add stac search helper methods

stac_pydantic/api/search.py

@@ -8,6 +8,7 @@
     MultiPolygon,
     Point,
     Polygon,
+    _GeometryBase,
 )
 from pydantic import BaseModel, Field, validator
 
@@ -87,3 +88,25 @@ def validate_datetime(cls, v):
                     "Invalid datetime range, must match format (begin_date, end_date)"
                 )
         return v
+
+    @property
+    def spatial_filter(self) -> Optional[_GeometryBase]:
+        """Return a geojson-pydantic object representing the spatial filter for the search request.
+
+        Check for both because the ``bbox`` and ``intersects`` parameters are mutually exclusive.
+        """
+        if self.bbox:
+            return Polygon(
+                coordinates=[
+                    [
+                        [self.bbox[0], self.bbox[3]],
+                        [self.bbox[2], self.bbox[3]],
+                        [self.bbox[2], self.bbox[1]],
+                        [self.bbox[0], self.bbox[1]],
+                        [self.bbox[0], self.bbox[3]],
+                    ]
+                ]
+            )
+        if self.intersects:
+            return self.intersects
+        return

tests/test_api_extensions.py

@@ -1,10 +1,10 @@
 from datetime import datetime
 
-import pytest
-from shapely.geometry import Polygon
+from shapely.geometry import Polygon, shape
 
 from stac_pydantic import Item
 from stac_pydantic.api.extensions.fields import FieldsExtension
+from stac_pydantic.api.search import Search
 
 
 def test_fields_filter():
@@ -29,3 +29,10 @@ def test_fields_filter():
 
     assert not props.get("bar")
     assert not d
+
+
+def test_search_geometry_bbox():
+    search = Search(collections=["foo", "bar"], bbox=[0, 0, 1, 1])
+    geom1 = shape(search.spatial_filter)
+    geom2 = Polygon.from_bounds(*search.bbox)
+    assert (geom1.intersection(geom2).area / geom1.union(geom2).area) == 1.0