""" 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): "Ensuring exceptions are raised for operators & functions invalid on geography fields." 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 that expects 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: # SpatiaLite 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, 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_m rounded_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')