Add support for GeometryCollection fields

requirements-test.txt

@@ -1,3 +1,4 @@
+six
 psycopg2
 djangorestframework>=3.3
 coverage==3.7.1  # rq.filter: >=3,<4

requirements.txt

@@ -1 +1,2 @@
+six
 djangorestframework>=3.3,<3.7

rest_framework_gis/fields.py

@@ -1,3 +1,4 @@
+import six  # TODO Remove this along with GeoJsonDict when support for python 2.6/2.7 is dropped.
 import json
 from collections import OrderedDict
 
@@ -25,10 +26,7 @@ def to_representation(self, value):
         if isinstance(value, dict) or value is None:
             return value
         # we expect value to be a GEOSGeometry instance
-        return GeoJsonDict((
-            ('type', value.geom_type),
-            ('coordinates', value.coords),
-        ))
+        return GeoJsonDict(value.geojson)
 
     def to_internal_value(self, value):
         if value == '' or value is None:
@@ -54,10 +52,7 @@ def to_representation(self, value):
         value = super(GeometrySerializerMethodField, self).to_representation(value)
         if value is not None:
             # we expect value to be a GEOSGeometry instance
-            return GeoJsonDict((
-                ('type', value.geom_type),
-                ('coordinates', value.coords),
-            ))
+            return GeoJsonDict(value.geojson)
         else:
             return None
 
@@ -67,6 +62,18 @@ class GeoJsonDict(OrderedDict):
     Used for serializing GIS values to GeoJSON values
     TODO: remove this when support for python 2.6/2.7 will be dropped
     """
+    def __init__(self, *args, **kwargs):
+        """
+        If a string is passed attempt to pass it through json.loads,
+        because it should be a geojson formatted string.
+        """
+        if args and isinstance(args[0], six.string_types):
+            try:
+                geojson = json.loads(args[0])
+                args = (geojson,)
+            except ValueError:
+                pass
+        super(GeoJsonDict, self).__init__(*args, **kwargs)
 
     def __str__(self):
         """

tests/django_restframework_gis_tests/tests.py

@@ -521,7 +521,7 @@ def test_geometry_serializer_method_field(self):
         self.assertEqual(response.status_code, 200)
         self.assertEqual(response.data['properties']['name'], 'hidden geometry')
         self.assertEqual(response.data['geometry']['type'], 'Point')
-        self.assertEqual(response.data['geometry']['coordinates'], (0.0, 0.0))
+        self.assertEqual(response.data['geometry']['coordinates'], [0.0, 0.0])
 
     def test_geometry_serializer_method_field_none(self):
         location = Location.objects.create(name='None value', geometry='POINT (135.0 45.0)')
@@ -584,3 +584,57 @@ def test_pickle(self):
         pickled = pickle.dumps(geojsondict)
         restored = pickle.loads(pickled)
         self.assertEqual(restored, geojsondict)
+
+    def test_geometrycollection_geojson(self):
+        """ test geometry collection geojson behaviour """
+        location = Location.objects.create(name='geometry collection geojson test',
+                                           geometry='GEOMETRYCOLLECTION ('
+                                                    'POINT (135.0 45.0),'
+                                                    'LINESTRING (135.0 45.0,140.0 50.0,145.0 55.0),'
+                                                    'POLYGON ((135.0 45.0,140.0 50.0,145.0 55.0,135.0 45.0)))')
+        url = reverse('api_geojson_location_details', args=[location.id])
+        expected = {
+            'id': location.id,
+            'type': 'Feature',
+            'properties': {
+                'details': "http://testserver/geojson/%s/" % location.id,
+                'name': 'geometry collection geojson test',
+                'fancy_name': 'Kool geometry collection geojson test',
+                'timestamp': None,
+                'slug': 'geometry-collection-geojson-test',
+            },
+            'geometry': {
+                'type': 'GeometryCollection',
+                'geometries': [
+                    {
+                        'type': 'Point',
+                        'coordinates': [135.0, 45.0]
+                    },
+                    {
+                        'type': 'LineString',
+                        'coordinates': [
+                            [135.0, 45.0],
+                            [140.0, 50.0],
+                            [145.0, 55.0]
+                        ]
+                    },
+                    {
+                        'type': 'Polygon',
+                        'coordinates': [
+                            [
+                                [135.0, 45.0],
+                                [140.0, 50.0],
+                                [145.0, 55.0],
+                                [135.0, 45.0],
+                            ]
+                        ]
+                    },
+                ],
+            }
+        }
+        response = self.client.get(url)
+        if sys.version_info > (3, 0, 0):
+            self.assertCountEqual(json.dumps(response.data), json.dumps(expected))
+        else:
+            self.assertItemsEqual(json.dumps(response.data), json.dumps(expected))
+        self.assertContains(response, "Kool geometry collection geojson test")