Web Map Context interoperability problems

[Daniel Morissette]

Hi Bart,

Could you please file a bug and Julien will have a look and provide more 
precise answers?

Quick comments about the issues that you raised:

About the EPSG code not being recognized, we've used 4326 before and I 
don't thing the pszValue+5 implies that the EPSG code needs to be 5 
digits, I think it's there to skip the "EPSG:" prefix. It has to be 
something else, we'll need to check further with this

About #1: you're right that this is missing

About #2: MapServer 4.9 should spit out "OGC:WMS" for v1.1.0 contexts, 
and "WMS" for 1.0.0 ... I didn't double-check the specs, but I think 
this is the correct behavior.

Daniel


Bart van den Eijnden wrote:
> Hi list,
> 
> I am trying to use a WMC document generated by Ionic in Mapserver, but
> cannot get it to work (no layers in map object). The Ionic context
> validates in Oxygen.
> 
> First problem, Ionic does not use a XML header for the context, so
> Mapserver comes back with:
> 
> PHP Warning:  [MapServer Error]: msLoadMapContext(): Invalid XML file
> (/data/geoservices/apps/geoservices/htdocs/ionic.cml)
>  in /data/geoservices/apps/geoservices/htdocs/wmc_ionic.php on line 5
> 
> So I added the XML header by hand. Then the following problem occurs:
> 
> PHP Warning:  [MapServer Error]: msLoadMapContext(): Unable to set units
> for projection ''
> 
> Could it be that the Mapserver code assumes a 5 letter SRS EPSG code? If I
> use e.g. 28992 it runs fine.
> 
> sprintf(pszProj, "init=epsg:%s", pszValue+5);
> 
> I have seen a few other potential problems in the Mapserver code:
> 
> 1) the parsing code for queryable etc. assumes to get a 0 or 1, whereas
> true or false are also valid values for xs:boolean
> 
> 2) when outputting a WMC, Mapserver uses WMS for the value of the service
> attribute of Server, whereas the OGC example (on schemas.opengis.net) as
> well as Ionic use OGC:WMS
> 
> <Server service="OGC:WMS"
> 
> I have attached the context if somebody is interested to try this out.
> 
> Best regards,
> Bart
> 
> 
> ------------------------------------------------------------------------
> 
>   <ViewContext xmlns:xlink="http://www.w3.org/1999/xlink" xsi:schemaLocation="http://www.opengis.net/context http://schemas.opengis.net/context/1.0.0/context.xsd" xmlns="http://www.opengis.net/context" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" id="none" version="1.0.0">
>     <General>
>       <Window width="600" height="300"></Window>
> 
>       <BoundingBox SRS="EPSG:4326" miny="28.200000000000017" maxy="58.80000000000001" maxx="41.39999999999999" minx="-19.799999999999994"></BoundingBox>
> 
>       <Title>World view</Title>
> 
>       <Abstract>Example Context</Abstract>
> 
>     </General>
> 
>     <LayerList>
>       <Layer hidden="0" queryable="false">
>         <Server service="OGC:WMS" title="WORLD" version="1.1.1">
>           <OnlineResource xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://webservices.ionicsoft.com/worldData/map/WORLD" xlink:type="simple"></OnlineResource>
> 
>         </Server>
> 
>         <Name>WORLD</Name>
> 
>         <Title>WORLD</Title>
> 
>         <Abstract></Abstract>
> 
>         <StyleList>
>           <Style current="1">
>             <Name>default</Name>
> 
>             <Title>default</Title>
> 
>           </Style>
> 
>         </StyleList>
> 
>       </Layer>
> 
>     </LayerList>
> 
>   </ViewContext>
>   


-- 
Daniel Morissette
http://www.mapgears.com/