[MapProxy] WMS-C as a source

[Jeff Konnen]

Hi Oliver!

You rock, thanks and it works like a charm!

Now I finally saw what was probably also the problem when I was using GDAL. Sometimes there are no tiles sent back because it is "nodata".
Neither GDAL nor MapProxy can handle this.

I saw in the doc of MP1.4.0a that there is a new parameter on_error.
I installed the new version and found that my case is not covered yet.

Actually, what I get is not an error, but an exception:

[2012-03-06 23:17:34,545] mapproxy.source.request - INFO - GET http://itchy.geoportal.lu/wmsc?service=WMS&request=GetMap&version=1.1.1&layers=ORTHOIMAGERY.ORTHOPHOTOS&styles=&srs=EPSG:310024802&format=image/jpeg&width=256&height=256&bbox=449536.00000000,5514240.00000000,450560.00000000,5515264.00000000 200 1.0 11
[2012-03-06 23:17:34,548] mapproxy.source.request - INFO - GET http://itchy.geoportal.lu/wmsc?service=WMS&request=GetMap&version=1.1.1&layers=ORTHOIMAGERY.ORTHOPHOTOS&styles=&srs=EPSG:310024802&format=image/jpeg&width=256&height=256&bbox=448512.00000000,5514240.00000000,449536.00000000,5515264.00000000 200 - 15
[2012-03-06 23:17:34,603] mapproxy.source.request - INFO - GET http://itchy.geoportal.lu/wmsc?service=WMS&request=GetMap&version=1.1.1&layers=ORTHOIMAGERY.ORTHOPHOTOS&styles=&srs=EPSG:310024802&format=image/jpeg&width=256&height=256&bbox=450560.00000000,5514240.00000000,451584.00000000,5515264.00000000 200 - 57
[2012-03-06 23:17:34,603] mapproxy.source.tile - WARNING - could not retrieve tile: response is not an image: (<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<!DOCTYPE ServiceExceptionReport [
    <!ELEMENT ServiceExceptionReport (ServiceException*)>
    <!ATTLIST ServiceExceptionReport version CDATA #FIXED "1.1.1">
    <!ELEMENT ServiceException (#PCDATA)>
    <!ATTLIST ServiceException code CDATA #IMPLIED>
    <!ATTLIST ServiceException locator CDATA #IMPLIED>
]>
<ServiceExceptionReport version="1.1.1">
        <ServiceException code="NoTileFound" locator="">
                <![CDATA[
                    Requested tile is not found (eventually because it is an empty "no-data" image).
                ]]>
        </ServiceException>
</ServiceExceptionReport>)
[2012-03-06 23:17:34,607] mapproxy.source.request - INFO - GET http://itchy.geoportal.lu/wmsc?service=WMS&request=GetMap&version=1.1.1&layers=ORTHOIMAGERY.ORTHOPHOTOS&styles=&srs=EPSG:310024802&format=image/jpeg&width=256&height=256&bbox=451584.00000000,5514240.00000000,452608.00000000,5515264.00000000 200 - 58
[2012-03-06 23:17:34,607] mapproxy.source.tile - WARNING - could not retrieve tile: response is not an image: (<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<!DOCTYPE ServiceExceptionReport [
    <!ELEMENT ServiceExceptionReport (ServiceException*)>
    <!ATTLIST ServiceExceptionReport version CDATA #FIXED "1.1.1">
    <!ELEMENT ServiceException (#PCDATA)>
    <!ATTLIST ServiceException code CDATA #IMPLIED>
    <!ATTLIST ServiceException locator CDATA #IMPLIED>
]>
<ServiceExceptionReport version="1.1.1">
        <ServiceException code="NoTileFound" locator="">
                <![CDATA[
                    Requested tile is not found (eventually because it is an empty "no-data" image).
                ]]>
        </ServiceException>
</ServiceExceptionReport>)
[info] 10.113.80.68 - - [06/Mar/2012 23:17:34] "GET /service?REQUEST=GetMap&SERVICE=WMS&VERSION=1.1.1&LAYERS=Ortho&STYLES=&FORMAT=image/jpeg&BGCOLOR=0xFFFFFF&TRANSPARENT=TRUE&SRS=EPSG:2169&BBOX=57813.307456103,60448.7767579583,66843.1407711681,66762.9213969255&WIDTH=1340&HEIGHT=937 HTTP/1.1" 200 -
[2012-03-06 23:17:34,660] mapproxy.source.request - INFO - GET http://itchy.geoportal.lu/wmsc?service=WMS&request=GetMap&version=1.1.1&layers=ORTHOIMAGERY.ORTHOPHOTOS&styles=&srs=EPSG:310024802&format=image/jpeg&width=256&height=256&bbox=452608.00000000,5514240.00000000,453632.00000000,5515264.00000000 200 - 56
[2012-03-06 23:17:34,661] mapproxy.source.tile - WARNING - could not retrieve tile: response is not an image: (<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<!DOCTYPE ServiceExceptionReport [
    <!ELEMENT ServiceExceptionReport (ServiceException*)>
    <!ATTLIST ServiceExceptionReport version CDATA #FIXED "1.1.1">
    <!ELEMENT ServiceException (#PCDATA)>
    <!ATTLIST ServiceException code CDATA #IMPLIED>
    <!ATTLIST ServiceException locator CDATA #IMPLIED>
]>
<ServiceExceptionReport version="1.1.1">
        <ServiceException code="NoTileFound" locator="">
                <![CDATA[
                    Requested tile is not found (eventually because it is an empty "no-data" image).
                ]]>
        </ServiceException>
</ServiceExceptionReport>)

So ideally in addition to on_error there would be an on_exception too ;-)

I tried forking the repository to write a patch but somehow I can't access bitbucked from behind my proxy..

Thanks again
Jeff