app/django/contrib/gis/db/backend/oracle/models.py
author Sverre Rabbelier <srabbelier@gmail.com>
Sat, 06 Dec 2008 14:23:53 +0000
changeset 679 77a286ff6667
parent 323 ff1a9aa48cfd
permissions -rw-r--r--
Introduce dynamic scope_path regexps Instead of relying on scope_path's being "one slash deep", we should instead allow for either: 1. scope_paths that have a pre-defined depth 2. scope_paths that can be arbitrarily deep We achieve 1 by setting an entities scope_logic to another logic module. We then recursively call getScopeDepth until we get to the topmost entity (that is, an unscoped entity). A little different is the solution to 2, since some entities can have an arbitrarily deep scope (such as Documents), we need to have some way of signaling this to getScopePattern. A clean solution is to return None, rather than a number. If None is returned, the SCOPE_PATH_ARG_PATTERN is returned as regexp instead, which will match an arbitrarily deeply nested scope. The solution for 2 requires that we return None somewhere in the scope_logic chain, the most straight forward method to do so is to override getScopeDepth anywhere such a scope is needed and make it return None. A more elegant solution however, is to set the scope_logic to that module in all entities that require it. Patch by: Sverre Rabbelier

"""
 The GeometryColumns and SpatialRefSys models for the Oracle spatial
 backend.

 It should be noted that Oracle Spatial does not have database tables
 named according to the OGC standard, so the closest analogs are used.
 For example, the `USER_SDO_GEOM_METADATA` is used for the GeometryColumns
 model and the `SDO_COORD_REF_SYS` is used for the SpatialRefSys model.
"""
from django.db import models
from django.contrib.gis.models import SpatialRefSysMixin

class GeometryColumns(models.Model):
    "Maps to the Oracle USER_SDO_GEOM_METADATA table."
    table_name = models.CharField(max_length=32)
    column_name = models.CharField(max_length=1024)
    srid = models.IntegerField(primary_key=True)
    # TODO: Add support for `diminfo` column (type MDSYS.SDO_DIM_ARRAY).
    class Meta:
        db_table = 'USER_SDO_GEOM_METADATA'

    @classmethod
    def table_name_col(cls):
        """
        Returns the name of the metadata column used to store the 
        the feature table name.
        """
        return 'table_name'

    @classmethod
    def geom_col_name(cls):
        """
        Returns the name of the metadata column used to store the 
        the feature geometry column.
        """
        return 'column_name'

    def __unicode__(self):
        return '%s - %s (SRID: %s)' % (self.table_name, self.column_name, self.srid)

class SpatialRefSys(models.Model, SpatialRefSysMixin):
    "Maps to the Oracle MDSYS.CS_SRS table."
    cs_name = models.CharField(max_length=68)
    srid = models.IntegerField(primary_key=True)
    auth_srid = models.IntegerField()
    auth_name = models.CharField(max_length=256)
    wktext = models.CharField(max_length=2046)
    #cs_bounds = models.GeometryField()

    class Meta:
        # TODO: Figure out way to have this be MDSYS.CS_SRS without
        #  having django's quoting mess up the SQL.
        db_table = 'CS_SRS'

    @property
    def wkt(self):
        return self.wktext

    @classmethod
    def wkt_col(cls):
        return 'wktext'