id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
27014	Raster support for spatial lookup breaks filtering by annotations	Tristen Georgiou	nobody	"This maybe a very specific edge case; I noticed that my website unit tests break when I upgraded to 1.10 and it appears to occur when I filter spatially and then annotate and then filter upon that annotation. (using Python 3, and the django.contrib.gis.db.backends.postgis backend)

Here's code to reproduce:
models.py
{{{
from django.contrib.gis.db import models

class Event(models.Model):
    enabled = models.BooleanField(default=True, db_index=True)
    location = models.PointField(geography=True)
    distance = models.IntegerField(default=5)

    objects = models.GeoManager()
}}}

And a unit test to show the error:
tests.py
{{{
from django.contrib.gis.measure import D
from django.db.models import F
from django.test import TestCase
from django.contrib.gis.geos import Point
from django.contrib.gis.db.models.functions import Distance

from polls.models import Event

class SampleTest(TestCase):
    def test_something(self):
        centre = Point(0.0, 0.0)
        query = Event.objects.filter(location__dwithin=(centre, D(km=5)))
        query = query.annotate(
            actual_distance=Distance('location', centre)
        ).filter(
            actual_distance__lte=F('distance') * 1000)
        print(list(query.all()))
}}}

And stacktrace:
{{{
Traceback (most recent call last):
  File ""/Users/tristeng/PycharmProjects/rastertest/polls/tests.py"", line 18, in test_something
    print(list(query.all()))
  File ""/Users/tristeng/venvs/djangotest/lib/python3.4/site-packages/django/db/models/query.py"", line 256, in __iter__
    self._fetch_all()
  File ""/Users/tristeng/venvs/djangotest/lib/python3.4/site-packages/django/db/models/query.py"", line 1085, in _fetch_all
    self._result_cache = list(self.iterator())
  File ""/Users/tristeng/venvs/djangotest/lib/python3.4/site-packages/django/db/models/query.py"", line 54, in __iter__
    results = compiler.execute_sql()
  File ""/Users/tristeng/venvs/djangotest/lib/python3.4/site-packages/django/db/models/sql/compiler.py"", line 824, in execute_sql
    sql, params = self.as_sql()
  File ""/Users/tristeng/venvs/djangotest/lib/python3.4/site-packages/django/db/models/sql/compiler.py"", line 376, in as_sql
    where, w_params = self.compile(self.where) if self.where is not None else ("""", [])
  File ""/Users/tristeng/venvs/djangotest/lib/python3.4/site-packages/django/db/models/sql/compiler.py"", line 353, in compile
    sql, params = node.as_sql(self, self.connection)
  File ""/Users/tristeng/venvs/djangotest/lib/python3.4/site-packages/django/db/models/sql/where.py"", line 79, in as_sql
    sql, params = compiler.compile(child)
  File ""/Users/tristeng/venvs/djangotest/lib/python3.4/site-packages/django/db/models/sql/compiler.py"", line 353, in compile
    sql, params = node.as_sql(self, self.connection)
  File ""/Users/tristeng/venvs/djangotest/lib/python3.4/site-packages/django/db/models/lookups.py"", line 155, in as_sql
    lhs_sql, params = self.process_lhs(compiler, connection)
  File ""/Users/tristeng/venvs/djangotest/lib/python3.4/site-packages/django/db/models/lookups.py"", line 146, in process_lhs
    compiler, connection, lhs)
  File ""/Users/tristeng/venvs/djangotest/lib/python3.4/site-packages/django/db/models/lookups.py"", line 67, in process_lhs
    return compiler.compile(lhs)
  File ""/Users/tristeng/venvs/djangotest/lib/python3.4/site-packages/django/db/models/sql/compiler.py"", line 351, in compile
    sql, params = vendor_impl(self, self.connection)
  File ""/Users/tristeng/venvs/djangotest/lib/python3.4/site-packages/django/contrib/gis/db/models/functions.py"", line 252, in as_postgresql
    return super(Distance, self).as_sql(compiler, connection)
  File ""/Users/tristeng/venvs/djangotest/lib/python3.4/site-packages/django/contrib/gis/db/models/functions.py"", line 43, in as_sql
    return super(GeoFunc, self).as_sql(compiler, connection)
  File ""/Users/tristeng/venvs/djangotest/lib/python3.4/site-packages/django/db/models/expressions.py"", line 521, in as_sql
    arg_sql, arg_params = compiler.compile(arg)
  File ""/Users/tristeng/venvs/djangotest/lib/python3.4/site-packages/django/db/models/sql/compiler.py"", line 351, in compile
    sql, params = vendor_impl(self, self.connection)
  File ""/Users/tristeng/venvs/djangotest/lib/python3.4/site-packages/django/contrib/gis/db/models/functions.py"", line 82, in as_postgresql
    self.value = connection.ops.Adapter(self.value, geography=self.geography)
  File ""/Users/tristeng/venvs/djangotest/lib/python3.4/site-packages/django/contrib/gis/db/backends/postgis/adapter.py"", line 26, in __init__
    self.ewkb = to_pgraster(obj)
  File ""/Users/tristeng/venvs/djangotest/lib/python3.4/site-packages/django/contrib/gis/db/backends/postgis/pgraster.py"", line 123, in to_pgraster
    1, 0, len(rast.bands), rast.scale.x, rast.scale.y,
AttributeError: 'PostGISAdapter' object has no attribute 'bands'
}}}

It looks like PostGISAdapter initializer needs to handle the additional case where the type of 'obj' passed into the constructor is actually of it's own type, otherwise it assumes its a PGRaster and attempts to convert it; do we need to check isinstance(obj, PostGISAdapter) and handle accordingly?
{{{
class PostGISAdapter(object):
    def __init__(self, obj, geography=False):
        """"""
        Initialize on the spatial object.
        """"""
        self.is_geometry = isinstance(obj, Geometry)

        # Getting the WKB (in string form, to allow easy pickling of
        # the adaptor) and the SRID from the geometry or raster.
        if self.is_geometry:
            self.ewkb = bytes(obj.ewkb)
            self._adapter = Binary(self.ewkb)
        else:
            self.ewkb = to_pgraster(obj)

        self.srid = obj.srid
        self.geography = geography
}}}
"	Bug	closed	GIS	1.10	Release blocker	fixed	raster, spatial	Daniel Wiesmann	Ready for checkin	1	0	0	0	0	0