app/django/contrib/gis/forms/fields.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

from django import forms
from django.contrib.gis.db.backend import SpatialBackend
from django.utils.translation import ugettext_lazy as _

class GeometryField(forms.Field):
    """
    This is the basic form field for a Geometry.  Any textual input that is
    accepted by SpatialBackend.Geometry is accepted by this form.  By default, 
    this is GEOSGeometry, which accepts WKT, HEXEWKB, WKB, and GeoJSON.
    """
    widget = forms.Textarea

    default_error_messages = {
        'no_geom' : _(u'No geometry value provided.'),
        'invalid_geom' : _(u'Invalid geometry value.'),
        'invalid_geom_type' : _(u'Invalid geometry type.'),
    }

    def __init__(self, **kwargs):
        self.null = kwargs.pop('null')
        self.geom_type = kwargs.pop('geom_type')
        super(GeometryField, self).__init__(**kwargs)

    def clean(self, value):
        """
        Validates that the input value can be converted to a Geometry
        object (which is returned).  A ValidationError is raised if
        the value cannot be instantiated as a Geometry.
        """
        if not value:
            if self.null:
                # The geometry column allows NULL, return None.
                return None
            else:
                raise forms.ValidationError(self.error_messages['no_geom'])
     
        try:
            # Trying to create a Geometry object from the form value.
            geom = SpatialBackend.Geometry(value)
        except:
            raise forms.ValidationError(self.error_messages['invalid_geom'])
  
        # Ensuring that the geometry is of the correct type (indicated
        # using the OGC string label).
        if str(geom.geom_type).upper() != self.geom_type and not self.geom_type == 'GEOMETRY':
            raise forms.ValidationError(self.error_messages['invalid_geom_type'])

        return geom