"""Tests for geography support in PostGIS"""import os
from django.contrib.gis.db import models
from django.contrib.gis.db.models.functions import Area, Distance
from django.contrib.gis.measure import D
from django.db import NotSupportedError, connection
from django.db.models.functions import Cast
from django.test import TestCase, skipIfDBFeature, skipUnlessDBFeature
from ..utils import FuncTestMixin
from .models import City, County, Zipcode
class GeographyTest(TestCase):
fixtures = ["initial"]
def test01_fixture_load(self):
"Ensure geography features loaded properly."
self.assertEqual(8, City.objects.count())
@skipUnlessDBFeature("supports_distances_lookups", "supports_distance_geodetic")
def test02_distance_lookup(self):
"Testing distance lookup support on non-point geography fields."
z = Zipcode.objects.get(code="77002")
cities1 = list(City.objects.filter(point__distance_lte=(z.poly, D(mi=500)))
.order_by("name")
.values_list("name", flat=True)
)cities2 = list(City.objects.filter(point__dwithin=(z.poly, D(mi=500)))
.order_by("name")
.values_list("name", flat=True)
)for cities in [cities1, cities2]:
self.assertEqual(["Dallas", "Houston", "Oklahoma City"], cities)
def test04_invalid_operators_functions(self):
"""
Exceptions are raised for operators & functions invalid on geographyfields."""if not connection.ops.postgis:
self.skipTest("This is a PostGIS-specific test.")
# Only a subset of the geometry functions & operator are available
# to PostGIS geography types. For more information, visit:
# http://postgis.refractions.net/documentation/manual-1.5/ch08.html#PostGIS_GeographyFunctions
z = Zipcode.objects.get(code="77002")
# ST_Within not available.
with self.assertRaises(ValueError):
City.objects.filter(point__within=z.poly).count()
# `@` operator not available.
with self.assertRaises(ValueError):
City.objects.filter(point__contained=z.poly).count()
# Regression test for #14060, `~=` was never really implemented for PostGIS.
htown = City.objects.get(name="Houston")
with self.assertRaises(ValueError):
City.objects.get(point__exact=htown.point)
def test05_geography_layermapping(self):
"Testing LayerMapping support on models with geography fields."
# There is a similar test in `layermap` that uses the same data set,
# but the County model here is a bit different.
from django.contrib.gis.utils import LayerMapping
# Getting the shapefile and mapping dictionary.
shp_path = os.path.realpath(
os.path.join(os.path.dirname(__file__), "..", "data")
)co_shp = os.path.join(shp_path, "counties", "counties.shp")
co_mapping = {"name": "Name",
"state": "State",
"mpoly": "MULTIPOLYGON",
}# Reference county names, number of polygons, and state names.
names = ["Bexar", "Galveston", "Harris", "Honolulu", "Pueblo"]
num_polys = [1, 2, 1, 19, 1] # Number of polygons for each.
st_names = ["Texas", "Texas", "Texas", "Hawaii", "Colorado"]
lm = LayerMapping(County, co_shp, co_mapping, source_srs=4269, unique="name")
lm.save(silent=True, strict=True)
for c, name, num_poly, state in zip(
County.objects.order_by("name"), names, num_polys, st_names
):self.assertEqual(4326, c.mpoly.srid)
self.assertEqual(num_poly, len(c.mpoly))
self.assertEqual(name, c.name)
self.assertEqual(state, c.state)
class GeographyFunctionTests(FuncTestMixin, TestCase):
fixtures = ["initial"]
@skipUnlessDBFeature("supports_extent_aggr")
def test_cast_aggregate(self):
"""
Cast a geography to a geometry field for an aggregate function thatexpects a geometry input."""if not connection.features.supports_geography:
self.skipTest("This test needs geography support")
expected = (-96.8016128540039,
29.7633724212646,
-95.3631439208984,
32.782058715820,
)res = City.objects.filter(name__in=("Houston", "Dallas")).aggregate(
extent=models.Extent(Cast("point", models.PointField()))
)for val, exp in zip(res["extent"], expected):
self.assertAlmostEqual(exp, val, 4)
@skipUnlessDBFeature("has_Distance_function", "supports_distance_geodetic")
def test_distance_function(self):
"""
Testing Distance() support on non-point geography fields."""if connection.ops.oracle:
ref_dists = [0, 4899.68, 8081.30, 9115.15]
elif connection.ops.spatialite:
if connection.ops.spatial_version < (5,):
# SpatiaLite < 5 returns non-zero distance for polygons and points
# covered by that polygon.
ref_dists = [326.61, 4899.68, 8081.30, 9115.15]
else:
ref_dists = [0, 4899.68, 8081.30, 9115.15]
else:
ref_dists = [0, 4891.20, 8071.64, 9123.95]
htown = City.objects.get(name="Houston")
qs = Zipcode.objects.annotate(
distance=Distance("poly", htown.point),
distance2=Distance(htown.point, "poly"),
)for z, ref in zip(qs, ref_dists):
self.assertAlmostEqual(z.distance.m, ref, 2)
if connection.ops.postgis:
# PostGIS casts geography to geometry when distance2 is calculated.
ref_dists = [0, 4899.68, 8081.30, 9115.15]
for z, ref in zip(qs, ref_dists):
self.assertAlmostEqual(z.distance2.m, ref, 2)
if not connection.ops.spatialite:
# Distance function combined with a lookup.
hzip = Zipcode.objects.get(code="77002")
self.assertEqual(qs.get(distance__lte=0), hzip)
@skipUnlessDBFeature("has_Area_function", "supports_area_geodetic")
def test_geography_area(self):
"""
Testing that Area calculations work on geography columns."""# SELECT ST_Area(poly) FROM geogapp_zipcode WHERE code='77002';
z = Zipcode.objects.annotate(area=Area("poly")).get(code="77002")
# Round to the nearest thousand as possible values (depending on
# the database and geolib) include 5439084, 5439100, 5439101.
rounded_value = z.area.sq_mrounded_value -= z.area.sq_m % 1000
self.assertEqual(rounded_value, 5439000)
@skipUnlessDBFeature("has_Area_function")
@skipIfDBFeature("supports_area_geodetic")
def test_geodetic_area_raises_if_not_supported(self):
with self.assertRaisesMessage(
NotSupportedError, "Area on geodetic coordinate systems not supported."
):Zipcode.objects.annotate(area=Area("poly")).get(code="77002")