librelist archives

Re: [geonode] Native SRS in data view is always EPSG:32044

From:

David Winslow

Date:

2011-08-22 @ 16:23

Please :)

The worldmap way probably performs better -- but it increases the amount of
data duplicated between GeoServer and the GeoNode Django app which has been
identified by most of the GeoNode developers as a bad thing.  There are some
ideas floating around about how to have GeoNode get this sort of information
with just a database access while avoiding the duplication - but they are
some ways off.

--
David Winslow
OpenGeo - http://opengeo.org/

On Mon, Aug 22, 2011 at 12:15 PM, luca.casagrande@gmail.com <
luca.casagrande@gmail.com> wrote:

> Thanks David for this clarification..I tested and now the EPSG is the
> correct one.
> I think that this approach it's the better solution.
> Should I submit a pull request?
>
> Ciao
> L.
>
> 2011/8/22 David Winslow <dwinslow@opengeo.org>:
> > In mainline GeoNode we use OWSLib to get this information.  Apparently
> the
> > coder who added this bit didn't realize that in the WMS capabilities
> > document the SRS's listed are ones that the server can  use for display,
> not
> > the native projection for the format.  Looking into it, I don't think we
> can
> > use WMS for this at all - AFAICT there is no standard way to identify the
> > native projection of a layer via WMS.  (Maybe using the CRS associated
> with
> > the BoundingBox for the layer would do it.)
> >
> > Fortunately we have access to the GeoServer REST API so we can just use
> {%
> > layer.resource.projection %} instead.  Indeed, that is what the Worldmap
> > guys are copying into the Django database in the snippet you posted.
> Since
> > we can fix this problem without modifying the database schema I would
> like
> > to, modifying the schema would complicate the upgrade process a bit and
> our
> > documentation is lacking already.
> >
> > --
> > David Winslow
> > OpenGeo - http://opengeo.org/
> >
> > On Mon, Aug 22, 2011 at 3:26 AM, luca.casagrande@gmail.com
> > <luca.casagrande@gmail.com> wrote:
> >>
> >> Hi Stefano,
> >>
> >> 2011/8/22 Stefano Menegon <ste.menegon@gmail.com>:
> >> > Hi Luca,
> >> >
> >> >
> >> >> for every data, the Native SRS shown is always 32044. Looking at the
> >> >> code it seems that the problem is in:
> >> >> {% if layer.metadata.crsOptions %}<p> <strong>{% trans "Native SRS"
> >> >> %}:</strong> {{ layer.metadata.crsOptions.0|default:_("No SRS
> >> >> specified.") }} </p>{% endif %}
> >> >>
> >> >> layer.metadata.crsOptions is a big list of CRS and
> >> >> layer.metadata.crsOptions.0 gives EPSG:32044.
> >> >>
> >> >> Any idea?
> >> >> Thx
> >> >
> >> > I investigated it a few weeks ago.
> >> > The param "layer.metadata.crsOptions" is the list of all the CRS
> >> > supported by geoserver wms.
> >> > So, it always displays the first of these CRS, not realy the native
> SRS.
> >> >
> >> > You can configure the "Limited SRS list" option (Geoserver - Services
> >> > -  WMS) in order to change the layer.metadata.crsOptions value,
> >> > however, I do not know how to get the native SRS value.
> >> >
> >> > //stefano menegon
> >> >
> >>
> >> I double checked with World Map and the Layer class has got an srs
> >> attribute:
> >>
> >>
> 
https://github.com/cga-harvard/cga-worldmap/blob/master/src/GeoNodePy/geonode/maps/models.py#L842
> >>
> >> If I am not wrong the value is set here:
> >>
> >>
> 
https://github.com/cga-harvard/cga-worldmap/blob/master/src/GeoNodePy/geonode/maps/models.py#L1283
> >>
> >> Then in the template you have got layer.srs
> >>
> >> Ciao
> >> Luca
> >>
> >>
> >> --
> >> Luca Casagrande
> >> twitter: lucacasagrande
> >
> >
>
>
>
> --
> Luca Casagrande
> twitter: lucacasagrande
>