tests: Improve spatial filter reliability and add tests

- Add new tests for spatial filters (near, distance_lt, bounds) in
  src/sa_api_v2/tests/test_spatial_views.py.
- Fix GEOSException import and handling in to_geom utility to
  gracefully handle invalid geometry strings.
- Improve error handling for bounding box filters in LocatedResourceMixin
  to return 400 Bad Request instead of 500 when provided with invalid inputs.
- Explicitly set SRID 4326 for bounding box polygons to ensure
  consistency with database queries.

Author: mjumbewu

src/sa_api_v2/tests/test_spatial_views.py

@@ -0,0 +1,126 @@
+from django.test import TestCase
+from django.test.client import RequestFactory
+from django.urls import reverse
+from django.conf import settings
+from sa_api_v2.models import User, DataSet, Place
+from sa_api_v2.views import PlaceListView
+import json
+
+class APITestMixin(object):
+    def assertStatusCode(self, response, *expected):
+        self.assertIn(response.status_code, expected,
+            'Status code not in %s response: (%s) %s' %
+            (expected, response.status_code, response.rendered_content))
+
+class TestSpatialViews(APITestMixin, TestCase):
+    def setUp(self):
+        self.owner = User.objects.create_user(username='aaron', password='123', email='abc@example.com')
+        self.dataset = DataSet.objects.create(slug='ds', owner=self.owner)
+        self.factory = RequestFactory()
+
+        # Create base path for place list
+        self.request_kwargs = {
+            'owner_username': self.owner.username,
+            'dataset_slug': self.dataset.slug
+        }
+        self.path = reverse('place-list', kwargs=self.request_kwargs)
+        self.view = PlaceListView.as_view()
+
+        # Create some places at specific coordinates
+        # (0,0), (10,0), (20,0), (30,0)
+        self.p1 = Place.objects.create(dataset=self.dataset, geometry='POINT(0 0)', data=json.dumps({'name': 1}))
+        self.p2 = Place.objects.create(dataset=self.dataset, geometry='POINT(10 0)', data=json.dumps({'name': 2}))
+        self.p3 = Place.objects.create(dataset=self.dataset, geometry='POINT(20 0)', data=json.dumps({'name': 3}))
+        self.p4 = Place.objects.create(dataset=self.dataset, geometry='POINT(30 0)', data=json.dumps({'name': 4}))
+
+    def test_GET_near_valid(self):
+        """GET with valid 'near' param should sort by distance."""
+        # Request near (0, 0)
+        request = self.factory.get(self.path + '?near=0,0')
+        response = self.view(request, **self.request_kwargs)
+
+        self.assertStatusCode(response, 200)
+        data = json.loads(response.rendered_content)
+
+        # Should be ordered 1, 2, 3, 4
+        self.assertEqual(len(data['features']), 4)
+        names = [f['properties']['name'] for f in data['features']]
+        self.assertEqual(names, [1, 2, 3, 4])
+
+        # Request near (30, 0). to_geom expects "lat, lng".
+        # So we pass "0, 30" (Lat 0, Lon 30).
+        request = self.factory.get(self.path + '?near=0,30')
+        response = self.view(request, **self.request_kwargs)
+
+        self.assertStatusCode(response, 200)
+        data = json.loads(response.rendered_content)
+
+        # Should be ordered 4, 3, 2, 1
+        names = [f['properties']['name'] for f in data['features']]
+        self.assertEqual(names, [4, 3, 2, 1])
+
+    def test_GET_near_invalid(self):
+        """GET with invalid 'near' param should return 400."""
+        # Invalid format (not enough coords)
+        request = self.factory.get(self.path + '?near=0')
+        response = self.view(request, **self.request_kwargs)
+        self.assertStatusCode(response, 400)
+
+        # Invalid format (non-numeric)
+        request = self.factory.get(self.path + '?near=foo,bar')
+        response = self.view(request, **self.request_kwargs)
+        self.assertStatusCode(response, 400)
+
+    def test_GET_bbox_valid(self):
+        """GET with valid 'bbox' param should filter places."""
+        # Approx bounding box around (9, -1) to (21, 1) -> Should catch 2 (10,0) and 3 (20,0)
+        # Bbox format: min_lon,min_lat,max_lon,max_lat
+        request = self.factory.get(self.path + '?bounds=9,-1,21,1')
+        response = self.view(request, **self.request_kwargs)
+
+        self.assertStatusCode(response, 200)
+        data = json.loads(response.rendered_content)
+
+        self.assertEqual(len(data['features']), 2)
+        names = sorted([f['properties']['name'] for f in data['features']])
+        self.assertEqual(names, [2, 3])
+
+    def test_GET_bbox_invalid(self):
+        """GET with invalid 'bounds' param should return 400."""
+        # Not enough coords
+        request = self.factory.get(self.path + '?bounds=0,0,10')
+        response = self.view(request, **self.request_kwargs)
+        self.assertStatusCode(response, 400)
+
+        # Non-numeric
+        request = self.factory.get(self.path + '?bounds=a,b,c,d')
+        response = self.view(request, **self.request_kwargs)
+        self.assertStatusCode(response, 400)
+
+    def test_GET_distance_valid(self):
+        """GET with 'distance' param should filter results by distance from 'near'."""
+        # Near (0,0), distance 1500km.
+        # Places at 0 degrees (0km) and 10 degrees (~1111km).
+        # Place at 20 degrees (~2222km) should be excluded.
+        request = self.factory.get(self.path + '?near=0,0&distance_lt=1500km')
+        response = self.view(request, **self.request_kwargs)
+
+        self.assertStatusCode(response, 200)
+        data = json.loads(response.rendered_content)
+
+        names = sorted([f['properties']['name'] for f in data['features']])
+        # Should include 1 (0,0) and 2 (10,0)
+        self.assertEqual(names, [1, 2])
+
+    def test_GET_distance_missing_near(self):
+        """GET with 'distance' but missing 'near' should return 400."""
+        request = self.factory.get(self.path + '?distance_lt=10')
+        response = self.view(request, **self.request_kwargs)
+        # The view raises QueryError, which usually maps to 400.
+        self.assertStatusCode(response, 400)
+
+    def test_GET_distance_invalid(self):
+        """GET with invalid 'distance' param should return 400."""
+        request = self.factory.get(self.path + '?near=0,0&distance_lt=invalid')
+        response = self.view(request, **self.request_kwargs)
+        self.assertStatusCode(response, 400)

src/sa_api_v2/utils.py

@@ -4,6 +4,10 @@
 if settings.USE_GEODB:
     from django.contrib.gis.geos import GEOSGeometry, Point
     from django.contrib.gis.measure import D
+    from django.contrib.gis.geos.error import GEOSException
+else:
+    class GEOSException(Exception): pass
+
 from functools import wraps
 
 try:
@@ -43,7 +47,7 @@ def to_geom(string):
     """
     try:
         geom = GEOSGeometry(string)
-    except ValueError:
+    except (ValueError, GEOSException):
         try:
             lat, lng = [float(coord.strip()) for coord in string.split(',')]
         except ValueError:

src/sa_api_v2/views/base_views.py

@@ -534,7 +534,12 @@ def get_queryset(self):
             if len(bounds) != 4:
                 raise QueryError(detail='Invalid parameter for "%s": %r' % (BBOX_PARAM, self.request.GET[BBOX_PARAM]))
 
-            boundingbox = Polygon.from_bbox(bounds)
+            try:
+                boundingbox = Polygon.from_bbox(bounds)
+                boundingbox.srid = 4326
+            except ValueError:
+                raise QueryError(detail='Invalid parameter for "%s": %r' % (BBOX_PARAM, self.request.GET[BBOX_PARAM]))
+
             queryset = queryset.filter(geometry__within=boundingbox)
 
         return queryset