1 import os, unittest

     2 from decimal import Decimal

     3 

     4 from django.db.models import Q

     5 from django.contrib.gis.gdal import DataSource

     6 from django.contrib.gis.geos import GEOSGeometry, Point, LineString

     7 from django.contrib.gis.measure import D # alias for Distance

     8 from django.contrib.gis.tests.utils import oracle, postgis, spatialite, no_oracle, no_spatialite

     9 

    10 from models import AustraliaCity, Interstate, SouthTexasInterstate, \

    11     SouthTexasCity, SouthTexasCityFt, CensusZipcode, SouthTexasZipcode

    12 from data import au_cities, interstates, stx_interstates, stx_cities, stx_zips

    13 

    14 class DistanceTest(unittest.TestCase):

    15 

    16     # A point we are testing distances with -- using a WGS84

    17     # coordinate that'll be implicitly transormed to that to

    18     # the coordinate system of the field, EPSG:32140 (Texas South Central

    19     # w/units in meters)

    20     stx_pnt = GEOSGeometry('POINT (-95.370401017314293 29.704867409475465)', 4326)

    21     # Another one for Australia

    22     au_pnt = GEOSGeometry('POINT (150.791 -34.4919)', 4326)

    23 

    24     def get_names(self, qs):

    25         cities = [c.name for c in qs]

    26         cities.sort()

    27         return cities

    28 

    29     def test01_init(self):

    30         "Initialization of distance models."

    31 

    32         # Loading up the cities.

    33         def load_cities(city_model, data_tup):

    34             for name, x, y in data_tup:

    35                 city_model(name=name, point=Point(x, y, srid=4326)).save()

    36 

    37         def load_interstates(imodel, data_tup):

    38             for name, wkt in data_tup:

    39                 imodel(name=name, path=wkt).save()

    40 

    41         load_cities(SouthTexasCity, stx_cities)

    42         load_cities(SouthTexasCityFt, stx_cities)

    43         load_cities(AustraliaCity, au_cities)

    44 

    45         self.assertEqual(9, SouthTexasCity.objects.count())

    46         self.assertEqual(9, SouthTexasCityFt.objects.count())

    47         self.assertEqual(11, AustraliaCity.objects.count())

    48 

    49         # Loading up the South Texas Zip Codes.

    50         for name, wkt in stx_zips:

    51             poly = GEOSGeometry(wkt, srid=4269)

    52             SouthTexasZipcode(name=name, poly=poly).save()

    53             CensusZipcode(name=name, poly=poly).save()

    54         self.assertEqual(4, SouthTexasZipcode.objects.count())

    55         self.assertEqual(4, CensusZipcode.objects.count())

    56 

    57         # Loading up the Interstates.

    58         load_interstates(Interstate, interstates)

    59         load_interstates(SouthTexasInterstate, stx_interstates)

    60 

    61         self.assertEqual(1, Interstate.objects.count())

    62         self.assertEqual(1, SouthTexasInterstate.objects.count())

    63 

    64     @no_spatialite

    65     def test02_dwithin(self):

    66         "Testing the `dwithin` lookup type."

    67         # Distances -- all should be equal (except for the

    68         # degree/meter pair in au_cities, that's somewhat

    69         # approximate).

    70         tx_dists = [(7000, 22965.83), D(km=7), D(mi=4.349)]

    71         au_dists = [(0.5, 32000), D(km=32), D(mi=19.884)]

    72 

    73         # Expected cities for Australia and Texas.

    74         tx_cities = ['Downtown Houston', 'Southside Place']

    75         au_cities = ['Mittagong', 'Shellharbour', 'Thirroul', 'Wollongong']

    76 

    77         # Performing distance queries on two projected coordinate systems one

    78         # with units in meters and the other in units of U.S. survey feet.

    79         for dist in tx_dists:

    80             if isinstance(dist, tuple): dist1, dist2 = dist

    81             else: dist1 = dist2 = dist

    82             qs1 = SouthTexasCity.objects.filter(point__dwithin=(self.stx_pnt, dist1))

    83             qs2 = SouthTexasCityFt.objects.filter(point__dwithin=(self.stx_pnt, dist2))

    84             for qs in qs1, qs2:

    85                 self.assertEqual(tx_cities, self.get_names(qs))

    86 

    87         # Now performing the `dwithin` queries on a geodetic coordinate system.

    88         for dist in au_dists:

    89             if isinstance(dist, D) and not oracle: type_error = True

    90             else: type_error = False

    91 

    92             if isinstance(dist, tuple):

    93                 if oracle: dist = dist[1]

    94                 else: dist = dist[0]

    95 

    96             # Creating the query set.

    97             qs = AustraliaCity.objects.order_by('name')

    98             if type_error:

    99                 # A TypeError should be raised on PostGIS when trying to pass

   100                 # Distance objects into a DWithin query using a geodetic field.

   101                 self.assertRaises(TypeError, AustraliaCity.objects.filter, point__dwithin=(self.au_pnt, dist))

   102             else:

   103                 self.assertEqual(au_cities, self.get_names(qs.filter(point__dwithin=(self.au_pnt, dist))))

   104 

   105     def test03a_distance_method(self):

   106         "Testing the `distance` GeoQuerySet method on projected coordinate systems."

   107         # The point for La Grange, TX

   108         lagrange = GEOSGeometry('POINT(-96.876369 29.905320)', 4326)

   109         # Reference distances in feet and in meters. Got these values from

   110         # using the provided raw SQL statements.

   111         #  SELECT ST_Distance(point, ST_Transform(ST_GeomFromText('POINT(-96.876369 29.905320)', 4326), 32140)) FROM distapp_southtexascity;

   112         m_distances = [147075.069813, 139630.198056, 140888.552826,

   113                        138809.684197, 158309.246259, 212183.594374,

   114                        70870.188967, 165337.758878, 139196.085105]

   115         #  SELECT ST_Distance(point, ST_Transform(ST_GeomFromText('POINT(-96.876369 29.905320)', 4326), 2278)) FROM distapp_southtexascityft;

   116         # Oracle 11 thinks this is not a projected coordinate system, so it's s

   117         # not tested.

   118         ft_distances = [482528.79154625, 458103.408123001, 462231.860397575,

   119                         455411.438904354, 519386.252102563, 696139.009211594,

   120                         232513.278304279, 542445.630586414, 456679.155883207]

   121 

   122         # Testing using different variations of parameters and using models

   123         # with different projected coordinate systems.

   124         dist1 = SouthTexasCity.objects.distance(lagrange, field_name='point')

   125         dist2 = SouthTexasCity.objects.distance(lagrange)  # Using GEOSGeometry parameter

   126         if spatialite or oracle:

   127             dist_qs = [dist1, dist2]

   128         else:

   129             dist3 = SouthTexasCityFt.objects.distance(lagrange.ewkt) # Using EWKT string parameter.

   130             dist4 = SouthTexasCityFt.objects.distance(lagrange)

   131             dist_qs = [dist1, dist2, dist3, dist4]

   132 

   133         # Original query done on PostGIS, have to adjust AlmostEqual tolerance

   134         # for Oracle.

   135         if oracle: tol = 2

   136         else: tol = 5

   137 

   138         # Ensuring expected distances are returned for each distance queryset.

   139         for qs in dist_qs:

   140             for i, c in enumerate(qs):

   141                 self.assertAlmostEqual(m_distances[i], c.distance.m, tol)

   142                 self.assertAlmostEqual(ft_distances[i], c.distance.survey_ft, tol)

   143 

   144     @no_spatialite

   145     def test03b_distance_method(self):

   146         "Testing the `distance` GeoQuerySet method on geodetic coordnate systems."

   147         if oracle: tol = 2

   148         else: tol = 5

   149 

   150         # Now testing geodetic distance aggregation.

   151         hillsdale = AustraliaCity.objects.get(name='Hillsdale')

   152         if not oracle:

   153             # PostGIS is limited to disance queries only to/from point geometries,

   154             # ensuring a TypeError is raised if something else is put in.

   155             self.assertRaises(ValueError, AustraliaCity.objects.distance, 'LINESTRING(0 0, 1 1)')

   156             self.assertRaises(ValueError, AustraliaCity.objects.distance, LineString((0, 0), (1, 1)))

   157 

   158         # Got the reference distances using the raw SQL statements:

   159         #  SELECT ST_distance_spheroid(point, ST_GeomFromText('POINT(151.231341 -33.952685)', 4326), 'SPHEROID["WGS 84",6378137.0,298.257223563]') FROM distapp_australiacity WHERE (NOT (id = 11));

   160         spheroid_distances = [60504.0628825298, 77023.948962654, 49154.8867507115, 90847.435881812, 217402.811862568, 709599.234619957, 640011.483583758, 7772.00667666425, 1047861.7859506, 1165126.55237647]

   161         #  SELECT ST_distance_sphere(point, ST_GeomFromText('POINT(151.231341 -33.952685)', 4326)) FROM distapp_australiacity WHERE (NOT (id = 11));  st_distance_sphere

   162         sphere_distances = [60580.7612632291, 77143.7785056615, 49199.2725132184, 90804.4414289463, 217712.63666124, 709131.691061906, 639825.959074112, 7786.80274606706, 1049200.46122281, 1162619.7297006]

   163 

   164         # Testing with spheroid distances first.

   165         qs = AustraliaCity.objects.exclude(id=hillsdale.id).distance(hillsdale.point, spheroid=True)

   166         for i, c in enumerate(qs):

   167             self.assertAlmostEqual(spheroid_distances[i], c.distance.m, tol)

   168         if postgis:

   169             # PostGIS uses sphere-only distances by default, testing these as well.

   170             qs =  AustraliaCity.objects.exclude(id=hillsdale.id).distance(hillsdale.point)

   171             for i, c in enumerate(qs):

   172                 self.assertAlmostEqual(sphere_distances[i], c.distance.m, tol)

   173 

   174     @no_oracle # Oracle already handles geographic distance calculation.

   175     def test03c_distance_method(self):

   176         "Testing the `distance` GeoQuerySet method used with `transform` on a geographic field."

   177         # Normally you can't compute distances from a geometry field

   178         # that is not a PointField (on PostGIS).

   179         self.assertRaises(ValueError, CensusZipcode.objects.distance, self.stx_pnt)

   180 

   181         # We'll be using a Polygon (created by buffering the centroid

   182         # of 77005 to 100m) -- which aren't allowed in geographic distance

   183         # queries normally, however our field has been transformed to

   184         # a non-geographic system.

   185         z = SouthTexasZipcode.objects.get(name='77005')

   186 

   187         # Reference query:

   188         # SELECT ST_Distance(ST_Transform("distapp_censuszipcode"."poly", 32140), ST_GeomFromText('<buffer_wkt>', 32140)) FROM "distapp_censuszipcode";

   189         dists_m = [3553.30384972258, 1243.18391525602, 2186.15439472242]

   190 

   191         # Having our buffer in the SRID of the transformation and of the field

   192         # -- should get the same results. The first buffer has no need for

   193         # transformation SQL because it is the same SRID as what was given

   194         # to `transform()`.  The second buffer will need to be transformed,

   195         # however.

   196         buf1 = z.poly.centroid.buffer(100)

   197         buf2 = buf1.transform(4269, clone=True)

   198         ref_zips = ['77002', '77025', '77401']

   199 

   200         for buf in [buf1, buf2]:

   201             qs = CensusZipcode.objects.exclude(name='77005').transform(32140).distance(buf)

   202             self.assertEqual(ref_zips, self.get_names(qs))

   203             for i, z in enumerate(qs):

   204                 self.assertAlmostEqual(z.distance.m, dists_m[i], 5)

   205 

   206     def test04_distance_lookups(self):

   207         "Testing the `distance_lt`, `distance_gt`, `distance_lte`, and `distance_gte` lookup types."

   208         # Retrieving the cities within a 20km 'donut' w/a 7km radius 'hole'

   209         # (thus, Houston and Southside place will be excluded as tested in

   210         # the `test02_dwithin` above).

   211         qs1 = SouthTexasCity.objects.filter(point__distance_gte=(self.stx_pnt, D(km=7))).filter(point__distance_lte=(self.stx_pnt, D(km=20)))

   212 

   213         # Can't determine the units on SpatiaLite from PROJ.4 string, and

   214         # Oracle 11 incorrectly thinks it is not projected.

   215         if spatialite or oracle:

   216             dist_qs = (qs1,)

   217         else:

   218             qs2 = SouthTexasCityFt.objects.filter(point__distance_gte=(self.stx_pnt, D(km=7))).filter(point__distance_lte=(self.stx_pnt, D(km=20)))

   219             dist_qs = (qs1, qs2)

   220 

   221         for qs in dist_qs:

   222             cities = self.get_names(qs)

   223             self.assertEqual(cities, ['Bellaire', 'Pearland', 'West University Place'])

   224 

   225         # Doing a distance query using Polygons instead of a Point.

   226         z = SouthTexasZipcode.objects.get(name='77005')

   227         qs = SouthTexasZipcode.objects.exclude(name='77005').filter(poly__distance_lte=(z.poly, D(m=275)))

   228         self.assertEqual(['77025', '77401'], self.get_names(qs))

   229         # If we add a little more distance 77002 should be included.

   230         qs = SouthTexasZipcode.objects.exclude(name='77005').filter(poly__distance_lte=(z.poly, D(m=300)))

   231         self.assertEqual(['77002', '77025', '77401'], self.get_names(qs))

   232 

   233     @no_spatialite

   234     def test05_geodetic_distance_lookups(self):

   235         "Testing distance lookups on geodetic coordinate systems."

   236         if not oracle:

   237             # Oracle doesn't have this limitation -- PostGIS only allows geodetic

   238             # distance queries from Points to PointFields.

   239             mp = GEOSGeometry('MULTIPOINT(0 0, 5 23)')

   240             self.assertRaises(TypeError,

   241                               AustraliaCity.objects.filter(point__distance_lte=(mp, D(km=100))))

   242             # Too many params (4 in this case) should raise a ValueError.

   243             self.assertRaises(ValueError,

   244                               AustraliaCity.objects.filter, point__distance_lte=('POINT(5 23)', D(km=100), 'spheroid', '4'))

   245 

   246         # Not enough params should raise a ValueError.

   247         self.assertRaises(ValueError,

   248                           AustraliaCity.objects.filter, point__distance_lte=('POINT(5 23)',))

   249 

   250         # Getting all cities w/in 550 miles of Hobart.

   251         hobart = AustraliaCity.objects.get(name='Hobart')

   252         qs = AustraliaCity.objects.exclude(name='Hobart').filter(point__distance_lte=(hobart.point, D(mi=550)))

   253         cities = self.get_names(qs)

   254         self.assertEqual(cities, ['Batemans Bay', 'Canberra', 'Melbourne'])

   255 

   256         # Cities that are either really close or really far from Wollongong --

   257         # and using different units of distance.

   258         wollongong = AustraliaCity.objects.get(name='Wollongong')

   259         d1, d2 = D(yd=19500), D(nm=400) # Yards (~17km) & Nautical miles.

   260 

   261         # Normal geodetic distance lookup (uses `distance_sphere` on PostGIS.

   262         gq1 = Q(point__distance_lte=(wollongong.point, d1))

   263         gq2 = Q(point__distance_gte=(wollongong.point, d2))

   264         qs1 = AustraliaCity.objects.exclude(name='Wollongong').filter(gq1 | gq2)

   265 

   266         # Geodetic distance lookup but telling GeoDjango to use `distance_spheroid`

   267         # instead (we should get the same results b/c accuracy variance won't matter

   268         # in this test case).

   269         if postgis:

   270             gq3 = Q(point__distance_lte=(wollongong.point, d1, 'spheroid'))

   271             gq4 = Q(point__distance_gte=(wollongong.point, d2, 'spheroid'))

   272             qs2 = AustraliaCity.objects.exclude(name='Wollongong').filter(gq3 | gq4)

   273             querysets = [qs1, qs2]

   274         else:

   275             querysets = [qs1]

   276 

   277         for qs in querysets:

   278             cities = self.get_names(qs)

   279             self.assertEqual(cities, ['Adelaide', 'Hobart', 'Shellharbour', 'Thirroul'])

   280 

   281     def test06_area(self):

   282         "Testing the `area` GeoQuerySet method."

   283         # Reference queries:

   284         # SELECT ST_Area(poly) FROM distapp_southtexaszipcode;

   285         area_sq_m = [5437908.90234375, 10183031.4389648, 11254471.0073242, 9881708.91772461]

   286         # Tolerance has to be lower for Oracle and differences

   287         # with GEOS 3.0.0RC4

   288         tol = 2

   289         for i, z in enumerate(SouthTexasZipcode.objects.area()):

   290             self.assertAlmostEqual(area_sq_m[i], z.area.sq_m, tol)

   291 

   292     def test07_length(self):

   293         "Testing the `length` GeoQuerySet method."

   294         # Reference query (should use `length_spheroid`).

   295         # SELECT ST_length_spheroid(ST_GeomFromText('<wkt>', 4326) 'SPHEROID["WGS 84",6378137,298.257223563, AUTHORITY["EPSG","7030"]]');

   296         len_m1 = 473504.769553813

   297         len_m2 = 4617.668

   298 

   299         if spatialite:

   300             # Does not support geodetic coordinate systems.

   301             self.assertRaises(ValueError, Interstate.objects.length)

   302         else:

   303             qs = Interstate.objects.length()

   304             if oracle: tol = 2

   305             else: tol = 5

   306             self.assertAlmostEqual(len_m1, qs[0].length.m, tol)

   307 

   308         # Now doing length on a projected coordinate system.

   309         i10 = SouthTexasInterstate.objects.length().get(name='I-10')

   310         self.assertAlmostEqual(len_m2, i10.length.m, 2)

   311 

   312     @no_spatialite

   313     def test08_perimeter(self):

   314         "Testing the `perimeter` GeoQuerySet method."

   315         # Reference query:

   316         # SELECT ST_Perimeter(distapp_southtexaszipcode.poly) FROM distapp_southtexaszipcode;

   317         perim_m = [18404.3550889361, 15627.2108551001, 20632.5588368978, 17094.5996143697]

   318         if oracle: tol = 2

   319         else: tol = 7

   320         for i, z in enumerate(SouthTexasZipcode.objects.perimeter()):

   321             self.assertAlmostEqual(perim_m[i], z.perimeter.m, tol)

   322 

   323         # Running on points; should return 0.

   324         for i, c in enumerate(SouthTexasCity.objects.perimeter(model_att='perim')):

   325             self.assertEqual(0, c.perim.m)

   326 

   327 def suite():

   328     s = unittest.TestSuite()

   329     s.addTest(unittest.makeSuite(DistanceTest))

   330     return s