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Diffstat (limited to 'lib/python2.7/site-packages/django/contrib/gis/db/backends/base.py')
| -rw-r--r-- | lib/python2.7/site-packages/django/contrib/gis/db/backends/base.py | 349 |
1 files changed, 0 insertions, 349 deletions
diff --git a/lib/python2.7/site-packages/django/contrib/gis/db/backends/base.py b/lib/python2.7/site-packages/django/contrib/gis/db/backends/base.py deleted file mode 100644 index 7db7ce5..0000000 --- a/lib/python2.7/site-packages/django/contrib/gis/db/backends/base.py +++ /dev/null @@ -1,349 +0,0 @@ -""" -Base/mixin classes for the spatial backend database operations and the -`SpatialRefSys` model the backend. -""" -import re - -from django.contrib.gis import gdal -from django.utils import six -from django.utils.encoding import python_2_unicode_compatible - - -class BaseSpatialOperations(object): - """ - This module holds the base `BaseSpatialBackend` object, which is - 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 - # an attribute for the spatial database version tuple (if applicable) - postgis = False - spatialite = False - mysql = False - oracle = False - spatial_version = None - - # How the geometry column should be selected. - select = None - - # Does the spatial database have a geometry or geography type? - geography = False - geometry = False - - area = False - centroid = False - difference = False - distance = False - distance_sphere = False - distance_spheroid = False - envelope = False - force_rhr = False - mem_size = False - bounding_circle = False - num_geom = False - num_points = False - perimeter = False - perimeter3d = False - point_on_surface = False - polygonize = False - reverse = False - scale = False - snap_to_grid = False - sym_difference = False - transform = False - translate = False - union = False - - # Aggregates - collect = False - extent = False - extent3d = False - make_line = False - unionagg = False - - # Serialization - geohash = False - geojson = False - gml = False - kml = False - svg = False - - # Constructors - from_text = False - from_wkb = False - - # Default conversion functions for aggregates; will be overridden if implemented - # for the spatial backend. - def convert_extent(self, box): - raise NotImplementedError('Aggregate extent not implemented for this spatial backend.') - - def convert_extent3d(self, box): - raise NotImplementedError('Aggregate 3D extent not implemented for this spatial backend.') - - def convert_geom(self, geom_val, geom_field): - raise NotImplementedError('Aggregate method not implemented for this spatial backend.') - - # For quoting column values, rather than columns. - def geo_quote_name(self, name): - return "'%s'" % name - - # GeometryField operations - def geo_db_type(self, f): - """ - Returns the database column type for the geometry field on - the spatial backend. - """ - raise NotImplementedError - - def get_distance(self, f, value, lookup_type): - """ - Returns the distance parameters for the given geometry field, - lookup value, and lookup type. - """ - raise NotImplementedError('Distance operations not available on this spatial backend.') - - def get_geom_placeholder(self, f, value): - """ - Returns the placeholder for the given geometry field with the given - value. Depending on the spatial backend, the placeholder may contain a - stored procedure call to the transformation function of the spatial - backend. - """ - raise NotImplementedError - - def get_expression_column(self, evaluator): - """ - Helper method to return the quoted column string from the evaluator - for its expression. - """ - for expr, col_tup in evaluator.cols: - if expr is evaluator.expression: - return '%s.%s' % tuple(map(self.quote_name, col_tup)) - raise Exception("Could not find the column for the expression.") - - # Spatial SQL Construction - 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 - - # Routines for getting the OGC-compliant models. - def geometry_columns(self): - raise NotImplementedError - - def spatial_ref_sys(self): - raise NotImplementedError - -@python_2_unicode_compatible -class SpatialRefSysMixin(object): - """ - The SpatialRefSysMixin is a class used by the database-dependent - SpatialRefSys objects to reduce redundnant code. - """ - # For pulling out the spheroid from the spatial reference string. This - # regular expression is used only if the user does not have GDAL installed. - # TODO: Flattening not used in all ellipsoids, could also be a minor axis, - # or 'b' parameter. - spheroid_regex = re.compile(r'.+SPHEROID\[\"(?P<name>.+)\",(?P<major>\d+(\.\d+)?),(?P<flattening>\d{3}\.\d+),') - - # For pulling out the units on platforms w/o GDAL installed. - # TODO: Figure out how to pull out angular units of projected coordinate system and - # fix for LOCAL_CS types. GDAL should be highly recommended for performing - # distance queries. - units_regex = re.compile(r'.+UNIT ?\["(?P<unit_name>[\w \'\(\)]+)", ?(?P<unit>[\d\.]+)(,AUTHORITY\["(?P<unit_auth_name>[\w \'\(\)]+)","(?P<unit_auth_val>\d+)"\])?\]([\w ]+)?(,AUTHORITY\["(?P<auth_name>[\w \'\(\)]+)","(?P<auth_val>\d+)"\])?\]$') - - @property - def srs(self): - """ - Returns a GDAL SpatialReference object, if GDAL is installed. - """ - if gdal.HAS_GDAL: - # TODO: Is caching really necessary here? Is complexity worth it? - if hasattr(self, '_srs'): - # Returning a clone of the cached SpatialReference object. - return self._srs.clone() - else: - # Attempting to cache a SpatialReference object. - - # Trying to get from WKT first. - try: - self._srs = gdal.SpatialReference(self.wkt) - return self.srs - except Exception as msg: - pass - - try: - self._srs = gdal.SpatialReference(self.proj4text) - return self.srs - except Exception as msg: - pass - - raise Exception('Could not get OSR SpatialReference from WKT: %s\nError:\n%s' % (self.wkt, msg)) - else: - raise Exception('GDAL is not installed.') - - @property - def ellipsoid(self): - """ - Returns a tuple of the ellipsoid parameters: - (semimajor axis, semiminor axis, and inverse flattening). - """ - if gdal.HAS_GDAL: - return self.srs.ellipsoid - else: - m = self.spheroid_regex.match(self.wkt) - if m: return (float(m.group('major')), float(m.group('flattening'))) - else: return None - - @property - def name(self): - "Returns the projection name." - return self.srs.name - - @property - def spheroid(self): - "Returns the spheroid name for this spatial reference." - return self.srs['spheroid'] - - @property - def datum(self): - "Returns the datum for this spatial reference." - return self.srs['datum'] - - @property - def projected(self): - "Is this Spatial Reference projected?" - if gdal.HAS_GDAL: - return self.srs.projected - else: - return self.wkt.startswith('PROJCS') - - @property - def local(self): - "Is this Spatial Reference local?" - if gdal.HAS_GDAL: - return self.srs.local - else: - return self.wkt.startswith('LOCAL_CS') - - @property - def geographic(self): - "Is this Spatial Reference geographic?" - if gdal.HAS_GDAL: - return self.srs.geographic - else: - return self.wkt.startswith('GEOGCS') - - @property - def linear_name(self): - "Returns the linear units name." - if gdal.HAS_GDAL: - return self.srs.linear_name - elif self.geographic: - return None - else: - m = self.units_regex.match(self.wkt) - return m.group('unit_name') - - @property - def linear_units(self): - "Returns the linear units." - if gdal.HAS_GDAL: - return self.srs.linear_units - elif self.geographic: - return None - else: - m = self.units_regex.match(self.wkt) - return m.group('unit') - - @property - def angular_name(self): - "Returns the name of the angular units." - if gdal.HAS_GDAL: - return self.srs.angular_name - elif self.projected: - return None - else: - m = self.units_regex.match(self.wkt) - return m.group('unit_name') - - @property - def angular_units(self): - "Returns the angular units." - if gdal.HAS_GDAL: - return self.srs.angular_units - elif self.projected: - return None - else: - m = self.units_regex.match(self.wkt) - return m.group('unit') - - @property - def units(self): - "Returns a tuple of the units and the name." - if self.projected or self.local: - return (self.linear_units, self.linear_name) - elif self.geographic: - return (self.angular_units, self.angular_name) - else: - return (None, None) - - @classmethod - def get_units(cls, wkt): - """ - Class method used by GeometryField on initialization to - retrive the units on the given WKT, without having to use - any of the database fields. - """ - if gdal.HAS_GDAL: - return gdal.SpatialReference(wkt).units - else: - m = cls.units_regex.match(wkt) - return m.group('unit'), m.group('unit_name') - - @classmethod - def get_spheroid(cls, wkt, string=True): - """ - Class method used by GeometryField on initialization to - retrieve the `SPHEROID[..]` parameters from the given WKT. - """ - if gdal.HAS_GDAL: - srs = gdal.SpatialReference(wkt) - sphere_params = srs.ellipsoid - sphere_name = srs['spheroid'] - else: - m = cls.spheroid_regex.match(wkt) - if m: - sphere_params = (float(m.group('major')), float(m.group('flattening'))) - sphere_name = m.group('name') - else: - return None - - if not string: - return sphere_name, sphere_params - else: - # `string` parameter used to place in format acceptable by PostGIS - if len(sphere_params) == 3: - radius, flattening = sphere_params[0], sphere_params[2] - else: - radius, flattening = sphere_params - return 'SPHEROID["%s",%s,%s]' % (sphere_name, radius, flattening) - - def __str__(self): - """ - Returns the string representation. If GDAL is installed, - it will be 'pretty' OGC WKT. - """ - try: - return six.text_type(self.srs) - except: - return six.text_type(self.wkt) |