django/tests/gis_tests/geoapp/test_serializers.py

111 lines
4.3 KiB
Python

import json
from django.contrib.gis.geos import LinearRing, Point, Polygon
from django.core import serializers
from django.test import TestCase
from .models import City, MultiFields, PennsylvaniaCity
class GeoJSONSerializerTests(TestCase):
fixtures = ["initial"]
def test_builtin_serializers(self):
"""
'geojson' should be listed in available serializers.
"""
all_formats = set(serializers.get_serializer_formats())
public_formats = set(serializers.get_public_serializer_formats())
self.assertIn("geojson", all_formats)
self.assertIn("geojson", public_formats)
def test_serialization_base(self):
geojson = serializers.serialize("geojson", City.objects.order_by("name"))
geodata = json.loads(geojson)
self.assertEqual(len(geodata["features"]), len(City.objects.all()))
self.assertEqual(geodata["features"][0]["geometry"]["type"], "Point")
self.assertEqual(geodata["features"][0]["properties"]["name"], "Chicago")
first_city = City.objects.order_by("name").first()
self.assertEqual(geodata["features"][0]["id"], first_city.pk)
self.assertEqual(geodata["features"][0]["properties"]["pk"], str(first_city.pk))
def test_geometry_field_option(self):
"""
When a model has several geometry fields, the 'geometry_field' option
can be used to specify the field to use as the 'geometry' key.
"""
MultiFields.objects.create(
city=City.objects.first(),
name="Name",
point=Point(5, 23),
poly=Polygon(LinearRing((0, 0), (0, 5), (5, 5), (5, 0), (0, 0))),
)
geojson = serializers.serialize("geojson", MultiFields.objects.all())
geodata = json.loads(geojson)
self.assertEqual(geodata["features"][0]["geometry"]["type"], "Point")
geojson = serializers.serialize(
"geojson", MultiFields.objects.all(), geometry_field="poly"
)
geodata = json.loads(geojson)
self.assertEqual(geodata["features"][0]["geometry"]["type"], "Polygon")
# geometry_field is considered even if not in fields (#26138).
geojson = serializers.serialize(
"geojson",
MultiFields.objects.all(),
geometry_field="poly",
fields=("city",),
)
geodata = json.loads(geojson)
self.assertEqual(geodata["features"][0]["geometry"]["type"], "Polygon")
def test_id_field_option(self):
"""
By default Django uses the pk of the object as the id for a feature.
The 'id_field' option can be used to specify a different field to use
as the id.
"""
cities = City.objects.order_by("name")
geojson = serializers.serialize("geojson", cities, id_field="name")
geodata = json.loads(geojson)
self.assertEqual(geodata["features"][0]["id"], cities[0].name)
def test_fields_option(self):
"""
The fields option allows to define a subset of fields to be present in
the 'properties' of the generated output.
"""
PennsylvaniaCity.objects.create(
name="Mansfield", county="Tioga", point="POINT(-77.071445 41.823881)"
)
geojson = serializers.serialize(
"geojson",
PennsylvaniaCity.objects.all(),
fields=("county", "point"),
)
geodata = json.loads(geojson)
self.assertIn("county", geodata["features"][0]["properties"])
self.assertNotIn("founded", geodata["features"][0]["properties"])
self.assertNotIn("pk", geodata["features"][0]["properties"])
def test_srid_option(self):
geojson = serializers.serialize(
"geojson", City.objects.order_by("name"), srid=2847
)
geodata = json.loads(geojson)
coordinates = geodata["features"][0]["geometry"]["coordinates"]
# Different PROJ versions use different transformations, all are
# correct as having a 1 meter accuracy.
self.assertAlmostEqual(coordinates[0], 1564802, -1)
self.assertAlmostEqual(coordinates[1], 5613214, -1)
def test_deserialization_exception(self):
"""
GeoJSON cannot be deserialized.
"""
with self.assertRaises(serializers.base.SerializerDoesNotExist):
serializers.deserialize("geojson", "{}")