| from django.contrib.gis.gdal import OGRGeomType |
| from django.db.backends.sqlite3.introspection import DatabaseIntrospection, FlexibleFieldLookupDict |
| |
| class GeoFlexibleFieldLookupDict(FlexibleFieldLookupDict): |
| """ |
| Sublcass that includes updates the `base_data_types_reverse` dict |
| for geometry field types. |
| """ |
| base_data_types_reverse = FlexibleFieldLookupDict.base_data_types_reverse.copy() |
| base_data_types_reverse.update( |
| {'point' : 'GeometryField', |
| 'linestring' : 'GeometryField', |
| 'polygon' : 'GeometryField', |
| 'multipoint' : 'GeometryField', |
| 'multilinestring' : 'GeometryField', |
| 'multipolygon' : 'GeometryField', |
| 'geometrycollection' : 'GeometryField', |
| }) |
| |
| class SpatiaLiteIntrospection(DatabaseIntrospection): |
| data_types_reverse = GeoFlexibleFieldLookupDict() |
| |
| def get_geometry_type(self, table_name, geo_col): |
| cursor = self.connection.cursor() |
| try: |
| # Querying the `geometry_columns` table to get additional metadata. |
| cursor.execute('SELECT "coord_dimension", "srid", "type" ' |
| 'FROM "geometry_columns" ' |
| 'WHERE "f_table_name"=%s AND "f_geometry_column"=%s', |
| (table_name, geo_col)) |
| row = cursor.fetchone() |
| if not row: |
| raise Exception('Could not find a geometry column for "%s"."%s"' % |
| (table_name, geo_col)) |
| |
| # OGRGeomType does not require GDAL and makes it easy to convert |
| # from OGC geom type name to Django field. |
| field_type = OGRGeomType(row[2]).django |
| |
| # Getting any GeometryField keyword arguments that are not the default. |
| dim = row[0] |
| srid = row[1] |
| field_params = {} |
| if srid != 4326: |
| field_params['srid'] = srid |
| if isinstance(dim, basestring) and 'Z' in dim: |
| field_params['dim'] = 3 |
| finally: |
| cursor.close() |
| |
| return field_type, field_params |
