python/lib/django-1.2/django/contrib/gis/geometry/test_data.py

   1 """
   2 This module has the mock object definitions used to hold reference geometry
   3 for the GEOS and GDAL tests.
   4 """
   5 import gzip
   6 import os
   7
   8 from django.contrib import gis
   9 from django.utils import simplejson
  10
  11
  12 # This global used to store reference geometry data.
  13 GEOMETRIES = None
  14
  15 # Path where reference test data is located.
  16 TEST_DATA = os.path.join(os.path.dirname(gis.__file__), 'tests', 'data')
  17
  18
  19 def tuplize(seq):
  20     "Turn all nested sequences to tuples in given sequence."
  21     if isinstance(seq, (list, tuple)):
  22         return tuple([tuplize(i) for i in seq])
  23     return seq
  24
  25
  26 def strconvert(d):
  27     "Converts all keys in dictionary to str type."
  28     return dict([(str(k), v) for k, v in d.iteritems()])
  29
  30
  31 def get_ds_file(name, ext):
  32     return os.path.join(TEST_DATA,
  33                         name,
  34                         name + '.%s' % ext
  35                         )
  36
  37
  38 class TestObj(object):
  39     """
  40     Base testing object, turns keyword args into attributes.
  41     """
  42     def __init__(self, **kwargs):
  43         for key, value in kwargs.items():
  44             setattr(self, key, value)
  45
  46
  47 class TestDS(TestObj):
  48     """
  49     Object for testing GDAL data sources.
  50     """
  51     def __init__(self, name, **kwargs):
  52         # Shapefile is default extension, unless specified otherwise.
  53         ext = kwargs.pop('ext', 'shp')
  54         self.ds = get_ds_file(name, ext)
  55         super(TestDS, self).__init__(**kwargs)
  56
  57
  58 class TestGeom(TestObj):
  59     """
  60     Testing object used for wrapping reference geometry data
  61     in GEOS/GDAL tests.
  62     """
  63     def __init__(self, **kwargs):
  64         # Converting lists to tuples of certain keyword args
  65         # so coordinate test cases will match (JSON has no
  66         # concept of tuple).
  67         coords = kwargs.pop('coords', None)
  68         if coords:
  69             self.coords = tuplize(coords)
  70
  71         centroid = kwargs.pop('centroid', None)
  72         if centroid:
  73             self.centroid = tuple(centroid)
  74
  75         ext_ring_cs = kwargs.pop('ext_ring_cs', None)
  76         if ext_ring_cs:
  77             ext_ring_cs = tuplize(ext_ring_cs)
  78         self.ext_ring_cs = ext_ring_cs
  79
  80         super(TestGeom, self).__init__(**kwargs)
  81
  82
  83 class TestGeomSet(object):
  84     """
  85     Each attribute of this object is a list of `TestGeom` instances.
  86     """
  87     def __init__(self, **kwargs):
  88         for key, value in kwargs.items():
  89             setattr(self, key, [TestGeom(**strconvert(kw)) for kw in value])
  90
  91
  92 class TestDataMixin(object):
  93     """
  94     Mixin used for GEOS/GDAL test cases that defines a `geometries`
  95     property, which returns and/or loads the reference geometry data.
  96     """
  97     @property
  98     def geometries(self):
  99         global GEOMETRIES
 100         if GEOMETRIES is None:
 101             # Load up the test geometry data from fixture into global.
 102             gzf = gzip.GzipFile(os.path.join(TEST_DATA, 'geometries.json.gz'))
 103             geometries = simplejson.loads(gzf.read())
 104             GEOMETRIES = TestGeomSet(**strconvert(geometries))
 105         return GEOMETRIES