"""
Tests for geography support in PostGIS 1.5+
"""
import os
from django.contrib.gis import gdal
from django.contrib.gis.measure import D
from django.test import TestCase
from models import City,County,Zipcode
class GeographyTest(TestCase):
def test01_fixture_load(self):
"Ensure geography features loaded properly."
self.assertEqual(8, City.objects.count())
def test02_distance_lookup(self):
"Testing GeoQuerySet 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 test03_distance_method(self):
"Testing GeoQuerySet.distance() support on non-point geography fields."
# `GeoQuerySet.distance` is not allowed geometry fields.
htown = City.objects.get(name='Houston')
qs = Zipcode.objects.distance(htown.point)
def test04_invalid_operators_functions(self):
"Ensuring exceptions are raised for operators & functions invalid on geography fields."
# 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.
self.assertRaises(ValueError, City.objects.filter(point__within=z.poly).count)
# `@` operator not available.
self.assertRaises(ValueError, City.objects.filter(point__contained=z.poly).count)
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.
if not gdal.HAS_GDAL: return
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)
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