app/django/contrib/gis/db/backend/postgis/models.py
author Sverre Rabbelier <srabbelier@gmail.com>
Fri, 23 Jan 2009 21:20:33 +0000
changeset 935 09f47e08f805
parent 323 ff1a9aa48cfd
permissions -rw-r--r--
Adust the as_table tag to render a pick link if appropriate The templates are adjusted to pass on a 'reference' value, which is the url_name of the view from which the entity should be picked. The as_table (and related) function(s) construct and then pass on this argument and enable takes_contex so that we have access to the context of the enclosing template. We only extract ReferenceProperties that end with '_link_id' since that is how all RP's are currently named. It is not possible to create a field with the same name as the RP, as GAE will try to interpret it's contents as the key of an entity before even calling any function we can override. Patch by: Sverre Rabbelier

"""
 The GeometryColumns and SpatialRefSys models for the PostGIS backend.
"""
from django.db import models
from django.contrib.gis.models import SpatialRefSysMixin

# Checking for the presence of GDAL (needed for the SpatialReference object)
from django.contrib.gis.gdal import HAS_GDAL
if HAS_GDAL:
    from django.contrib.gis.gdal import SpatialReference

class GeometryColumns(models.Model):
    """
    The 'geometry_columns' table from the PostGIS. See the PostGIS
    documentation at Ch. 4.2.2.
    """
    f_table_catalog = models.CharField(max_length=256)
    f_table_schema = models.CharField(max_length=256)
    f_table_name = models.CharField(max_length=256)
    f_geometry_column = models.CharField(max_length=256)
    coord_dimension = models.IntegerField()
    srid = models.IntegerField(primary_key=True)
    type = models.CharField(max_length=30)

    class Meta:
        db_table = 'geometry_columns'

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

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

    def __unicode__(self):
        return "%s.%s - %dD %s field (SRID: %d)" % \
               (self.f_table_name, self.f_geometry_column,
                self.coord_dimension, self.type, self.srid)

class SpatialRefSys(models.Model, SpatialRefSysMixin):
    """
    The 'spatial_ref_sys' table from PostGIS. See the PostGIS
    documentaiton at Ch. 4.2.1.
    """
    srid = models.IntegerField(primary_key=True)
    auth_name = models.CharField(max_length=256)
    auth_srid = models.IntegerField()
    srtext = models.CharField(max_length=2048)
    proj4text = models.CharField(max_length=2048)

    class Meta:
        db_table = 'spatial_ref_sys'

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

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