From 72c39410c80ee842bf3de22418086d102cb2b768 Mon Sep 17 00:00:00 2001
From: Justin Bronn <jbronn@gmail.com>
Date: Fri, 29 Jan 2010 02:46:07 +0000
Subject: [PATCH] Renamed `reverse` to `reverse_geom` because of clash with
 existing `QuerySet` method; added `GeoQuerySet.geohash` support for producing
 GeoHash reprsentations.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@12350 bcc190cf-cafb-0310-a4f2-bffc1f526a37
---
 django/contrib/gis/db/models/manager.py  |  7 +++++--
 django/contrib/gis/db/models/query.py    | 17 ++++++++++++++++-
 django/contrib/gis/tests/geoapp/tests.py | 23 +++++++++++++++++++----
 3 files changed, 40 insertions(+), 7 deletions(-)

diff --git a/django/contrib/gis/db/models/manager.py b/django/contrib/gis/db/models/manager.py
index 1e936c79cd..61fb82132b 100644
--- a/django/contrib/gis/db/models/manager.py
+++ b/django/contrib/gis/db/models/manager.py
@@ -39,6 +39,9 @@ class GeoManager(Manager):
     def force_rhr(self, *args, **kwargs):
         return self.get_query_set().force_rhr(*args, **kwargs)
 
+    def geohash(self, *args, **kwargs):
+        return self.get_query_set().geohash(*args, **kwargs)
+
     def geojson(self, *args, **kwargs):
         return self.get_query_set().geojson(*args, **kwargs)
 
@@ -72,8 +75,8 @@ class GeoManager(Manager):
     def point_on_surface(self, *args, **kwargs):
         return self.get_query_set().point_on_surface(*args, **kwargs)
 
-    def reverse(self, *args, **kwargs):
-        return self.get_query_set().reverse(*args, **kwargs)
+    def reverse_geom(self, *args, **kwargs):
+        return self.get_query_set().reverse_geom(*args, **kwargs)
 
     def scale(self, *args, **kwargs):
         return self.get_query_set().scale(*args, **kwargs)
diff --git a/django/contrib/gis/db/models/query.py b/django/contrib/gis/db/models/query.py
index 781df8c76f..79eed853f9 100644
--- a/django/contrib/gis/db/models/query.py
+++ b/django/contrib/gis/db/models/query.py
@@ -162,6 +162,20 @@ class GeoQuerySet(QuerySet):
              }
         return self._spatial_attribute('geojson', s, **kwargs)
 
+    def geohash(self, precision=20, **kwargs):
+        """
+        Returns a GeoHash representation of the given field in a `geohash`
+        attribute on each element of the GeoQuerySet.
+
+        The `precision` keyword may be used to custom the number of
+        _characters_ used in the output GeoHash, the default is 20.
+        """
+        s = {'desc' : 'GeoHash', 
+             'procedure_args': {'precision': precision},
+             'procedure_fmt': '%(geo_col)s,%(precision)s',
+             }
+        return self._spatial_attribute('geohash', s, **kwargs)
+
     def gml(self, precision=8, version=2, **kwargs):
         """
         Returns GML representation of the given field in a `gml` attribute
@@ -253,12 +267,13 @@ class GeoQuerySet(QuerySet):
         """
         return self._geom_attribute('point_on_surface', **kwargs)
 
-    def reverse(self, **kwargs):
+    def reverse_geom(self, **kwargs):
         """
         Reverses the coordinate order of the geometry, and attaches as a
         `reverse` attribute on each element of this GeoQuerySet.
         """
         s = {'select_field' : GeomField(),}
+        kwargs.setdefault('model_att', 'reverse_geom')
         if connections[self.db].ops.oracle:
             s['geo_field_type'] = LineStringField
         return self._spatial_attribute('reverse', s, **kwargs)
diff --git a/django/contrib/gis/tests/geoapp/tests.py b/django/contrib/gis/tests/geoapp/tests.py
index ba662bb48b..ab915896e5 100644
--- a/django/contrib/gis/tests/geoapp/tests.py
+++ b/django/contrib/gis/tests/geoapp/tests.py
@@ -690,14 +690,14 @@ class GeoModelTest(TestCase):
     @no_mysql
     @no_spatialite
     def test28_reverse(self):
-        "Testing GeoQuerySet.reverse()."
+        "Testing GeoQuerySet.reverse_geom()."
         coords = [ (-95.363151, 29.763374), (-95.448601, 29.713803) ]
         Track.objects.create(name='Foo', line=LineString(coords))
-        t = Track.objects.reverse().get(name='Foo')
+        t = Track.objects.reverse_geom().get(name='Foo')
         coords.reverse()
-        self.assertEqual(tuple(coords), t.reverse.coords)
+        self.assertEqual(tuple(coords), t.reverse_geom.coords)
         if oracle:
-            self.assertRaises(TypeError, State.objects.reverse)
+            self.assertRaises(TypeError, State.objects.reverse_geom)
         
     @no_mysql
     @no_oracle
@@ -714,6 +714,21 @@ class GeoModelTest(TestCase):
         s = State.objects.force_rhr().get(name='Foo')
         self.assertEqual(rhr_rings, s.force_rhr.coords)
 
+    @no_mysql
+    @no_oracle
+    @no_spatialite
+    def test29_force_rhr(self):
+        "Testing GeoQuerySet.geohash()."
+        if not connection.ops.geohash: return
+        # Reference query:
+        # SELECT ST_GeoHash(point) FROM geoapp_city WHERE name='Houston';
+        # SELECT ST_GeoHash(point, 5) FROM geoapp_city WHERE name='Houston';
+        ref_hash = '9vk1mfq8jx0c8e0386z6'
+        h1 = City.objects.geohash().get(name='Houston')
+        h2 = City.objects.geohash(precision=5).get(name='Houston')
+        self.assertEqual(ref_hash, h1.geohash)
+        self.assertEqual(ref_hash[:5], h2.geohash)
+
 from test_feeds import GeoFeedTest
 from test_regress import GeoRegressionTests
 from test_sitemaps import GeoSitemapTest