Converted GIS lookups to use the new Lookup API

Thanks Tim Graham, Anssi Kääriäinen and Marc Tamlyn for the
reviews.

11 files changed, 408 insertions, 485 deletions

diff --git a/django/contrib/gis/db/backends/base.py b/django/contrib/gis/db/backends/base.py
index a132e80661..c6e48ce0ef 100644
--- a/django/contrib/gis/db/backends/base.py
+++ b/django/contrib/gis/db/backends/base.py
@@ -42,19 +42,19 @@ class BaseSpatialFeatures(object):
 
     @property
     def supports_bbcontains_lookup(self):
-        return 'bbcontains' in self.connection.ops.gis_terms
+        return 'bbcontains' in self.connection.ops.gis_operators
 
     @property
     def supports_contained_lookup(self):
-        return 'contained' in self.connection.ops.gis_terms
+        return 'contained' in self.connection.ops.gis_operators
 
     @property
     def supports_dwithin_lookup(self):
-        return 'dwithin' in self.connection.ops.distance_functions
+        return 'dwithin' in self.connection.ops.gis_operators
 
     @property
     def supports_relate_lookup(self):
-        return 'relate' in self.connection.ops.gis_terms
+        return 'relate' in self.connection.ops.gis_operators
 
     # For each of those methods, the class will have a property named
     # `has_<name>_method` (defined in __init__) which accesses connection.ops
@@ -97,12 +97,6 @@ class BaseSpatialOperations(object):
     instantiated by each spatial database backend with the features
     it has.
     """
-    distance_functions = {}
-    geometry_functions = {}
-    geometry_operators = {}
-    geography_operators = {}
-    geography_functions = {}
-    gis_terms = set()
     truncate_params = {}
 
     # Quick booleans for the type of this spatial backend, and
@@ -215,9 +209,6 @@ class BaseSpatialOperations(object):
     def spatial_aggregate_sql(self, agg):
         raise NotImplementedError('Aggregate support not implemented for this spatial backend.')
 
-    def spatial_lookup_sql(self, lvalue, lookup_type, value, field):
-        raise NotImplementedError('subclasses of BaseSpatialOperations must a provide spatial_lookup_sql() method')
-
     # Routines for getting the OGC-compliant models.
     def geometry_columns(self):
         raise NotImplementedError('subclasses of BaseSpatialOperations must a provide geometry_columns() method')
diff --git a/django/contrib/gis/db/backends/mysql/operations.py b/django/contrib/gis/db/backends/mysql/operations.py
index a9e264cb02..bcbd634fd8 100644
--- a/django/contrib/gis/db/backends/mysql/operations.py
+++ b/django/contrib/gis/db/backends/mysql/operations.py
@@ -2,6 +2,7 @@ from django.db.backends.mysql.base import DatabaseOperations
 
 from django.contrib.gis.db.backends.adapter import WKTAdapter
 from django.contrib.gis.db.backends.base import BaseSpatialOperations
+from django.contrib.gis.db.backends.utils import SpatialOperator
 
 
 class MySQLOperations(DatabaseOperations, BaseSpatialOperations):
@@ -16,27 +17,25 @@ class MySQLOperations(DatabaseOperations, BaseSpatialOperations):
     Adapter = WKTAdapter
     Adaptor = Adapter  # Backwards-compatibility alias.
 
-    geometry_functions = {
-        'bbcontains': 'MBRContains',  # For consistency w/PostGIS API
-        'bboverlaps': 'MBROverlaps',  # .. ..
-        'contained': 'MBRWithin',    # .. ..
-        'contains': 'MBRContains',
-        'disjoint': 'MBRDisjoint',
-        'equals': 'MBREqual',
-        'exact': 'MBREqual',
-        'intersects': 'MBRIntersects',
-        'overlaps': 'MBROverlaps',
-        'same_as': 'MBREqual',
-        'touches': 'MBRTouches',
-        'within': 'MBRWithin',
+    gis_operators = {
+        'bbcontains': SpatialOperator(func='MBRContains'),  # For consistency w/PostGIS API
+        'bboverlaps': SpatialOperator(func='MBROverlaps'),  # .. ..
+        'contained': SpatialOperator(func='MBRWithin'),    # .. ..
+        'contains': SpatialOperator(func='MBRContains'),
+        'disjoint': SpatialOperator(func='MBRDisjoint'),
+        'equals': SpatialOperator(func='MBREqual'),
+        'exact': SpatialOperator(func='MBREqual'),
+        'intersects': SpatialOperator(func='MBRIntersects'),
+        'overlaps': SpatialOperator(func='MBROverlaps'),
+        'same_as': SpatialOperator(func='MBREqual'),
+        'touches': SpatialOperator(func='MBRTouches'),
+        'within': SpatialOperator(func='MBRWithin'),
     }
 
-    gis_terms = set(geometry_functions) | {'isnull'}
-
     def geo_db_type(self, f):
         return f.geom_type
 
-    def get_geom_placeholder(self, value, srid):
+    def get_geom_placeholder(self, f, value):
         """
         The placeholder here has to include MySQL's WKT constructor.  Because
         MySQL does not support spatial transformations, there is no need to
@@ -47,19 +46,3 @@ class MySQLOperations(DatabaseOperations, BaseSpatialOperations):
         else:
             placeholder = '%s(%%s)' % self.from_text
         return placeholder
-
-    def spatial_lookup_sql(self, lvalue, lookup_type, value, field, qn):
-        geo_col, db_type = lvalue
-
-        lookup_info = self.geometry_functions.get(lookup_type, False)
-        if lookup_info:
-            sql = "%s(%s, %s)" % (lookup_info, geo_col,
-                                  self.get_geom_placeholder(value, field.srid))
-            return sql, []
-
-        # TODO: Is this really necessary? MySQL can't handle NULL geometries
-        #  in its spatial indexes anyways.
-        if lookup_type == 'isnull':
-            return "%s IS %sNULL" % (geo_col, ('' if value else 'NOT ')), []
-
-        raise TypeError("Got invalid lookup_type: %s" % repr(lookup_type))
diff --git a/django/contrib/gis/db/backends/oracle/operations.py b/django/contrib/gis/db/backends/oracle/operations.py
index 45ebdf32d3..a305f81f58 100644
--- a/django/contrib/gis/db/backends/oracle/operations.py
+++ b/django/contrib/gis/db/backends/oracle/operations.py
@@ -244,6 +244,12 @@ class OracleOperations(DatabaseOperations, BaseSpatialOperations):
             else:
                 return 'SDO_GEOMETRY(%%s, %s)' % f.srid
 
+    def check_relate_argument(self, arg):
+        masks = 'TOUCH|OVERLAPBDYDISJOINT|OVERLAPBDYINTERSECT|EQUAL|INSIDE|COVEREDBY|CONTAINS|COVERS|ANYINTERACT|ON'
+        mask_regex = re.compile(r'^(%s)(\+(%s))*$' % (masks, masks), re.I)
+        if not self.mask_regex.match(arg):
+            raise ValueError('Invalid SDO_RELATE mask: "%s"' % (self.relate_func, arg))
+
     def spatial_lookup_sql(self, lvalue, lookup_type, value, field, qn):
         "Returns the SQL WHERE clause for use in Oracle spatial SQL construction."
         geo_col, db_type = lvalue
diff --git a/django/contrib/gis/db/backends/postgis/operations.py b/django/contrib/gis/db/backends/postgis/operations.py
index c41748cca2..690194fa9e 100644
--- a/django/contrib/gis/db/backends/postgis/operations.py
+++ b/django/contrib/gis/db/backends/postgis/operations.py
@@ -1,73 +1,46 @@
 import re
-from decimal import Decimal
 
 from django.conf import settings
 from django.contrib.gis.db.backends.base import BaseSpatialOperations
-from django.contrib.gis.db.backends.utils import SpatialOperation, SpatialFunction
 from django.contrib.gis.db.backends.postgis.adapter import PostGISAdapter
+from django.contrib.gis.db.backends.utils import SpatialOperator
 from django.contrib.gis.geometry.backend import Geometry
 from django.contrib.gis.measure import Distance
 from django.core.exceptions import ImproperlyConfigured
 from django.db.backends.postgresql_psycopg2.base import DatabaseOperations
 from django.db.utils import ProgrammingError
-from django.utils import six
 from django.utils.functional import cached_property
 
 from .models import PostGISGeometryColumns, PostGISSpatialRefSys
 
 
-#### Classes used in constructing PostGIS spatial SQL ####
-class PostGISOperator(SpatialOperation):
-    "For PostGIS operators (e.g. `&&`, `~`)."
-    def __init__(self, operator):
-        super(PostGISOperator, self).__init__(operator=operator)
-
-
-class PostGISFunction(SpatialFunction):
-    "For PostGIS function calls (e.g., `ST_Contains(table, geom)`)."
-    def __init__(self, prefix, function, **kwargs):
-        super(PostGISFunction, self).__init__(prefix + function, **kwargs)
-
-
-class PostGISFunctionParam(PostGISFunction):
-    "For PostGIS functions that take another parameter (e.g. DWithin, Relate)."
-    sql_template = '%(function)s(%(geo_col)s, %(geometry)s, %%s)'
-
-
-class PostGISDistance(PostGISFunction):
-    "For PostGIS distance operations."
-    dist_func = 'Distance'
-    sql_template = '%(function)s(%(geo_col)s, %(geometry)s) %(operator)s %%s'
-
-    def __init__(self, prefix, operator):
-        super(PostGISDistance, self).__init__(prefix, self.dist_func,
-                                              operator=operator)
-
-
-class PostGISSpheroidDistance(PostGISFunction):
-    "For PostGIS spherical distance operations (using the spheroid)."
-    dist_func = 'distance_spheroid'
-    sql_template = '%(function)s(%(geo_col)s, %(geometry)s, %%s) %(operator)s %%s'
-
-    def __init__(self, prefix, operator):
-        # An extra parameter in `end_subst` is needed for the spheroid string.
-        super(PostGISSpheroidDistance, self).__init__(prefix, self.dist_func,
-                                                      operator=operator)
-
+class PostGISOperator(SpatialOperator):
+    def __init__(self, geography=False, **kwargs):
+        # Only a subset of the operators and functions are available
+        # for the geography type.
+        self.geography = geography
+        super(PostGISOperator, self).__init__(**kwargs)
 
-class PostGISSphereDistance(PostGISDistance):
-    "For PostGIS spherical distance operations."
-    dist_func = 'distance_sphere'
+    def as_sql(self, connection, lookup, *args):
+        if lookup.lhs.source.geography and not self.geography:
+            raise ValueError('PostGIS geography does not support the "%s" '
+                             'function/operator.' % (self.func or self.op,))
+        return super(PostGISOperator, self).as_sql(connection, lookup, *args)
 
 
-class PostGISRelate(PostGISFunctionParam):
-    "For PostGIS Relate(<geom>, <pattern>) calls."
-    pattern_regex = re.compile(r'^[012TF\*]{9}$')
+class PostGISDistanceOperator(PostGISOperator):
+    sql_template = '%(func)s(%(lhs)s, %(rhs)s) %(op)s %%s'
 
-    def __init__(self, prefix, pattern):
-        if not self.pattern_regex.match(pattern):
-            raise ValueError('Invalid intersection matrix pattern "%s".' % pattern)
-        super(PostGISRelate, self).__init__(prefix, 'Relate')
+    def as_sql(self, connection, lookup, template_params, sql_params):
+        if not lookup.lhs.source.geography and lookup.lhs.source.geodetic(connection):
+            sql_template = self.sql_template
+            if len(lookup.rhs) == 3 and lookup.rhs[-1] == 'spheroid':
+                template_params.update({'op': self.op, 'func': 'ST_Distance_Spheroid'})
+                sql_template = '%(func)s(%(lhs)s, %(rhs)s, %%s) %(op)s %%s'
+            else:
+                template_params.update({'op': self.op, 'func': 'ST_Distance_Sphere'})
+            return sql_template % template_params, sql_params
+        return super(PostGISDistanceOperator, self).as_sql(connection, lookup, template_params, sql_params)
 
 
 class PostGISOperations(DatabaseOperations, BaseSpatialOperations):
@@ -82,104 +55,43 @@ class PostGISOperations(DatabaseOperations, BaseSpatialOperations):
     Adapter = PostGISAdapter
     Adaptor = Adapter  # Backwards-compatibility alias.
 
+    gis_operators = {
+        'bbcontains': PostGISOperator(op='~'),
+        'bboverlaps': PostGISOperator(op='&&', geography=True),
+        'contained': PostGISOperator(op='@'),
+        'contains': PostGISOperator(func='ST_Contains'),
+        'overlaps_left': PostGISOperator(op='&<'),
+        'overlaps_right': PostGISOperator(op='&>'),
+        'overlaps_below': PostGISOperator(op='&<|'),
+        'overlaps_above': PostGISOperator(op='|&>'),
+        'left': PostGISOperator(op='<<'),
+        'right': PostGISOperator(op='>>'),
+        'strictly_below': PostGISOperator(op='<<|'),
+        'stricly_above': PostGISOperator(op='|>>'),
+        'same_as': PostGISOperator(op='~='),
+        'exact': PostGISOperator(op='~='),  # alias of same_as
+        'contains_properly': PostGISOperator(func='ST_ContainsProperly'),
+        'coveredby': PostGISOperator(func='ST_CoveredBy', geography=True),
+        'covers': PostGISOperator(func='ST_Covers', geography=True),
+        'crosses': PostGISOperator(func='ST_Crosses)'),
+        'disjoint': PostGISOperator(func='ST_Disjoint'),
+        'equals': PostGISOperator(func='ST_Equals'),
+        'intersects': PostGISOperator(func='ST_Intersects', geography=True),
+        'overlaps': PostGISOperator(func='ST_Overlaps'),
+        'relate': PostGISOperator(func='ST_Relate'),
+        'touches': PostGISOperator(func='ST_Touches'),
+        'within': PostGISOperator(func='ST_Within'),
+        'dwithin': PostGISOperator(func='ST_DWithin', geography=True),
+        'distance_gt': PostGISDistanceOperator(func='ST_Distance', op='>', geography=True),
+        'distance_gte': PostGISDistanceOperator(func='ST_Distance', op='>=', geography=True),
+        'distance_lt': PostGISDistanceOperator(func='ST_Distance', op='<', geography=True),
+        'distance_lte': PostGISDistanceOperator(func='ST_Distance', op='<=', geography=True),
+    }
+
     def __init__(self, connection):
         super(PostGISOperations, self).__init__(connection)
 
         prefix = self.geom_func_prefix
-        # PostGIS-specific operators. The commented descriptions of these
-        # operators come from Section 7.6 of the PostGIS 1.4 documentation.
-        self.geometry_operators = {
-            # The "&<" operator returns true if A's bounding box overlaps or
-            # is to the left of B's bounding box.
-            'overlaps_left': PostGISOperator('&<'),
-            # The "&>" operator returns true if A's bounding box overlaps or
-            # is to the right of B's bounding box.
-            'overlaps_right': PostGISOperator('&>'),
-            # The "<<" operator returns true if A's bounding box is strictly
-            # to the left of B's bounding box.
-            'left': PostGISOperator('<<'),
-            # The ">>" operator returns true if A's bounding box is strictly
-            # to the right of B's bounding box.
-            'right': PostGISOperator('>>'),
-            # The "&<|" operator returns true if A's bounding box overlaps or
-            # is below B's bounding box.
-            'overlaps_below': PostGISOperator('&<|'),
-            # The "|&>" operator returns true if A's bounding box overlaps or
-            # is above B's bounding box.
-            'overlaps_above': PostGISOperator('|&>'),
-            # The "<<|" operator returns true if A's bounding box is strictly
-            # below B's bounding box.
-            'strictly_below': PostGISOperator('<<|'),
-            # The "|>>" operator returns true if A's bounding box is strictly
-            # above B's bounding box.
-            'strictly_above': PostGISOperator('|>>'),
-            # The "~=" operator is the "same as" operator. It tests actual
-            # geometric equality of two features. So if A and B are the same feature,
-            # vertex-by-vertex, the operator returns true.
-            'same_as': PostGISOperator('~='),
-            'exact': PostGISOperator('~='),
-            # The "@" operator returns true if A's bounding box is completely contained
-            # by B's bounding box.
-            'contained': PostGISOperator('@'),
-            # The "~" operator returns true if A's bounding box completely contains
-            #  by B's bounding box.
-            'bbcontains': PostGISOperator('~'),
-            # The "&&" operator returns true if A's bounding box overlaps
-            # B's bounding box.
-            'bboverlaps': PostGISOperator('&&'),
-        }
-
-        self.geometry_functions = {
-            'equals': PostGISFunction(prefix, 'Equals'),
-            'disjoint': PostGISFunction(prefix, 'Disjoint'),
-            'touches': PostGISFunction(prefix, 'Touches'),
-            'crosses': PostGISFunction(prefix, 'Crosses'),
-            'within': PostGISFunction(prefix, 'Within'),
-            'overlaps': PostGISFunction(prefix, 'Overlaps'),
-            'contains': PostGISFunction(prefix, 'Contains'),
-            'intersects': PostGISFunction(prefix, 'Intersects'),
-            'relate': (PostGISRelate, six.string_types),
-            'coveredby': PostGISFunction(prefix, 'CoveredBy'),
-            'covers': PostGISFunction(prefix, 'Covers'),
-            'contains_properly': PostGISFunction(prefix, 'ContainsProperly'),
-        }
-
-        # Valid distance types and substitutions
-        dtypes = (Decimal, Distance, float) + six.integer_types
-
-        def get_dist_ops(operator):
-            "Returns operations for both regular and spherical distances."
-            return {'cartesian': PostGISDistance(prefix, operator),
-                    'sphere': PostGISSphereDistance(prefix, operator),
-                    'spheroid': PostGISSpheroidDistance(prefix, operator),
-                    }
-        self.distance_functions = {
-            'distance_gt': (get_dist_ops('>'), dtypes),
-            'distance_gte': (get_dist_ops('>='), dtypes),
-            'distance_lt': (get_dist_ops('<'), dtypes),
-            'distance_lte': (get_dist_ops('<='), dtypes),
-            'dwithin': (PostGISFunctionParam(prefix, 'DWithin'), dtypes)
-        }
-
-        # Adding the distance functions to the geometries lookup.
-        self.geometry_functions.update(self.distance_functions)
-
-        # Only a subset of the operators and functions are available
-        # for the geography type.
-        self.geography_functions = self.distance_functions.copy()
-        self.geography_functions.update({
-            'coveredby': self.geometry_functions['coveredby'],
-            'covers': self.geometry_functions['covers'],
-            'intersects': self.geometry_functions['intersects'],
-        })
-        self.geography_operators = {
-            'bboverlaps': PostGISOperator('&&'),
-        }
-
-        # Creating a dictionary lookup of all GIS terms for PostGIS.
-        self.gis_terms = {'isnull'}
-        self.gis_terms.update(self.geometry_operators)
-        self.gis_terms.update(self.geometry_functions)
 
         self.area = prefix + 'Area'
         self.bounding_circle = prefix + 'MinimumBoundingCircle'
@@ -452,95 +364,6 @@ class PostGISOperations(DatabaseOperations, BaseSpatialOperations):
         else:
             raise Exception('Could not determine PROJ.4 version from PostGIS.')
 
-    def num_params(self, lookup_type, num_param):
-        """
-        Helper routine that returns a boolean indicating whether the number of
-        parameters is correct for the lookup type.
-        """
-        def exactly_two(np):
-            return np == 2
-
-        def two_to_three(np):
-            return np >= 2 and np <= 3
-        if (lookup_type in self.distance_functions and
-                lookup_type != 'dwithin'):
-            return two_to_three(num_param)
-        else:
-            return exactly_two(num_param)
-
-    def spatial_lookup_sql(self, lvalue, lookup_type, value, field, qn):
-        """
-        Constructs spatial SQL from the given lookup value tuple a
-        (alias, col, db_type), the lookup type string, lookup value, and
-        the geometry field.
-        """
-        geo_col, db_type = lvalue
-
-        if lookup_type in self.geometry_operators:
-            if field.geography and lookup_type not in self.geography_operators:
-                raise ValueError('PostGIS geography does not support the '
-                                 '"%s" lookup.' % lookup_type)
-            # Handling a PostGIS operator.
-            op = self.geometry_operators[lookup_type]
-            return op.as_sql(geo_col, self.get_geom_placeholder(field, value))
-        elif lookup_type in self.geometry_functions:
-            if field.geography and lookup_type not in self.geography_functions:
-                raise ValueError('PostGIS geography type does not support the '
-                                 '"%s" lookup.' % lookup_type)
-
-            # See if a PostGIS geometry function matches the lookup type.
-            tmp = self.geometry_functions[lookup_type]
-
-            # Lookup types that are tuples take tuple arguments, e.g., 'relate' and
-            # distance lookups.
-            if isinstance(tmp, tuple):
-                # First element of tuple is the PostGISOperation instance, and the
-                # second element is either the type or a tuple of acceptable types
-                # that may passed in as further parameters for the lookup type.
-                op, arg_type = tmp
-
-                # Ensuring that a tuple _value_ was passed in from the user
-                if not isinstance(value, (tuple, list)):
-                    raise ValueError('Tuple required for `%s` lookup type.' % lookup_type)
-
-                # Geometry is first element of lookup tuple.
-                geom = value[0]
-
-                # Number of valid tuple parameters depends on the lookup type.
-                nparams = len(value)
-                if not self.num_params(lookup_type, nparams):
-                    raise ValueError('Incorrect number of parameters given for `%s` lookup type.' % lookup_type)
-
-                # Ensuring the argument type matches what we expect.
-                if not isinstance(value[1], arg_type):
-                    raise ValueError('Argument type should be %s, got %s instead.' % (arg_type, type(value[1])))
-
-                # For lookup type `relate`, the op instance is not yet created (has
-                # to be instantiated here to check the pattern parameter).
-                if lookup_type == 'relate':
-                    op = op(self.geom_func_prefix, value[1])
-                elif lookup_type in self.distance_functions and lookup_type != 'dwithin':
-                    if not field.geography and field.geodetic(self.connection):
-                        # Setting up the geodetic operation appropriately.
-                        if nparams == 3 and value[2] == 'spheroid':
-                            op = op['spheroid']
-                        else:
-                            op = op['sphere']
-                    else:
-                        op = op['cartesian']
-            else:
-                op = tmp
-                geom = value
-
-            # Calling the `as_sql` function on the operation instance.
-            return op.as_sql(geo_col, self.get_geom_placeholder(field, geom))
-
-        elif lookup_type == 'isnull':
-            # Handling 'isnull' lookup type
-            return "%s IS %sNULL" % (geo_col, ('' if value else 'NOT ')), []
-
-        raise TypeError("Got invalid lookup_type: %s" % repr(lookup_type))
-
     def spatial_aggregate_sql(self, agg):
         """
         Returns the spatial aggregate SQL template and function for the
diff --git a/django/contrib/gis/db/backends/spatialite/operations.py b/django/contrib/gis/db/backends/spatialite/operations.py
index b051b250a4..d95b2f6a13 100644
--- a/django/contrib/gis/db/backends/spatialite/operations.py
+++ b/django/contrib/gis/db/backends/spatialite/operations.py
@@ -1,9 +1,8 @@
 import re
 import sys
-from decimal import Decimal
 
 from django.contrib.gis.db.backends.base import BaseSpatialOperations
-from django.contrib.gis.db.backends.utils import SpatialOperation, SpatialFunction
+from django.contrib.gis.db.backends.utils import SpatialOperator
 from django.contrib.gis.db.backends.spatialite.adapter import SpatiaLiteAdapter
 from django.contrib.gis.geometry.backend import Geometry
 from django.contrib.gis.measure import Distance
@@ -14,52 +13,6 @@ from django.utils import six
 from django.utils.functional import cached_property
 
 
-class SpatiaLiteOperator(SpatialOperation):
-    "For SpatiaLite operators (e.g. `&&`, `~`)."
-    def __init__(self, operator):
-        super(SpatiaLiteOperator, self).__init__(operator=operator)
-
-
-class SpatiaLiteFunction(SpatialFunction):
-    "For SpatiaLite function calls."
-    def __init__(self, function, **kwargs):
-        super(SpatiaLiteFunction, self).__init__(function, **kwargs)
-
-
-class SpatiaLiteFunctionParam(SpatiaLiteFunction):
-    "For SpatiaLite functions that take another parameter."
-    sql_template = '%(function)s(%(geo_col)s, %(geometry)s, %%s)'
-
-
-class SpatiaLiteDistance(SpatiaLiteFunction):
-    "For SpatiaLite distance operations."
-    dist_func = 'Distance'
-    sql_template = '%(function)s(%(geo_col)s, %(geometry)s) %(operator)s %%s'
-
-    def __init__(self, operator):
-        super(SpatiaLiteDistance, self).__init__(self.dist_func,
-                                                 operator=operator)
-
-
-class SpatiaLiteRelate(SpatiaLiteFunctionParam):
-    "For SpatiaLite Relate(<geom>, <pattern>) calls."
-    pattern_regex = re.compile(r'^[012TF\*]{9}$')
-
-    def __init__(self, pattern):
-        if not self.pattern_regex.match(pattern):
-            raise ValueError('Invalid intersection matrix pattern "%s".' % pattern)
-        super(SpatiaLiteRelate, self).__init__('Relate')
-
-
-# Valid distance types and substitutions
-dtypes = (Decimal, Distance, float) + six.integer_types
-
-
-def get_dist_ops(operator):
-    "Returns operations for regular distances; spherical distances are not currently supported."
-    return (SpatiaLiteDistance(operator),)
-
-
 class SpatiaLiteOperations(DatabaseOperations, BaseSpatialOperations):
     compiler_module = 'django.contrib.gis.db.models.sql.compiler'
     name = 'spatialite'
@@ -101,41 +54,31 @@ class SpatiaLiteOperations(DatabaseOperations, BaseSpatialOperations):
     from_wkb = 'GeomFromWKB'
     select = 'AsText(%s)'
 
-    geometry_functions = {
-        'equals': SpatiaLiteFunction('Equals'),
-        'disjoint': SpatiaLiteFunction('Disjoint'),
-        'touches': SpatiaLiteFunction('Touches'),
-        'crosses': SpatiaLiteFunction('Crosses'),
-        'within': SpatiaLiteFunction('Within'),
-        'overlaps': SpatiaLiteFunction('Overlaps'),
-        'contains': SpatiaLiteFunction('Contains'),
-        'intersects': SpatiaLiteFunction('Intersects'),
-        'relate': (SpatiaLiteRelate, six.string_types),
+    gis_operators = {
+        'equals': SpatialOperator(func='Equals'),
+        'disjoint': SpatialOperator(func='Disjoint'),
+        'touches': SpatialOperator(func='Touches'),
+        'crosses': SpatialOperator(func='Crosses'),
+        'within': SpatialOperator(func='Within'),
+        'overlaps': SpatialOperator(func='Overlaps'),
+        'contains': SpatialOperator(func='Contains'),
+        'intersects': SpatialOperator(func='Intersects'),
+        'relate': SpatialOperator(func='Relate'),
         # Returns true if B's bounding box completely contains A's bounding box.
-        'contained': SpatiaLiteFunction('MbrWithin'),
+        'contained': SpatialOperator(func='MbrWithin'),
         # Returns true if A's bounding box completely contains B's bounding box.
-        'bbcontains': SpatiaLiteFunction('MbrContains'),
+        'bbcontains': SpatialOperator(func='MbrContains'),
         # Returns true if A's bounding box overlaps B's bounding box.
-        'bboverlaps': SpatiaLiteFunction('MbrOverlaps'),
+        'bboverlaps': SpatialOperator(func='MbrOverlaps'),
         # These are implemented here as synonyms for Equals
-        'same_as': SpatiaLiteFunction('Equals'),
-        'exact': SpatiaLiteFunction('Equals'),
-    }
+        'same_as': SpatialOperator(func='Equals'),
+        'exact': SpatialOperator(func='Equals'),
 
-    distance_functions = {
-        'distance_gt': (get_dist_ops('>'), dtypes),
-        'distance_gte': (get_dist_ops('>='), dtypes),
-        'distance_lt': (get_dist_ops('<'), dtypes),
-        'distance_lte': (get_dist_ops('<='), dtypes),
+        'distance_gt': SpatialOperator(func='Distance', op='>'),
+        'distance_gte': SpatialOperator(func='Distance', op='>='),
+        'distance_lt': SpatialOperator(func='Distance', op='<'),
+        'distance_lte': SpatialOperator(func='Distance', op='<='),
     }
-    geometry_functions.update(distance_functions)
-
-    def __init__(self, connection):
-        super(DatabaseOperations, self).__init__(connection)
-
-        # Creating the GIS terms dictionary.
-        self.gis_terms = {'isnull'}
-        self.gis_terms.update(self.geometry_functions)
 
     @cached_property
     def spatial_version(self):
@@ -316,58 +259,6 @@ class SpatiaLiteOperations(DatabaseOperations, BaseSpatialOperations):
         sql_function = getattr(self, agg_name)
         return sql_template, sql_function
 
-    def spatial_lookup_sql(self, lvalue, lookup_type, value, field, qn):
-        """
-        Returns the SpatiaLite-specific SQL for the given lookup value
-        [a tuple of (alias, column, db_type)], lookup type, lookup
-        value, the model field, and the quoting function.
-        """
-        geo_col, db_type = lvalue
-
-        if lookup_type in self.geometry_functions:
-            # See if a SpatiaLite geometry function matches the lookup type.
-            tmp = self.geometry_functions[lookup_type]
-
-            # Lookup types that are tuples take tuple arguments, e.g., 'relate' and
-            # distance lookups.
-            if isinstance(tmp, tuple):
-                # First element of tuple is the SpatiaLiteOperation instance, and the
-                # second element is either the type or a tuple of acceptable types
-                # that may passed in as further parameters for the lookup type.
-                op, arg_type = tmp
-
-                # Ensuring that a tuple _value_ was passed in from the user
-                if not isinstance(value, (tuple, list)):
-                    raise ValueError('Tuple required for `%s` lookup type.' % lookup_type)
-
-                # Geometry is first element of lookup tuple.
-                geom = value[0]
-
-                # Number of valid tuple parameters depends on the lookup type.
-                if len(value) != 2:
-                    raise ValueError('Incorrect number of parameters given for `%s` lookup type.' % lookup_type)
-
-                # Ensuring the argument type matches what we expect.
-                if not isinstance(value[1], arg_type):
-                    raise ValueError('Argument type should be %s, got %s instead.' % (arg_type, type(value[1])))
-
-                # For lookup type `relate`, the op instance is not yet created (has
-                # to be instantiated here to check the pattern parameter).
-                if lookup_type == 'relate':
-                    op = op(value[1])
-                elif lookup_type in self.distance_functions:
-                    op = op[0]
-            else:
-                op = tmp
-                geom = value
-            # Calling the `as_sql` function on the operation instance.
-            return op.as_sql(geo_col, self.get_geom_placeholder(field, geom))
-        elif lookup_type == 'isnull':
-            # Handling 'isnull' lookup type
-            return "%s IS %sNULL" % (geo_col, ('' if value else 'NOT ')), []
-
-        raise TypeError("Got invalid lookup_type: %s" % repr(lookup_type))
-
     # Routines for getting the OGC-compliant models.
     def geometry_columns(self):
         from django.contrib.gis.db.backends.spatialite.models import SpatialiteGeometryColumns
diff --git a/django/contrib/gis/db/backends/utils.py b/django/contrib/gis/db/backends/utils.py
index b8b5b9525f..9c3b700852 100644
--- a/django/contrib/gis/db/backends/utils.py
+++ b/django/contrib/gis/db/backends/utils.py
@@ -4,43 +4,24 @@ backends.
 """
 
 
-class SpatialOperation(object):
+class SpatialOperator(object):
     """
-    Base class for generating spatial SQL.
+    Class encapsulating the behavior specific to a GIS operation (used by lookups).
     """
-    sql_template = '%(geo_col)s %(operator)s %(geometry)s'
+    sql_template = None
 
-    def __init__(self, function='', operator='', result='', **kwargs):
-        self.function = function
-        self.operator = operator
-        self.result = result
-        self.extra = kwargs
+    def __init__(self, op=None, func=None):
+        self.op = op
+        self.func = func
 
-    def as_sql(self, geo_col, geometry='%s'):
-        return self.sql_template % self.params(geo_col, geometry), []
+    @property
+    def default_template(self):
+        if self.func:
+            return '%(func)s(%(lhs)s, %(rhs)s)'
+        else:
+            return '%(lhs)s %(op)s %(rhs)s'
 
-    def params(self, geo_col, geometry):
-        params = {'function': self.function,
-                  'geo_col': geo_col,
-                  'geometry': geometry,
-                  'operator': self.operator,
-                  'result': self.result,
-                  }
-        params.update(self.extra)
-        return params
-
-
-class SpatialFunction(SpatialOperation):
-    """
-    Base class for generating spatial SQL related to a function.
-    """
-    sql_template = '%(function)s(%(geo_col)s, %(geometry)s)'
-
-    def __init__(self, func, result='', operator='', **kwargs):
-        # Getting the function prefix.
-        default = {'function': func,
-                   'operator': operator,
-                   'result': result
-                   }
-        kwargs.update(default)
-        super(SpatialFunction, self).__init__(**kwargs)
+    def as_sql(self, connection, lookup, template_params, sql_params):
+        sql_template = self.sql_template or lookup.sql_template or self.default_template
+        template_params.update({'op': self.op, 'func': self.func})
+        return sql_template % template_params, sql_params
diff --git a/django/contrib/gis/db/models/constants.py b/django/contrib/gis/db/models/constants.py
deleted file mode 100644
index 4ece41415c..0000000000
--- a/django/contrib/gis/db/models/constants.py
+++ /dev/null
@@ -1,15 +0,0 @@
-from django.db.models.sql.constants import QUERY_TERMS
-
-GIS_LOOKUPS = {
-    'bbcontains', 'bboverlaps', 'contained', 'contains',
-    'contains_properly', 'coveredby', 'covers', 'crosses', 'disjoint',
-    'distance_gt', 'distance_gte', 'distance_lt', 'distance_lte',
-    'dwithin', 'equals', 'exact',
-    'intersects', 'overlaps', 'relate', 'same_as', 'touches', 'within',
-    'left', 'right', 'overlaps_left', 'overlaps_right',
-    'overlaps_above', 'overlaps_below',
-    'strictly_above', 'strictly_below'
-}
-ALL_TERMS = GIS_LOOKUPS | QUERY_TERMS
-
-__all__ = ['ALL_TERMS', 'GIS_LOOKUPS']
diff --git a/django/contrib/gis/db/models/fields.py b/django/contrib/gis/db/models/fields.py
index c79548ed8a..e260f67cbf 100644
--- a/django/contrib/gis/db/models/fields.py
+++ b/django/contrib/gis/db/models/fields.py
@@ -2,8 +2,7 @@ from django.db.models.fields import Field
 from django.db.models.sql.expressions import SQLEvaluator
 from django.utils.translation import ugettext_lazy as _
 from django.contrib.gis import forms
-from django.contrib.gis.db.models.constants import GIS_LOOKUPS
-from django.contrib.gis.db.models.lookups import GISLookup
+from django.contrib.gis.db.models.lookups import gis_lookups
 from django.contrib.gis.db.models.proxy import GeometryProxy
 from django.contrib.gis.geometry.backend import Geometry, GeometryException
 from django.utils import six
@@ -243,16 +242,15 @@ class GeometryField(Field):
         parameters into the correct units for the coordinate system of the
         field.
         """
-        if lookup_type in connection.ops.gis_terms:
-            # special case for isnull lookup
-            if lookup_type == 'isnull':
-                return []
-
+        # special case for isnull lookup
+        if lookup_type == 'isnull':
+            return []
+        elif lookup_type in self.class_lookups:
             # Populating the parameters list, and wrapping the Geometry
             # with the Adapter of the spatial backend.
             if isinstance(value, (tuple, list)):
                 params = [connection.ops.Adapter(value[0])]
-                if lookup_type in connection.ops.distance_functions:
+                if self.class_lookups[lookup_type].distance:
                     # Getting the distance parameter in the units of the field.
                     params += self.get_distance(value[1:], lookup_type, connection)
                 elif lookup_type in connection.ops.truncate_params:
@@ -291,9 +289,9 @@ class GeometryField(Field):
         """
         return connection.ops.get_geom_placeholder(self, value)
 
-for lookup_name in GIS_LOOKUPS:
-    lookup = type(lookup_name, (GISLookup,), {'lookup_name': lookup_name})
-    GeometryField.register_lookup(lookup)
+
+for klass in gis_lookups.values():
+    GeometryField.register_lookup(klass)
 
 
 # The OpenGIS Geometry Type Fields
diff --git a/django/contrib/gis/db/models/lookups.py b/django/contrib/gis/db/models/lookups.py
index 9552881c6c..d3b53b32f0 100644
--- a/django/contrib/gis/db/models/lookups.py
+++ b/django/contrib/gis/db/models/lookups.py
@@ -1,10 +1,20 @@
+from __future__ import unicode_literals
+import re
+
 from django.db.models.constants import LOOKUP_SEP
 from django.db.models.fields import FieldDoesNotExist
 from django.db.models.lookups import Lookup
 from django.db.models.sql.expressions import SQLEvaluator
+from django.utils import six
+
+gis_lookups = {}
 
 
 class GISLookup(Lookup):
+    sql_template = None
+    transform_func = None
+    distance = False
+
     @classmethod
     def _check_geo_field(cls, opts, lookup):
         """
@@ -45,10 +55,19 @@ class GISLookup(Lookup):
         else:
             return False
 
-    def as_sql(self, qn, connection):
-        # We use the same approach as was used by GeoWhereNode. It would
-        # be a good idea to upgrade GIS to use similar code that is used
-        # for other lookups.
+    def get_db_prep_lookup(self, value, connection):
+        # get_db_prep_lookup is called by process_rhs from super class
+        if isinstance(value, (tuple, list)):
+            # First param is assumed to be the geometric object
+            params = [connection.ops.Adapter(value[0])] + list(value)[1:]
+        else:
+            params = [connection.ops.Adapter(value)]
+        return ('%s', params)
+
+    def process_rhs(self, qn, connection):
+        rhs, rhs_params = super(GISLookup, self).process_rhs(qn, connection)
+
+        geom = self.rhs
         if isinstance(self.rhs, SQLEvaluator):
             # Make sure the F Expression destination field exists, and
             # set an `srid` attribute with the same as that of the
@@ -57,13 +76,256 @@ class GISLookup(Lookup):
             if not geo_fld:
                 raise ValueError('No geographic field found in expression.')
             self.rhs.srid = geo_fld.srid
-        db_type = self.lhs.output_field.db_type(connection=connection)
-        params = self.lhs.output_field.get_db_prep_lookup(
-            self.lookup_name, self.rhs, connection=connection)
-        lhs_sql, lhs_params = self.process_lhs(qn, connection)
-        # lhs_params not currently supported.
-        assert not lhs_params
-        data = (lhs_sql, db_type)
-        spatial_sql, spatial_params = connection.ops.spatial_lookup_sql(
-            data, self.lookup_name, self.rhs, self.lhs.output_field, qn)
-        return spatial_sql, spatial_params + params
+        elif isinstance(self.rhs, (list, tuple)):
+            geom = self.rhs[0]
+
+        rhs = connection.ops.get_geom_placeholder(self.lhs.source, geom)
+        return rhs, rhs_params
+
+    def as_sql(self, qn, connection):
+        lhs_sql, sql_params = self.process_lhs(qn, connection)
+        rhs_sql, rhs_params = self.process_rhs(qn, connection)
+        sql_params.extend(rhs_params)
+
+        template_params = {'lhs': lhs_sql, 'rhs': rhs_sql}
+        backend_op = connection.ops.gis_operators[self.lookup_name]
+        return backend_op.as_sql(connection, self, template_params, sql_params)
+
+
+# ------------------
+# Geometry operators
+# ------------------
+
+class OverlapsLeftLookup(GISLookup):
+    """
+    The overlaps_left operator returns true if A's bounding box overlaps or is to the
+    left of B's bounding box.
+    """
+    lookup_name = 'overlaps_left'
+gis_lookups['overlaps_left'] = OverlapsLeftLookup
+
+
+class OverlapsRightLookup(GISLookup):
+    """
+    The 'overlaps_right' operator returns true if A's bounding box overlaps or is to the
+    right of B's bounding box.
+    """
+    lookup_name = 'overlaps_right'
+gis_lookups['overlaps_right'] = OverlapsRightLookup
+
+
+class OverlapsBelowLookup(GISLookup):
+    """
+    The 'overlaps_below' operator returns true if A's bounding box overlaps or is below
+    B's bounding box.
+    """
+    lookup_name = 'overlaps_below'
+gis_lookups['overlaps_below'] = OverlapsBelowLookup
+
+
+class OverlapsAboveLookup(GISLookup):
+    """
+    The 'overlaps_above' operator returns true if A's bounding box overlaps or is above
+    B's bounding box.
+    """
+    lookup_name = 'overlaps_above'
+gis_lookups['overlaps_above'] = OverlapsAboveLookup
+
+
+class LeftLookup(GISLookup):
+    """
+    The 'left' operator returns true if A's bounding box is strictly to the left
+    of B's bounding box.
+    """
+    lookup_name = 'left'
+gis_lookups['left'] = LeftLookup
+
+
+class RightLookup(GISLookup):
+    """
+    The 'right' operator returns true if A's bounding box is strictly to the right
+    of B's bounding box.
+    """
+    lookup_name = 'right'
+gis_lookups['right'] = RightLookup
+
+
+class StrictlyBelowLookup(GISLookup):
+    """
+    The 'strictly_below' operator returns true if A's bounding box is strictly below B's
+    bounding box.
+    """
+    lookup_name = 'strictly_below'
+gis_lookups['strictly_below'] = StrictlyBelowLookup
+
+
+class StrictlyAboveLookup(GISLookup):
+    """
+    The 'strictly_above' operator returns true if A's bounding box is strictly above B's
+    bounding box.
+    """
+    lookup_name = 'strictly_above'
+gis_lookups['strictly_above'] = StrictlyAboveLookup
+
+
+class SameAsLookup(GISLookup):
+    """
+    The "~=" operator is the "same as" operator. It tests actual geometric
+    equality of two features. So if A and B are the same feature,
+    vertex-by-vertex, the operator returns true.
+    """
+    lookup_name = 'same_as'
+gis_lookups['same_as'] = SameAsLookup
+
+
+class ExactLookup(SameAsLookup):
+    # Alias of same_as
+    lookup_name = 'exact'
+gis_lookups['exact'] = ExactLookup
+
+
+class BBContainsLookup(GISLookup):
+    """
+    The 'bbcontains' operator returns true if A's bounding box completely contains
+    by B's bounding box.
+    """
+    lookup_name = 'bbcontains'
+gis_lookups['bbcontains'] = BBContainsLookup
+
+
+class BBOverlapsLookup(GISLookup):
+    """
+    The 'bboverlaps' operator returns true if A's bounding box overlaps B's bounding box.
+    """
+    lookup_name = 'bboverlaps'
+gis_lookups['bboverlaps'] = BBOverlapsLookup
+
+
+class ContainedLookup(GISLookup):
+    """
+    The 'contained' operator returns true if A's bounding box is completely contained
+    by B's bounding box.
+    """
+    lookup_name = 'contained'
+gis_lookups['contained'] = ContainedLookup
+
+
+# ------------------
+# Geometry functions
+# ------------------
+
+class ContainsLookup(GISLookup):
+    lookup_name = 'contains'
+gis_lookups['contains'] = ContainsLookup
+
+
+class ContainsProperlyLookup(GISLookup):
+    lookup_name = 'contains_properly'
+gis_lookups['contains_properly'] = ContainsProperlyLookup
+
+
+class CoveredByLookup(GISLookup):
+    lookup_name = 'coveredby'
+gis_lookups['coveredby'] = CoveredByLookup
+
+
+class CoversLookup(GISLookup):
+    lookup_name = 'covers'
+gis_lookups['covers'] = CoversLookup
+
+
+class CrossesLookup(GISLookup):
+    lookup_name = 'crosses'
+gis_lookups['crosses'] = CrossesLookup
+
+
+class DisjointLookup(GISLookup):
+    lookup_name = 'disjoint'
+gis_lookups['disjoint'] = DisjointLookup
+
+
+class EqualsLookup(GISLookup):
+    lookup_name = 'equals'
+gis_lookups['equals'] = EqualsLookup
+
+
+class IntersectsLookup(GISLookup):
+    lookup_name = 'intersects'
+gis_lookups['intersects'] = IntersectsLookup
+
+
+class OverlapsLookup(GISLookup):
+    lookup_name = 'overlaps'
+gis_lookups['overlaps'] = OverlapsLookup
+
+
+class RelateLookup(GISLookup):
+    lookup_name = 'relate'
+    sql_template = '%(func)s(%(lhs)s, %(rhs)s, %%s)'
+    pattern_regex = re.compile(r'^[012TF\*]{9}$')
+
+    def get_db_prep_lookup(self, value, connection):
+        if len(value) != 2:
+            raise ValueError('relate must be passed a two-tuple')
+        # Check the pattern argument
+        backend_op = connection.ops.gis_operators[self.lookup_name]
+        if hasattr(backend_op, 'check_relate_argument'):
+            backend_op.check_relate_argument(value[1])
+        else:
+            pattern = value[1]
+            if not isinstance(pattern, six.string_types) or not self.pattern_regex.match(pattern):
+                raise ValueError('Invalid intersection matrix pattern "%s".' % pattern)
+        return super(RelateLookup, self).get_db_prep_lookup(value, connection)
+gis_lookups['relate'] = RelateLookup
+
+
+class TouchesLookup(GISLookup):
+    lookup_name = 'touches'
+gis_lookups['touches'] = TouchesLookup
+
+
+class WithinLookup(GISLookup):
+    lookup_name = 'within'
+gis_lookups['within'] = WithinLookup
+
+
+class DistanceLookupBase(GISLookup):
+    distance = True
+    sql_template = '%(func)s(%(lhs)s, %(rhs)s) %(op)s %%s'
+
+    def get_db_prep_lookup(self, value, connection):
+        if isinstance(value, (tuple, list)):
+            if not 2 <= len(value) <= 3:
+                raise ValueError("2 or 3-element tuple required for '%s' lookup." % self.lookup_name)
+            params = [connection.ops.Adapter(value[0])]
+            # Getting the distance parameter in the units of the field.
+            params += connection.ops.get_distance(self.lhs.output_field, value[1:], self.lookup_name)
+            return ('%s', params)
+        else:
+            return super(DistanceLookupBase, self).get_db_prep_lookup(value, connection)
+
+
+class DWithinLookup(DistanceLookupBase):
+    lookup_name = 'dwithin'
+    sql_template = '%(func)s(%(lhs)s, %(rhs)s, %%s)'
+gis_lookups['dwithin'] = DWithinLookup
+
+
+class DistanceGTLookup(DistanceLookupBase):
+    lookup_name = 'distance_gt'
+gis_lookups['distance_gt'] = DistanceGTLookup
+
+
+class DistanceGTELookup(DistanceLookupBase):
+    lookup_name = 'distance_gte'
+gis_lookups['distance_gte'] = DistanceGTELookup
+
+
+class DistanceLTLookup(DistanceLookupBase):
+    lookup_name = 'distance_lt'
+gis_lookups['distance_lt'] = DistanceLTLookup
+
+
+class DistanceLTELookup(DistanceLookupBase):
+    lookup_name = 'distance_lte'
+gis_lookups['distance_lte'] = DistanceLTELookup
diff --git a/django/contrib/gis/db/models/sql/query.py b/django/contrib/gis/db/models/sql/query.py
index e82f17b8a3..d5a7f819c8 100644
--- a/django/contrib/gis/db/models/sql/query.py
+++ b/django/contrib/gis/db/models/sql/query.py
@@ -1,7 +1,7 @@
 from django.db import connections
 from django.db.models.query import sql
+from django.db.models.sql.constants import QUERY_TERMS
 
-from django.contrib.gis.db.models.constants import ALL_TERMS
 from django.contrib.gis.db.models.fields import GeometryField
 from django.contrib.gis.db.models.lookups import GISLookup
 from django.contrib.gis.db.models.sql import aggregates as gis_aggregates
@@ -13,7 +13,7 @@ class GeoQuery(sql.Query):
     A single spatial SQL query.
     """
     # Overridding the valid query terms.
-    query_terms = ALL_TERMS
+    query_terms = QUERY_TERMS | set(GeometryField.class_lookups.keys())
     aggregates_module = gis_aggregates
 
     compiler = 'GeoSQLCompiler'
diff --git a/docs/releases/1.8.txt b/docs/releases/1.8.txt
index 631b0bd2f0..db117e917e 100644
--- a/docs/releases/1.8.txt
+++ b/docs/releases/1.8.txt
@@ -612,6 +612,9 @@ Miscellaneous
   :func:`~django.core.urlresolvers.reverse_lazy` now return Unicode strings
   instead of byte strings.
 
+* GIS-specific lookups have been refactored to use the
+  :class:`django.db.models.Lookup` API.
+
 .. _deprecated-features-1.8:
 
 Features deprecated in 1.8