blinkster: comparison web/lib/django/contrib/gis/db/models/query.py

equal deleted inserted replaced

-:8d941af65caf
+:77b6da96e6f1
+from django.db import connections
+from django.db.models.query import QuerySet, Q, ValuesQuerySet, ValuesListQuerySet
+from django.contrib.gis.db.models import aggregates
+from django.contrib.gis.db.models.fields import get_srid_info, GeometryField, PointField, LineStringField
+from django.contrib.gis.db.models.sql import AreaField, DistanceField, GeomField, GeoQuery, GeoWhereNode
+from django.contrib.gis.geometry.backend import Geometry
+from django.contrib.gis.measure import Area, Distance
+class GeoQuerySet(QuerySet):
+"The Geographic QuerySet."
+### Methods overloaded from QuerySet ###
+def __init__(self, model=None, query=None, using=None):
+super(GeoQuerySet, self).__init__(model=model, query=query, using=using)
+self.query = query or GeoQuery(self.model)
+def values(self, *fields):
+return self._clone(klass=GeoValuesQuerySet, setup=True, _fields=fields)
+def values_list(self, *fields, **kwargs):
+flat = kwargs.pop('flat', False)
+if kwargs:
+raise TypeError('Unexpected keyword arguments to values_list: %s'
+% (kwargs.keys(),))
+if flat and len(fields) > 1:
+raise TypeError("'flat' is not valid when values_list is called with more than one field.")
+return self._clone(klass=GeoValuesListQuerySet, setup=True, flat=flat,
+_fields=fields)
+### GeoQuerySet Methods ###
+def area(self, tolerance=0.05, **kwargs):
+"""
+Returns the area of the geographic field in an `area` attribute on
+each element of this GeoQuerySet.
+"""
+# Peforming setup here rather than in `_spatial_attribute` so that
+# we can get the units for `AreaField`.
+procedure_args, geo_field = self._spatial_setup('area', field_name=kwargs.get('field_name', None))
+s = {'procedure_args' : procedure_args,
+'geo_field' : geo_field,
+'setup' : False,
+}
+connection = connections[self.db]
+backend = connection.ops
+if backend.oracle:
+s['procedure_fmt'] = '%(geo_col)s,%(tolerance)s'
+s['procedure_args']['tolerance'] = tolerance
+s['select_field'] = AreaField('sq_m') # Oracle returns area in units of meters.
+elif backend.postgis or backend.spatialite:
+if not geo_field.geodetic(connection):
+# Getting the area units of the geographic field.
+s['select_field'] = AreaField(Area.unit_attname(geo_field.units_name(connection)))
+else:
+# TODO: Do we want to support raw number areas for geodetic fields?
+raise Exception('Area on geodetic coordinate systems not supported.')
+return self._spatial_attribute('area', s, **kwargs)
+def centroid(self, **kwargs):
+"""
+Returns the centroid of the geographic field in a `centroid`
+attribute on each element of this GeoQuerySet.
+"""
+return self._geom_attribute('centroid', **kwargs)
+def collect(self, **kwargs):
+"""
+Performs an aggregate collect operation on the given geometry field.
+This is analagous to a union operation, but much faster because
+boundaries are not dissolved.
+"""
+return self._spatial_aggregate(aggregates.Collect, **kwargs)
+def difference(self, geom, **kwargs):
+"""
+Returns the spatial difference of the geographic field in a `difference`
+attribute on each element of this GeoQuerySet.
+"""
+return self._geomset_attribute('difference', geom, **kwargs)
+def distance(self, geom, **kwargs):
+"""
+Returns the distance from the given geographic field name to the
+given geometry in a `distance` attribute on each element of the
+GeoQuerySet.
+Keyword Arguments:
+`spheroid`  => If the geometry field is geodetic and PostGIS is
+the spatial database, then the more accurate
+spheroid calculation will be used instead of the
+quicker sphere calculation.
+`tolerance` => Used only for Oracle. The tolerance is
+in meters -- a default of 5 centimeters (0.05)
+is used.
+"""
+return self._distance_attribute('distance', geom, **kwargs)
+def envelope(self, **kwargs):
+"""
+Returns a Geometry representing the bounding box of the
+Geometry field in an `envelope` attribute on each element of
+the GeoQuerySet.
+"""
+return self._geom_attribute('envelope', **kwargs)
+def extent(self, **kwargs):
+"""
+Returns the extent (aggregate) of the features in the GeoQuerySet.  The
+extent will be returned as a 4-tuple, consisting of (xmin, ymin, xmax, ymax).
+"""
+return self._spatial_aggregate(aggregates.Extent, **kwargs)
+def extent3d(self, **kwargs):
+"""
+Returns the aggregate extent, in 3D, of the features in the
+GeoQuerySet. It is returned as a 6-tuple, comprising:
+(xmin, ymin, zmin, xmax, ymax, zmax).
+"""
+return self._spatial_aggregate(aggregates.Extent3D, **kwargs)
+def force_rhr(self, **kwargs):
+"""
+Returns a modified version of the Polygon/MultiPolygon in which
+all of the vertices follow the Right-Hand-Rule.  By default,
+this is attached as the `force_rhr` attribute on each element
+of the GeoQuerySet.
+"""
+return self._geom_attribute('force_rhr', **kwargs)
+def geojson(self, precision=8, crs=False, bbox=False, **kwargs):
+"""
+Returns a GeoJSON representation of the geomtry field in a `geojson`
+attribute on each element of the GeoQuerySet.
+The `crs` and `bbox` keywords may be set to True if the users wants
+the coordinate reference system and the bounding box to be included
+in the GeoJSON representation of the geometry.
+"""
+backend = connections[self.db].ops
+if not backend.geojson:
+raise NotImplementedError('Only PostGIS 1.3.4+ supports GeoJSON serialization.')
+if not isinstance(precision, (int, long)):
+raise TypeError('Precision keyword must be set with an integer.')
+# Setting the options flag -- which depends on which version of
+# PostGIS we're using.
+if backend.spatial_version >= (1, 4, 0):
+options = 0
+if crs and bbox: options = 3
+elif bbox: options = 1
+elif crs: options = 2
+else:
+options = 0
+if crs and bbox: options = 3
+elif crs: options = 1
+elif bbox: options = 2
+s = {'desc' : 'GeoJSON',
+'procedure_args' : {'precision' : precision, 'options' : options},
+'procedure_fmt' : '%(geo_col)s,%(precision)s,%(options)s',
+}
+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
+on each element of the GeoQuerySet.
+"""
+backend = connections[self.db].ops
+s = {'desc' : 'GML', 'procedure_args' : {'precision' : precision}}
+if backend.postgis:
+# PostGIS AsGML() aggregate function parameter order depends on the
+# version -- uggh.
+if backend.spatial_version > (1, 3, 1):
+procedure_fmt = '%(version)s,%(geo_col)s,%(precision)s'
+else:
+procedure_fmt = '%(geo_col)s,%(precision)s,%(version)s'
+s['procedure_args'] = {'precision' : precision, 'version' : version}
+return self._spatial_attribute('gml', s, **kwargs)
+def intersection(self, geom, **kwargs):
+"""
+Returns the spatial intersection of the Geometry field in
+an `intersection` attribute on each element of this
+GeoQuerySet.
+"""
+return self._geomset_attribute('intersection', geom, **kwargs)
+def kml(self, **kwargs):
+"""
+Returns KML representation of the geometry field in a `kml`
+attribute on each element of this GeoQuerySet.
+"""
+s = {'desc' : 'KML',
+'procedure_fmt' : '%(geo_col)s,%(precision)s',
+'procedure_args' : {'precision' : kwargs.pop('precision', 8)},
+}
+return self._spatial_attribute('kml', s, **kwargs)
+def length(self, **kwargs):
+"""
+Returns the length of the geometry field as a `Distance` object
+stored in a `length` attribute on each element of this GeoQuerySet.
+"""
+return self._distance_attribute('length', None, **kwargs)
+def make_line(self, **kwargs):
+"""
+Creates a linestring from all of the PointField geometries in the
+this GeoQuerySet and returns it.  This is a spatial aggregate
+method, and thus returns a geometry rather than a GeoQuerySet.
+"""
+return self._spatial_aggregate(aggregates.MakeLine, geo_field_type=PointField, **kwargs)
+def mem_size(self, **kwargs):
+"""
+Returns the memory size (number of bytes) that the geometry field takes
+in a `mem_size` attribute  on each element of this GeoQuerySet.
+"""
+return self._spatial_attribute('mem_size', {}, **kwargs)
+def num_geom(self, **kwargs):
+"""
+Returns the number of geometries if the field is a
+GeometryCollection or Multi* Field in a `num_geom`
+attribute on each element of this GeoQuerySet; otherwise
+the sets with None.
+"""
+return self._spatial_attribute('num_geom', {}, **kwargs)
+def num_points(self, **kwargs):
+"""
+Returns the number of points in the first linestring in the
+Geometry field in a `num_points` attribute on each element of
+this GeoQuerySet; otherwise sets with None.
+"""
+return self._spatial_attribute('num_points', {}, **kwargs)
+def perimeter(self, **kwargs):
+"""
+Returns the perimeter of the geometry field as a `Distance` object
+stored in a `perimeter` attribute on each element of this GeoQuerySet.
+"""
+return self._distance_attribute('perimeter', None, **kwargs)
+def point_on_surface(self, **kwargs):
+"""
+Returns a Point geometry guaranteed to lie on the surface of the
+Geometry field in a `point_on_surface` attribute on each element
+of this GeoQuerySet; otherwise sets with None.
+"""
+return self._geom_attribute('point_on_surface', **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)
+def scale(self, x, y, z=0.0, **kwargs):
+"""
+Scales the geometry to a new size by multiplying the ordinates
+with the given x,y,z scale factors.
+"""
+if connections[self.db].ops.spatialite:
+if z != 0.0:
+raise NotImplementedError('SpatiaLite does not support 3D scaling.')
+s = {'procedure_fmt' : '%(geo_col)s,%(x)s,%(y)s',
+'procedure_args' : {'x' : x, 'y' : y},
+'select_field' : GeomField(),
+}
+else:
+s = {'procedure_fmt' : '%(geo_col)s,%(x)s,%(y)s,%(z)s',
+'procedure_args' : {'x' : x, 'y' : y, 'z' : z},
+'select_field' : GeomField(),
+}
+return self._spatial_attribute('scale', s, **kwargs)
+def snap_to_grid(self, *args, **kwargs):
+"""
+Snap all points of the input geometry to the grid.  How the
+geometry is snapped to the grid depends on how many arguments
+were given:
+- 1 argument : A single size to snap both the X and Y grids to.
+- 2 arguments: X and Y sizes to snap the grid to.
+- 4 arguments: X, Y sizes and the X, Y origins.
+"""
+if False in [isinstance(arg, (float, int, long)) for arg in args]:
+raise TypeError('Size argument(s) for the grid must be a float or integer values.')
+nargs = len(args)
+if nargs == 1:
+size = args[0]
+procedure_fmt = '%(geo_col)s,%(size)s'
+procedure_args = {'size' : size}
+elif nargs == 2:
+xsize, ysize = args
+procedure_fmt = '%(geo_col)s,%(xsize)s,%(ysize)s'
+procedure_args = {'xsize' : xsize, 'ysize' : ysize}
+elif nargs == 4:
+xsize, ysize, xorigin, yorigin = args
+procedure_fmt = '%(geo_col)s,%(xorigin)s,%(yorigin)s,%(xsize)s,%(ysize)s'
+procedure_args = {'xsize' : xsize, 'ysize' : ysize,
+'xorigin' : xorigin, 'yorigin' : yorigin}
+else:
+raise ValueError('Must provide 1, 2, or 4 arguments to `snap_to_grid`.')
+s = {'procedure_fmt' : procedure_fmt,
+'procedure_args' : procedure_args,
+'select_field' : GeomField(),
+}
+return self._spatial_attribute('snap_to_grid', s, **kwargs)
+def svg(self, relative=False, precision=8, **kwargs):
+"""
+Returns SVG representation of the geographic field in a `svg`
+attribute on each element of this GeoQuerySet.
+Keyword Arguments:
+`relative`  => If set to True, this will evaluate the path in
+terms of relative moves (rather than absolute).
+`precision` => May be used to set the maximum number of decimal
+digits used in output (defaults to 8).
+"""
+relative = int(bool(relative))
+if not isinstance(precision, (int, long)):
+raise TypeError('SVG precision keyword argument must be an integer.')
+s = {'desc' : 'SVG',
+'procedure_fmt' : '%(geo_col)s,%(rel)s,%(precision)s',
+'procedure_args' : {'rel' : relative,
+'precision' : precision,
+}
+}
+return self._spatial_attribute('svg', s, **kwargs)
+def sym_difference(self, geom, **kwargs):
+"""
+Returns the symmetric difference of the geographic field in a
+`sym_difference` attribute on each element of this GeoQuerySet.
+"""
+return self._geomset_attribute('sym_difference', geom, **kwargs)
+def translate(self, x, y, z=0.0, **kwargs):
+"""
+Translates the geometry to a new location using the given numeric
+parameters as offsets.
+"""
+if connections[self.db].ops.spatialite:
+if z != 0.0:
+raise NotImplementedError('SpatiaLite does not support 3D translation.')
+s = {'procedure_fmt' : '%(geo_col)s,%(x)s,%(y)s',
+'procedure_args' : {'x' : x, 'y' : y},
+'select_field' : GeomField(),
+}
+else:
+s = {'procedure_fmt' : '%(geo_col)s,%(x)s,%(y)s,%(z)s',
+'procedure_args' : {'x' : x, 'y' : y, 'z' : z},
+'select_field' : GeomField(),
+}
+return self._spatial_attribute('translate', s, **kwargs)
+def transform(self, srid=4326, **kwargs):
+"""
+Transforms the given geometry field to the given SRID.  If no SRID is
+provided, the transformation will default to using 4326 (WGS84).
+"""
+if not isinstance(srid, (int, long)):
+raise TypeError('An integer SRID must be provided.')
+field_name = kwargs.get('field_name', None)
+tmp, geo_field = self._spatial_setup('transform', field_name=field_name)
+# Getting the selection SQL for the given geographic field.
+field_col = self._geocol_select(geo_field, field_name)
+# Why cascading substitutions? Because spatial backends like
+# Oracle and MySQL already require a function call to convert to text, thus
+# when there's also a transformation we need to cascade the substitutions.
+# For example, 'SDO_UTIL.TO_WKTGEOMETRY(SDO_CS.TRANSFORM( ... )'
+geo_col = self.query.custom_select.get(geo_field, field_col)
+# Setting the key for the field's column with the custom SELECT SQL to
+# override the geometry column returned from the database.
+custom_sel = '%s(%s, %s)' % (connections[self.db].ops.transform, geo_col, srid)
+# TODO: Should we have this as an alias?
+# custom_sel = '(%s(%s, %s)) AS %s' % (SpatialBackend.transform, geo_col, srid, qn(geo_field.name))
+self.query.transformed_srid = srid # So other GeoQuerySet methods
+self.query.custom_select[geo_field] = custom_sel
+return self._clone()
+def union(self, geom, **kwargs):
+"""
+Returns the union of the geographic field with the given
+Geometry in a `union` attribute on each element of this GeoQuerySet.
+"""
+return self._geomset_attribute('union', geom, **kwargs)
+def unionagg(self, **kwargs):
+"""
+Performs an aggregate union on the given geometry field.  Returns
+None if the GeoQuerySet is empty.  The `tolerance` keyword is for
+Oracle backends only.
+"""
+return self._spatial_aggregate(aggregates.Union, **kwargs)
+### Private API -- Abstracted DRY routines. ###
+def _spatial_setup(self, att, desc=None, field_name=None, geo_field_type=None):
+"""
+Performs set up for executing the spatial function.
+"""
+# Does the spatial backend support this?
+connection = connections[self.db]
+func = getattr(connection.ops, att, False)
+if desc is None: desc = att
+if not func:
+raise NotImplementedError('%s stored procedure not available on '
+'the %s backend.' %
+(desc, connection.ops.name))
+# Initializing the procedure arguments.
+procedure_args = {'function' : func}
+# Is there a geographic field in the model to perform this
+# operation on?
+geo_field = self.query._geo_field(field_name)
+if not geo_field:
+raise TypeError('%s output only available on GeometryFields.' % func)
+# If the `geo_field_type` keyword was used, then enforce that
+# type limitation.
+if not geo_field_type is None and not isinstance(geo_field, geo_field_type):
+raise TypeError('"%s" stored procedures may only be called on %ss.' % (func, geo_field_type.__name__))
+# Setting the procedure args.
+procedure_args['geo_col'] = self._geocol_select(geo_field, field_name)
+return procedure_args, geo_field
+def _spatial_aggregate(self, aggregate, field_name=None,
+geo_field_type=None, tolerance=0.05):
+"""
+DRY routine for calling aggregate spatial stored procedures and
+returning their result to the caller of the function.
+"""
+# Getting the field the geographic aggregate will be called on.
+geo_field = self.query._geo_field(field_name)
+if not geo_field:
+raise TypeError('%s aggregate only available on GeometryFields.' % aggregate.name)
+# Checking if there are any geo field type limitations on this
+# aggregate (e.g. ST_Makeline only operates on PointFields).
+if not geo_field_type is None and not isinstance(geo_field, geo_field_type):
+raise TypeError('%s aggregate may only be called on %ss.' % (aggregate.name, geo_field_type.__name__))
+# Getting the string expression of the field name, as this is the
+# argument taken by `Aggregate` objects.
+agg_col = field_name or geo_field.name
+# Adding any keyword parameters for the Aggregate object. Oracle backends
+# in particular need an additional `tolerance` parameter.
+agg_kwargs = {}
+if connections[self.db].ops.oracle: agg_kwargs['tolerance'] = tolerance
+# Calling the QuerySet.aggregate, and returning only the value of the aggregate.
+return self.aggregate(geoagg=aggregate(agg_col, **agg_kwargs))['geoagg']
+def _spatial_attribute(self, att, settings, field_name=None, model_att=None):
+"""
+DRY routine for calling a spatial stored procedure on a geometry column
+and attaching its output as an attribute of the model.
+Arguments:
+att:
+The name of the spatial attribute that holds the spatial
+SQL function to call.
+settings:
+Dictonary of internal settings to customize for the spatial procedure.
+Public Keyword Arguments:
+field_name:
+The name of the geographic field to call the spatial
+function on.  May also be a lookup to a geometry field
+as part of a foreign key relation.
+model_att:
+The name of the model attribute to attach the output of
+the spatial function to.
+"""
+# Default settings.
+settings.setdefault('desc', None)
+settings.setdefault('geom_args', ())
+settings.setdefault('geom_field', None)
+settings.setdefault('procedure_args', {})
+settings.setdefault('procedure_fmt', '%(geo_col)s')
+settings.setdefault('select_params', [])
+connection = connections[self.db]
+backend = connection.ops
+# Performing setup for the spatial column, unless told not to.
+if settings.get('setup', True):
+default_args, geo_field = self._spatial_setup(att, desc=settings['desc'], field_name=field_name,
+geo_field_type=settings.get('geo_field_type', None))
+for k, v in default_args.iteritems(): settings['procedure_args'].setdefault(k, v)
+else:
+geo_field = settings['geo_field']
+# The attribute to attach to the model.
+if not isinstance(model_att, basestring): model_att = att
+# Special handling for any argument that is a geometry.
+for name in settings['geom_args']:
+# Using the field's get_placeholder() routine to get any needed
+# transformation SQL.
+geom = geo_field.get_prep_value(settings['procedure_args'][name])
+params = geo_field.get_db_prep_lookup('contains', geom, connection=connection)
+geom_placeholder = geo_field.get_placeholder(geom, connection)
+# Replacing the procedure format with that of any needed
+# transformation SQL.
+old_fmt = '%%(%s)s' % name
+new_fmt = geom_placeholder % '%%s'
+settings['procedure_fmt'] = settings['procedure_fmt'].replace(old_fmt, new_fmt)
+settings['select_params'].extend(params)
+# Getting the format for the stored procedure.
+fmt = '%%(function)s(%s)' % settings['procedure_fmt']
+# If the result of this function needs to be converted.
+if settings.get('select_field', False):
+sel_fld = settings['select_field']
+if isinstance(sel_fld, GeomField) and backend.select:
+self.query.custom_select[model_att] = backend.select
+if connection.ops.oracle:
+sel_fld.empty_strings_allowed = False
+self.query.extra_select_fields[model_att] = sel_fld
+# Finally, setting the extra selection attribute with
+# the format string expanded with the stored procedure
+# arguments.
+return self.extra(select={model_att : fmt % settings['procedure_args']},
+select_params=settings['select_params'])
+def _distance_attribute(self, func, geom=None, tolerance=0.05, spheroid=False, **kwargs):
+"""
+DRY routine for GeoQuerySet distance attribute routines.
+"""
+# Setting up the distance procedure arguments.
+procedure_args, geo_field = self._spatial_setup(func, field_name=kwargs.get('field_name', None))
+# If geodetic defaulting distance attribute to meters (Oracle and
+# PostGIS spherical distances return meters).  Otherwise, use the
+# units of the geometry field.
+connection = connections[self.db]
+geodetic = geo_field.geodetic(connection)
+geography = geo_field.geography
+if geodetic:
+dist_att = 'm'
+else:
+dist_att = Distance.unit_attname(geo_field.units_name(connection))
+# Shortcut booleans for what distance function we're using and
+# whether the geometry field is 3D.
+distance = func == 'distance'
+length = func == 'length'
+perimeter = func == 'perimeter'
+if not (distance or length or perimeter):
+raise ValueError('Unknown distance function: %s' % func)
+geom_3d = geo_field.dim == 3
+# The field's get_db_prep_lookup() is used to get any
+# extra distance parameters.  Here we set up the
+# parameters that will be passed in to field's function.
+lookup_params = [geom or 'POINT (0 0)', 0]
+# Getting the spatial backend operations.
+backend = connection.ops
+# If the spheroid calculation is desired, either by the `spheroid`
+# keyword or when calculating the length of geodetic field, make
+# sure the 'spheroid' distance setting string is passed in so we
+# get the correct spatial stored procedure.
+if spheroid or (backend.postgis and geodetic and
+(not geography) and length):
+lookup_params.append('spheroid')
+lookup_params = geo_field.get_prep_value(lookup_params)
+params = geo_field.get_db_prep_lookup('distance_lte', lookup_params, connection=connection)
+# The `geom_args` flag is set to true if a geometry parameter was
+# passed in.
+geom_args = bool(geom)
+if backend.oracle:
+if distance:
+procedure_fmt = '%(geo_col)s,%(geom)s,%(tolerance)s'
+elif length or perimeter:
+procedure_fmt = '%(geo_col)s,%(tolerance)s'
+procedure_args['tolerance'] = tolerance
+else:
+# Getting whether this field is in units of degrees since the field may have
+# been transformed via the `transform` GeoQuerySet method.
+if self.query.transformed_srid:
+u, unit_name, s = get_srid_info(self.query.transformed_srid, connection)
+geodetic = unit_name in geo_field.geodetic_units
+if backend.spatialite and geodetic:
+raise ValueError('SQLite does not support linear distance calculations on geodetic coordinate systems.')
+if distance:
+if self.query.transformed_srid:
+# Setting the `geom_args` flag to false because we want to handle
+# transformation SQL here, rather than the way done by default
+# (which will transform to the original SRID of the field rather
+#  than to what was transformed to).
+geom_args = False
+procedure_fmt = '%s(%%(geo_col)s, %s)' % (backend.transform, self.query.transformed_srid)
+if geom.srid is None or geom.srid == self.query.transformed_srid:
+# If the geom parameter srid is None, it is assumed the coordinates
+# are in the transformed units.  A placeholder is used for the
+# geometry parameter.  `GeomFromText` constructor is also needed
+# to wrap geom placeholder for SpatiaLite.
+if backend.spatialite:
+procedure_fmt += ', %s(%%%%s, %s)' % (backend.from_text, self.query.transformed_srid)
+else:
+procedure_fmt += ', %%s'
+else:
+# We need to transform the geom to the srid specified in `transform()`,
+# so wrapping the geometry placeholder in transformation SQL.
+# SpatiaLite also needs geometry placeholder wrapped in `GeomFromText`
+# constructor.
+if backend.spatialite:
+procedure_fmt += ', %s(%s(%%%%s, %s), %s)' % (backend.transform, backend.from_text,
+geom.srid, self.query.transformed_srid)
+else:
+procedure_fmt += ', %s(%%%%s, %s)' % (backend.transform, self.query.transformed_srid)
+else:
+# `transform()` was not used on this GeoQuerySet.
+procedure_fmt  = '%(geo_col)s,%(geom)s'
+if not geography and geodetic:
+# Spherical distance calculation is needed (because the geographic
+# field is geodetic). However, the PostGIS ST_distance_sphere/spheroid()
+# procedures may only do queries from point columns to point geometries
+# some error checking is required.
+if not backend.geography:
+if not isinstance(geo_field, PointField):
+raise ValueError('Spherical distance calculation only supported on PointFields.')
+if not str(Geometry(buffer(params[0].ewkb)).geom_type) == 'Point':
+raise ValueError('Spherical distance calculation only supported with Point Geometry parameters')
+# The `function` procedure argument needs to be set differently for
+# geodetic distance calculations.
+if spheroid:
+# Call to distance_spheroid() requires spheroid param as well.
+procedure_fmt += ",'%(spheroid)s'"
+procedure_args.update({'function' : backend.distance_spheroid, 'spheroid' : params[1]})
+else:
+procedure_args.update({'function' : backend.distance_sphere})
+elif length or perimeter:
+procedure_fmt = '%(geo_col)s'
+if not geography and geodetic and length:
+# There's no `length_sphere`, and `length_spheroid` also
+# works on 3D geometries.
+procedure_fmt += ",'%(spheroid)s'"
+procedure_args.update({'function' : backend.length_spheroid, 'spheroid' : params[1]})
+elif geom_3d and backend.postgis:
+# Use 3D variants of perimeter and length routines on PostGIS.
+if perimeter:
+procedure_args.update({'function' : backend.perimeter3d})
+elif length:
+procedure_args.update({'function' : backend.length3d})
+# Setting up the settings for `_spatial_attribute`.
+s = {'select_field' : DistanceField(dist_att),
+'setup' : False,
+'geo_field' : geo_field,
+'procedure_args' : procedure_args,
+'procedure_fmt' : procedure_fmt,
+}
+if geom_args:
+s['geom_args'] = ('geom',)
+s['procedure_args']['geom'] = geom
+elif geom:
+# The geometry is passed in as a parameter because we handled
+# transformation conditions in this routine.
+s['select_params'] = [backend.Adapter(geom)]
+return self._spatial_attribute(func, s, **kwargs)
+def _geom_attribute(self, func, tolerance=0.05, **kwargs):
+"""
+DRY routine for setting up a GeoQuerySet method that attaches a
+Geometry attribute (e.g., `centroid`, `point_on_surface`).
+"""
+s = {'select_field' : GeomField(),}
+if connections[self.db].ops.oracle:
+s['procedure_fmt'] = '%(geo_col)s,%(tolerance)s'
+s['procedure_args'] = {'tolerance' : tolerance}
+return self._spatial_attribute(func, s, **kwargs)
+def _geomset_attribute(self, func, geom, tolerance=0.05, **kwargs):
+"""
+DRY routine for setting up a GeoQuerySet method that attaches a
+Geometry attribute and takes a Geoemtry parameter.  This is used
+for geometry set-like operations (e.g., intersection, difference,
+union, sym_difference).
+"""
+s = {'geom_args' : ('geom',),
+'select_field' : GeomField(),
+'procedure_fmt' : '%(geo_col)s,%(geom)s',
+'procedure_args' : {'geom' : geom},
+}
+if connections[self.db].ops.oracle:
+s['procedure_fmt'] += ',%(tolerance)s'
+s['procedure_args']['tolerance'] = tolerance
+return self._spatial_attribute(func, s, **kwargs)
+def _geocol_select(self, geo_field, field_name):
+"""
+Helper routine for constructing the SQL to select the geographic
+column.  Takes into account if the geographic field is in a
+ForeignKey relation to the current model.
+"""
+opts = self.model._meta
+if not geo_field in opts.fields:
+# Is this operation going to be on a related geographic field?
+# If so, it'll have to be added to the select related information
+# (e.g., if 'location__point' was given as the field name).
+self.query.add_select_related([field_name])
+compiler = self.query.get_compiler(self.db)
+compiler.pre_sql_setup()
+rel_table, rel_col = self.query.related_select_cols[self.query.related_select_fields.index(geo_field)]
+return compiler._field_column(geo_field, rel_table)
+elif not geo_field in opts.local_fields:
+# This geographic field is inherited from another model, so we have to
+# use the db table for the _parent_ model instead.
+tmp_fld, parent_model, direct, m2m = opts.get_field_by_name(geo_field.name)
+return self.query.get_compiler(self.db)._field_column(geo_field, parent_model._meta.db_table)
+else:
+return self.query.get_compiler(self.db)._field_column(geo_field)
+class GeoValuesQuerySet(ValuesQuerySet):
+def __init__(self, *args, **kwargs):
+super(GeoValuesQuerySet, self).__init__(*args, **kwargs)
+# This flag tells `resolve_columns` to run the values through
+# `convert_values`.  This ensures that Geometry objects instead
+# of string values are returned with `values()` or `values_list()`.
+self.query.geo_values = True
+class GeoValuesListQuerySet(GeoValuesQuerySet, ValuesListQuerySet):
+pass