| """ |
| This module contains the spatial lookup types, and the `get_geo_where_clause` |
| routine for Oracle Spatial. |
| |
| Please note that WKT support is broken on the XE version, and thus |
| this backend will not work on such platforms. Specifically, XE lacks |
| support for an internal JVM, and Java libraries are required to use |
| the WKT constructors. |
| """ |
| import re |
| from decimal import Decimal |
| from django.db import connection |
| from django.contrib.gis.db.backend.util import SpatialFunction |
| from django.contrib.gis.measure import Distance |
| qn = connection.ops.quote_name |
| |
| # The GML, distance, transform, and union procedures. |
| AREA = 'SDO_GEOM.SDO_AREA' |
| ASGML = 'SDO_UTIL.TO_GMLGEOMETRY' |
| CENTROID = 'SDO_GEOM.SDO_CENTROID' |
| DIFFERENCE = 'SDO_GEOM.SDO_DIFFERENCE' |
| DISTANCE = 'SDO_GEOM.SDO_DISTANCE' |
| EXTENT = 'SDO_AGGR_MBR' |
| INTERSECTION = 'SDO_GEOM.SDO_INTERSECTION' |
| LENGTH = 'SDO_GEOM.SDO_LENGTH' |
| NUM_GEOM = 'SDO_UTIL.GETNUMELEM' |
| NUM_POINTS = 'SDO_UTIL.GETNUMVERTICES' |
| POINT_ON_SURFACE = 'SDO_GEOM.SDO_POINTONSURFACE' |
| SYM_DIFFERENCE = 'SDO_GEOM.SDO_XOR' |
| TRANSFORM = 'SDO_CS.TRANSFORM' |
| UNION = 'SDO_GEOM.SDO_UNION' |
| UNIONAGG = 'SDO_AGGR_UNION' |
| |
| # We want to get SDO Geometries as WKT because it is much easier to |
| # instantiate GEOS proxies from WKT than SDO_GEOMETRY(...) strings. |
| # However, this adversely affects performance (i.e., Java is called |
| # to convert to WKT on every query). If someone wishes to write a |
| # SDO_GEOMETRY(...) parser in Python, let me know =) |
| GEOM_SELECT = 'SDO_UTIL.TO_WKTGEOMETRY(%s)' |
| |
| #### Classes used in constructing Oracle spatial SQL #### |
| class SDOOperation(SpatialFunction): |
| "Base class for SDO* Oracle operations." |
| def __init__(self, func, **kwargs): |
| kwargs.setdefault('operator', '=') |
| kwargs.setdefault('result', 'TRUE') |
| kwargs.setdefault('end_subst', ") %s '%s'") |
| super(SDOOperation, self).__init__(func, **kwargs) |
| |
| class SDODistance(SpatialFunction): |
| "Class for Distance queries." |
| def __init__(self, op, tolerance=0.05): |
| super(SDODistance, self).__init__(DISTANCE, end_subst=', %s) %%s %%s' % tolerance, |
| operator=op, result='%%s') |
| |
| class SDOGeomRelate(SpatialFunction): |
| "Class for using SDO_GEOM.RELATE." |
| def __init__(self, mask, tolerance=0.05): |
| # SDO_GEOM.RELATE(...) has a peculiar argument order: column, mask, geom, tolerance. |
| # Moreover, the runction result is the mask (e.g., 'DISJOINT' instead of 'TRUE'). |
| end_subst = "%s%s) %s '%s'" % (', %%s, ', tolerance, '=', mask) |
| beg_subst = "%%s(%%s, '%s'" % mask |
| super(SDOGeomRelate, self).__init__('SDO_GEOM.RELATE', beg_subst=beg_subst, end_subst=end_subst) |
| |
| class SDORelate(SpatialFunction): |
| "Class for using SDO_RELATE." |
| masks = 'TOUCH|OVERLAPBDYDISJOINT|OVERLAPBDYINTERSECT|EQUAL|INSIDE|COVEREDBY|CONTAINS|COVERS|ANYINTERACT|ON' |
| mask_regex = re.compile(r'^(%s)(\+(%s))*$' % (masks, masks), re.I) |
| def __init__(self, mask): |
| func = 'SDO_RELATE' |
| if not self.mask_regex.match(mask): |
| raise ValueError('Invalid %s mask: "%s"' % (func, mask)) |
| super(SDORelate, self).__init__(func, end_subst=", 'mask=%s') = 'TRUE'" % mask) |
| |
| #### Lookup type mapping dictionaries of Oracle spatial operations #### |
| |
| # Valid distance types and substitutions |
| dtypes = (Decimal, Distance, float, int, long) |
| DISTANCE_FUNCTIONS = { |
| 'distance_gt' : (SDODistance('>'), dtypes), |
| 'distance_gte' : (SDODistance('>='), dtypes), |
| 'distance_lt' : (SDODistance('<'), dtypes), |
| 'distance_lte' : (SDODistance('<='), dtypes), |
| 'dwithin' : (SDOOperation('SDO_WITHIN_DISTANCE', |
| beg_subst="%s(%s, %%s, 'distance=%%s'"), dtypes), |
| } |
| |
| ORACLE_GEOMETRY_FUNCTIONS = { |
| 'contains' : SDOOperation('SDO_CONTAINS'), |
| 'coveredby' : SDOOperation('SDO_COVEREDBY'), |
| 'covers' : SDOOperation('SDO_COVERS'), |
| 'disjoint' : SDOGeomRelate('DISJOINT'), |
| 'intersects' : SDOOperation('SDO_OVERLAPBDYINTERSECT'), # TODO: Is this really the same as ST_Intersects()? |
| 'equals' : SDOOperation('SDO_EQUAL'), |
| 'exact' : SDOOperation('SDO_EQUAL'), |
| 'overlaps' : SDOOperation('SDO_OVERLAPS'), |
| 'same_as' : SDOOperation('SDO_EQUAL'), |
| 'relate' : (SDORelate, basestring), # Oracle uses a different syntax, e.g., 'mask=inside+touch' |
| 'touches' : SDOOperation('SDO_TOUCH'), |
| 'within' : SDOOperation('SDO_INSIDE'), |
| } |
| ORACLE_GEOMETRY_FUNCTIONS.update(DISTANCE_FUNCTIONS) |
| |
| # This lookup type does not require a mapping. |
| MISC_TERMS = ['isnull'] |
| |
| # Acceptable lookup types for Oracle spatial. |
| ORACLE_SPATIAL_TERMS = ORACLE_GEOMETRY_FUNCTIONS.keys() |
| ORACLE_SPATIAL_TERMS += MISC_TERMS |
| ORACLE_SPATIAL_TERMS = dict((term, None) for term in ORACLE_SPATIAL_TERMS) # Making dictionary for fast lookups |
| |
| #### The `get_geo_where_clause` function for Oracle #### |
| def get_geo_where_clause(table_alias, name, lookup_type, geo_annot): |
| "Returns the SQL WHERE clause for use in Oracle spatial SQL construction." |
| # Getting the quoted table name as `geo_col`. |
| geo_col = '%s.%s' % (qn(table_alias), qn(name)) |
| |
| # See if a Oracle Geometry function matches the lookup type next |
| lookup_info = ORACLE_GEOMETRY_FUNCTIONS.get(lookup_type, False) |
| if lookup_info: |
| # Lookup types that are tuples take tuple arguments, e.g., 'relate' and |
| # 'dwithin' lookup types. |
| if isinstance(lookup_info, tuple): |
| # First element of tuple is lookup type, second element is the type |
| # of the expected argument (e.g., str, float) |
| sdo_op, arg_type = lookup_info |
| |
| # Ensuring that a tuple _value_ was passed in from the user |
| if not isinstance(geo_annot.value, tuple): |
| raise TypeError('Tuple required for `%s` lookup type.' % lookup_type) |
| if len(geo_annot.value) != 2: |
| raise ValueError('2-element tuple required for %s lookup type.' % lookup_type) |
| |
| # Ensuring the argument type matches what we expect. |
| if not isinstance(geo_annot.value[1], arg_type): |
| raise TypeError('Argument type should be %s, got %s instead.' % (arg_type, type(geo_annot.value[1]))) |
| |
| if lookup_type == 'relate': |
| # The SDORelate class handles construction for these queries, |
| # and verifies the mask argument. |
| return sdo_op(geo_annot.value[1]).as_sql(geo_col) |
| else: |
| # Otherwise, just call the `as_sql` method on the SDOOperation instance. |
| return sdo_op.as_sql(geo_col) |
| else: |
| # Lookup info is a SDOOperation instance, whose `as_sql` method returns |
| # the SQL necessary for the geometry function call. For example: |
| # SDO_CONTAINS("geoapp_country"."poly", SDO_GEOMTRY('POINT(5 23)', 4326)) = 'TRUE' |
| return lookup_info.as_sql(geo_col) |
| elif lookup_type == 'isnull': |
| # Handling 'isnull' lookup type |
| return "%s IS %sNULL" % (geo_col, (not geo_annot.value and 'NOT ' or '')) |
| |
| raise TypeError("Got invalid lookup_type: %s" % repr(lookup_type)) |