [-74.1, 40.5, -73.9, 41.0]} (a ~20 km box over New York) the backend's envelope handler hands [x1, y1, x2, y2] = [-74.1, -73.9, 40.5, 41.0] to parse_bbox, which renders a polygon spanning x from -74.1 to 40.5 and y from -73.9 to 41.0 (roughly 114 by 115 degrees), so S_INTERSECTS silently matches a large part of the hemisphere rather than erroring.

Expected: Envelope(minx, maxx, miny, maxy), i.e. values.Envelope(b[0], b[2], b[1], b[3]).

Found while wiring pygeofilter 0.4.0 into an OGC API Features Part 3 endpoint; we currently rewrite {"bbox": ...} nodes to explicit GeoJSON Polygons before parsing to avoid the scramble.

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