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gis: two big changes:

(1) the addition of the GeoMixin class, which gives geometry fields contributed functions (e.g. get_GEOM_area).
 (2) geo_filter() is no more, all queries use filter() now.


git-svn-id: http://code.djangoproject.com/svn/django/branches/gis@4884 bcc190cf-cafb-0310-a4f2-bffc1f526a37
This commit is contained in:
Justin Bronn 2007-03-31 21:25:29 +00:00
parent 0bf6355918
commit 8ef0b01e72
6 changed files with 59 additions and 38 deletions

View File

@ -0,0 +1,25 @@
# GEOS Routines
from django.contrib.gis.geos import hex_to_wkt, centroid, area
# Until model subclassing is a possibility, a mixin class is used to add
# the necessary functions that may be contributed for geographic objects.
class GeoMixin:
"The Geographic Mixin class, provides routines for geographic objects."
# A subclass of Model is specifically needed so that these geographic
# routines are present for instantiations of the models.
def _get_GEOM_wkt(self, field):
"Gets the WKT of the geometry."
hex = getattr(self, field.attname)
return hex_to_wkt(hex)
def _get_GEOM_centroid(self, field):
"Gets the centroid of the geometry, in WKT."
hex = getattr(self, field.attname)
return centroid(hex)
def _get_GEOM_area(self, field):
hex = getattr(self, field.attname)
return area(hex)

View File

@ -1,7 +1,7 @@
# Want to get everything from the 'normal' models package.
from django.db.models import *
# The GeoManager class.
# The GeoManager
from django.contrib.gis.db.models.manager import GeoManager
# The various PostGIS/OpenGIS enabled fields.
@ -10,3 +10,5 @@ from django.contrib.gis.db.models.fields import \
MultiPointField, MultiLineStringField, MultiPolygonField, \
GeometryCollectionField
# The geographic mixin class.
from GeoMixin import GeoMixin

View File

@ -1,8 +1,8 @@
# The Django base Field class.
from django.db.models.fields import Field
from django.oldforms import LargeTextField
from django.contrib.gis.db.models.postgis import POSTGIS_TERMS
from geos import geomToWKT, geomFromHEX
from django.contrib.gis.oldforms import WKTField
from django.utils.functional import curry
#TODO: add db.quotename.
@ -35,15 +35,6 @@ def _geom_index(geom, style, model, field,
style.SQL_KEYWORD(index_opts) + ' );'
return sql
class WKTField(LargeTextField):
"An oldforms LargeTextField for editing WKT text in the admin."
def render(self, data):
# PostGIS uses EWKBHEX to store its values internally, converting
# to WKT for the admin first.
wkt = geomToWKT(geomFromHEX(data))
return super(WKTField, self).render(wkt)
class GeometryField(Field):
"The base GIS field -- maps to the OpenGIS Geometry type."
@ -65,6 +56,14 @@ class GeometryField(Field):
super(GeometryField, self).__init__(**kwargs)
def contribute_to_class(self, cls, name):
super(GeometryField, self).contribute_to_class(cls, name)
# Adding the WKT accessor function for geometry
setattr(cls, 'get_%s_wkt' % self.name, curry(cls._get_GEOM_wkt, field=self))
setattr(cls, 'get_%s_centroid' % self.name, curry(cls._get_GEOM_centroid, field=self))
setattr(cls, 'get_%s_area' % self.name, curry(cls._get_GEOM_area, field=self))
def get_internal_type(self):
return "NoField"

View File

@ -2,12 +2,7 @@ from django.db.models.manager import Manager
from django.contrib.gis.db.models.query import GeoQuerySet
class GeoManager(Manager):
"Overrides Manager to return Geographic QuerySets."
def get_query_set(self):
return GeoQuerySet(model=self.model)
def geo_filter(self, *args, **kwargs):
return self.get_query_set().geo_filter(*args, **kwargs)
def geo_exclude(self, *args, **kwargs):
return self.get_query_set().geo_exclude(*args, **kwargs)

View File

@ -2,7 +2,7 @@
# django.db.models.query objects to be customized for PostGIS.
from copy import copy
from django.db import backend
from django.db.models.query import LOOKUP_SEPARATOR, find_field, FieldFound
from django.db.models.query import LOOKUP_SEPARATOR, find_field, FieldFound, QUERY_TERMS, get_where_clause
from django.utils.datastructures import SortedDict
# PostGIS-specific operators. The commented descriptions of these
@ -41,7 +41,6 @@ POSTGIS_GEOMETRY_FUNCTIONS = {
'distance' : 'Distance',
'equals' : 'Equals',
'disjoint' : 'Disjoint',
'intersects' : 'Intersects',
'touches' : 'Touches',
'crosses' : 'Crosses',
'within' : 'Within',
@ -55,6 +54,7 @@ POSTGIS_GEOMETRY_FUNCTIONS = {
# and the geometry functions.
POSTGIS_TERMS = list(POSTGIS_OPERATORS.keys()) # Getting the operators first
POSTGIS_TERMS.extend(list(POSTGIS_GEOMETRY_FUNCTIONS.keys())) # Adding on the Geometry Functions
POSTGIS_TERMS = tuple(POSTGIS_TERMS) # Making immutable
def get_geo_where_clause(lookup_type, table_prefix, field_name, value):
if table_prefix.endswith('.'):
@ -79,10 +79,10 @@ def get_geo_where_clause(lookup_type, table_prefix, field_name, value):
raise TypeError, "Got invalid lookup_type: %s" % repr(lookup_type)
def geo_parse_lookup(kwarg_items, opts):
def parse_lookup(kwarg_items, opts):
# Helper function that handles converting API kwargs
# (e.g. "name__exact": "tom") to SQL.
# Returns a tuple of (tables, joins, where, params).
# Returns a tuple of (joins, where, params).
# 'joins' is a sorted dictionary describing the tables that must be joined
# to complete the query. The dictionary is sorted because creation order
@ -112,10 +112,11 @@ def geo_parse_lookup(kwarg_items, opts):
# If there is only one part, or the last part is not a query
# term, assume that the query is an __exact
lookup_type = path.pop()
if lookup_type == 'pk':
lookup_type = 'exact'
path.append(None)
elif len(path) == 0 or lookup_type not in POSTGIS_TERMS:
elif len(path) == 0 or not ((lookup_type in QUERY_TERMS) or (lookup_type in POSTGIS_TERMS)):
path.append(lookup_type)
lookup_type = 'exact'
@ -200,6 +201,7 @@ def lookup_inner(path, lookup_type, value, opts, table, column):
# Does the name belong to a one-to-one, many-to-one, or regular field?
field = find_field(name, current_opts.fields, False)
if field:
if field.rel: # One-to-One/Many-to-one field
new_table = current_table + '__' + name
@ -293,8 +295,7 @@ def lookup_inner(path, lookup_type, value, opts, table, column):
if hasattr(field, '_geom'):
where.append(get_geo_where_clause(lookup_type, current_table + '.', column, value))
else:
raise TypeError, 'Field "%s" (%s) is not a Geometry Field.' % (column, field.__class__.__name__)
where.append(get_where_clause(lookup_type, current_table + '.', column, value))
params.extend(field.get_db_prep_lookup(lookup_type, value))
return joins, where, params

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@ -1,25 +1,24 @@
from django.db.models.query import *
from django.contrib.gis.db.models.postgis import geo_parse_lookup
from django.db.models.query import Q, QNot, QuerySet
from django.contrib.gis.db.models.postgis import parse_lookup
import operator
class GeoQ(Q):
"Geographical query encapsulation object."
def get_sql(self, opts):
"Overloaded to use the geo_parse_lookup() function instead of parse_lookup()"
return geo_parse_lookup(self.kwargs.items(), opts)
"Overloaded to use our own parse_lookup() function."
return parse_lookup(self.kwargs.items(), opts)
class GeoQuerySet(QuerySet):
"Geographical-enabled QuerySet object."
def geo_filter(self, *args, **kwargs):
"Returns a new GeoQuerySet instance with the args ANDed to the existing set."
return self._geo_filter_or_exclude(None, *args, **kwargs)
def __init__(self, model=None):
super(GeoQuerySet, self).__init__(model=model)
def geo_exclude(self, *args, **kwargs):
"Returns a new GeoQuerySet instance with NOT (args) ANDed to the existing set."
return self._geo_filter_or_exclude(QNot, *args, **kwargs)
# We only want to use the GeoQ object for our queries
self._filters = GeoQ()
def _geo_filter_or_exclude(self, mapper, *args, **kwargs):
def _filter_or_exclude(self, mapper, *args, **kwargs):
# mapper is a callable used to transform Q objects,
# or None for identity transform
if mapper is None: