Fixed #25141 -- Diminished GDAL dependence during geojson serialization (1da170a2) · Commits · Dom Sekotill / django

django/contrib/gis/geos/collections.py

+14 −0

Original line number	Diff line number	Diff line
		@@ -2,6 +2,7 @@
		This module houses the Geometry Collection objects:
		GeometryCollection, MultiPoint, MultiLineString, and MultiPolygon
		"""
		import json
		from ctypes import byref, c_int, c_uint

		from django.contrib.gis.geos import prototypes as capi
		@@ -83,6 +84,19 @@ class GeometryCollection(GEOSGeometry):
		_set_single = GEOSGeometry._set_single_rebuild
		_assign_extended_slice = GEOSGeometry._assign_extended_slice_rebuild

		@property
		def json(self):
		if self.__class__.__name__ == 'GeometryCollection':
		return json.dumps({
		'type': self.__class__.__name__,
		'geometries': [
		{'type': geom.__class__.__name__, 'coordinates': geom.coords}
		for geom in self
		],
		})
		return super(GeometryCollection, self).json
		geojson = json

		@property
		def kml(self):
		"Returns the KML for this Geometry Collection."

+3 −5

Original line number	Diff line number	Diff line
		@@ -4,6 +4,7 @@
		"""
		from __future__ import unicode_literals

		import json
		from ctypes import addressof, byref, c_double

		from django.contrib.gis import gdal
		@@ -411,12 +412,9 @@ class GEOSGeometry(GEOSBase, ListMixin):
		@property
		def json(self):
		"""
		Returns GeoJSON representation of this Geometry if GDAL is installed.
		Returns GeoJSON representation of this Geometry.
		"""
		if gdal.HAS_GDAL:
		return self.ogr.json
		else:
		raise GEOSException('GeoJSON output only supported when GDAL is installed.')
		return json.dumps({'type': self.__class__.__name__, 'coordinates': self.coords})
		geojson = json

		@property

+9 −7

Original line number	Diff line number	Diff line
		@@ -17,17 +17,14 @@ class Serializer(JSONSerializer):
		def _init_options(self):
		super(Serializer, self)._init_options()
		self.geometry_field = self.json_kwargs.pop('geometry_field', None)
		self.srs = SpatialReference(self.json_kwargs.pop('srid', 4326))
		self.srid = self.json_kwargs.pop('srid', 4326)

		def start_serialization(self):
		if not HAS_GDAL:
		# GDAL is needed for the geometry.geojson call
		raise SerializationError("The geojson serializer requires the GDAL library.")
		self._init_options()
		self._cts = {} # cache of CoordTransform's
		self.stream.write(
		'{"type": "FeatureCollection", "crs": {"type": "name", "properties": {"name": "EPSG:%d"}},'
		' "features": [' % self.srs.srid)
		' "features": [' % self.srid)

		def end_serialization(self):
		self.stream.write(']}')
		@@ -48,10 +45,15 @@ class Serializer(JSONSerializer):
		"properties": self._current,
		}
		if self._geometry:
		if self._geometry.srid != self.srs.srid:
		if self._geometry.srid != self.srid:
		# If needed, transform the geometry in the srid of the global geojson srid
		if not HAS_GDAL:
		raise SerializationError(
		'Unable to convert geometry to SRID %s when GDAL is not installed.' % self.srid
		)
		if self._geometry.srid not in self._cts:
		self._cts[self._geometry.srid] = CoordTransform(self._geometry.srs, self.srs)
		srs = SpatialReference(self.srid)
		self._cts[self._geometry.srid] = CoordTransform(self._geometry.srs, srs)
		self._geometry.transform(self._cts[self._geometry.srid])
		data["geometry"] = eval(self._geometry.geojson)
		else:

+11 −3

Original line number	Diff line number	Diff line
		@@ -7,9 +7,17 @@ GeoJSON Serializer
		.. module:: django.contrib.gis.serializers.geojson
		:synopsis: Serialization of GeoDjango models in the GeoJSON format.

		GeoDjango provides a specific serializer for the `GeoJSON`__ format. The GDAL
		library is required for this serializer. See :doc:`/topics/serialization` for
		more information on serialization.
		GeoDjango provides a specific serializer for the `GeoJSON`__ format. See
		:doc:`/topics/serialization` for more information on serialization.

		The GDAL library is required if any of the serialized geometries need
		coordinate transformations (that is if the geometry's spatial reference system
		differs from the ``srid`` serializer option).

		.. versionchanged:: 1.9

		The GeoJSON serializer no longer needs GDAL if all geometries are in the
		same coordinate system as the ``srid`` serializer option.

		__ http://geojson.org/

+10 −1

Original line number	Diff line number	Diff line
		@@ -4,7 +4,8 @@ import json

		from django.contrib.gis.geos import LinearRing, Point, Polygon
		from django.core import serializers
		from django.test import TestCase, skipUnlessDBFeature
		from django.test import TestCase, mock, skipUnlessDBFeature
		from django.utils import six

		from .models import City, MultiFields, PennsylvaniaCity

		@@ -70,6 +71,14 @@ class GeoJSONSerializerTests(TestCase):
		[int(c) for c in geodata['features'][0]['geometry']['coordinates']],
		[1564802, 5613214])

		@mock.patch('django.contrib.gis.serializers.geojson.HAS_GDAL', False)
		def test_without_gdal(self):
		# Without coordinate transformation, the serialization should succeed:
		serializers.serialize('geojson', City.objects.all())
		with six.assertRaisesRegex(self, serializers.base.SerializationError, '.*GDAL is not installed'):
		# Coordinate transformations need GDAL
		serializers.serialize('geojson', City.objects.all(), srid=2847)

		def test_deserialization_exception(self):
		"""
		GeoJSON cannot be deserialized.