app/django/contrib/gis/db/backend/postgis/adaptor.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

"""
 This object provides quoting for GEOS geometries into PostgreSQL/PostGIS.
"""

from django.contrib.gis.db.backend.postgis.query import GEOM_FROM_WKB
from psycopg2 import Binary
from psycopg2.extensions import ISQLQuote

class PostGISAdaptor(object):
    def __init__(self, geom):
        "Initializes on the geometry."
        # Getting the WKB (in string form, to allow easy pickling of
        # the adaptor) and the SRID from the geometry.
        self.wkb = str(geom.wkb)
        self.srid = geom.srid

    def __conform__(self, proto):
        # Does the given protocol conform to what Psycopg2 expects?
        if proto == ISQLQuote:
            return self
        else:
            raise Exception('Error implementing psycopg2 protocol. Is psycopg2 installed?')

    def __eq__(self, other):
        return (self.wkb == other.wkb) and (self.srid == other.srid)

    def __str__(self):
        return self.getquoted()

    def getquoted(self):
        "Returns a properly quoted string for use in PostgreSQL/PostGIS."
        # Want to use WKB, so wrap with psycopg2 Binary() to quote properly.
        return "%s(%s, %s)" % (GEOM_FROM_WKB, Binary(self.wkb), self.srid or -1)