1 """

     2 Tests for geography support in PostGIS 1.5+

     3 """

     4 import os

     5 from django.contrib.gis import gdal

     6 from django.contrib.gis.measure import D

     7 from django.test import TestCase

     8 from models import City, County, Zipcode

     9 

    10 class GeographyTest(TestCase):

    11 

    12     def test01_fixture_load(self):

    13         "Ensure geography features loaded properly."

    14         self.assertEqual(8, City.objects.count())

    15 

    16     def test02_distance_lookup(self):

    17         "Testing GeoQuerySet distance lookup support on non-point geography fields."

    18         z = Zipcode.objects.get(code='77002')

    19         cities1 = list(City.objects

    20                        .filter(point__distance_lte=(z.poly, D(mi=500)))

    21                        .order_by('name')

    22                        .values_list('name', flat=True))

    23         cities2 = list(City.objects

    24                        .filter(point__dwithin=(z.poly, D(mi=500)))

    25                        .order_by('name')

    26                        .values_list('name', flat=True))

    27         for cities in [cities1, cities2]:

    28             self.assertEqual(['Dallas', 'Houston', 'Oklahoma City'], cities)

    29 

    30     def test03_distance_method(self):

    31         "Testing GeoQuerySet.distance() support on non-point geography fields."

    32         # `GeoQuerySet.distance` is not allowed geometry fields.

    33         htown = City.objects.get(name='Houston')

    34         qs = Zipcode.objects.distance(htown.point)

    35 

    36     def test04_invalid_operators_functions(self):

    37         "Ensuring exceptions are raised for operators & functions invalid on geography fields."

    38         # Only a subset of the geometry functions & operator are available

    39         # to PostGIS geography types.  For more information, visit:

    40         #  http://postgis.refractions.net/documentation/manual-1.5/ch08.html#PostGIS_GeographyFunctions

    41         z = Zipcode.objects.get(code='77002')

    42         # ST_Within not available.

    43         self.assertRaises(ValueError, City.objects.filter(point__within=z.poly).count)

    44         # `@` operator not available.

    45         self.assertRaises(ValueError, City.objects.filter(point__contained=z.poly).count)

    46 

    47     def test05_geography_layermapping(self):

    48         "Testing LayerMapping support on models with geography fields."

    49         # There is a similar test in `layermap` that uses the same data set,

    50         # but the County model here is a bit different.

    51         if not gdal.HAS_GDAL: return

    52         from django.contrib.gis.utils import LayerMapping

    53 

    54         # Getting the shapefile and mapping dictionary.

    55         shp_path = os.path.realpath(os.path.join(os.path.dirname(__file__), '..', 'data'))

    56         co_shp = os.path.join(shp_path, 'counties', 'counties.shp')

    57         co_mapping = {'name' : 'Name',

    58                       'state' : 'State',

    59                       'mpoly' : 'MULTIPOLYGON',

    60                       }

    61 

    62         # Reference county names, number of polygons, and state names.

    63         names = ['Bexar', 'Galveston', 'Harris', 'Honolulu', 'Pueblo']

    64         num_polys = [1, 2, 1, 19, 1] # Number of polygons for each.

    65         st_names = ['Texas', 'Texas', 'Texas', 'Hawaii', 'Colorado']

    66 

    67         lm = LayerMapping(County, co_shp, co_mapping, source_srs=4269, unique='name')

    68         lm.save(silent=True, strict=True)

    69 

    70         for c, name, num_poly, state in zip(County.objects.order_by('name'), names, num_polys, st_names):

    71             self.assertEqual(4326, c.mpoly.srid)

    72             self.assertEqual(num_poly, len(c.mpoly))

    73             self.assertEqual(name, c.name)

    74             self.assertEqual(state, c.state)