[Chameleon] WFS client and HTTP GET/POST

[Paul Spencer]

Bart,

Assefa will be the best to answer this one, but my understanding is that 
mapserver will use XML encoded POST requests by default when acting as a 
WFS client.  There is supposed to be a metadata that can be set to 
control this behaviour at the layer level.

wfs_request_method : POST or GET

If we get around to implementing a WFS module that supports downloading 
capabilities then it is likely that setting this will be done 
explicitly.  However, for now, Chameleon will likely ignore this 
metadata and allow mapserver to use the default mode, which is POST.

The ExtractWFSData widget probably overrides this handling in some 
circumstances and just sends a GET request anyway.  We've never 
implemented a POST request in PHP code, a quick search reveals the 
following URL which provides two different ways of doing it:

http://www.alt-php-faq.org/local/55/

I'll get Bill to take a look at his code and see if there is a way to 
incorporate the possibility of either a post or get request and have it 
honour the metadata of the layer if set.

Cheers,

Paul

Bart van den Eijnden wrote:

> Hi list,
> 
> I would like to discuss an "issue" which has come accross my path when 
> trying to implement Chameleon functionality, and then especially the 
> ExtractWFSData widget, on a server different from Mapserver. I know this 
> is probably a long term issue, but anyway, always good to discuss these 
> things a.s.a.p in my opinion. Also, it is both a PHP Mapscript and a 
> Chameleon issue.
> 
> In the code of the ExtractWFSData widget it is assumed that the WFS 
> server supports the DCPTYPE HTTP GET request for GetFeature on the WFS 
> interface. For Mapserver this is true, but when I am using the ArcIMS 
> WFS Connector, it only supports DCPTYPE HTTP POST. Ofcourse those things 
> are advertized through the GetCapabilities interface, but for many 
> requests the GetCapabilities interface is skipped which is quite logical 
> taking into account performance.
> 
> Will the PHP/Mapscript code be enhanced in future, to support also an 
> advanced WFS Client which can use both GET and POST, and will Chameleon 
> use this functionality from PHP/Mapscript?
> 
> And will there be more wfs metadata tags then describing which DCPTYPE 
> (HTTP GET/POST) is supported for the various WFS interfaces, so the WFS 
> client will know what to do, or will the capabilities be parsed for this?
> 
> Best regards,
> Bart
> _______________________________________________
> Chameleon mailing list
> Chameleon@lists.maptools.org
> http://lists.maptools.org/mailman/listinfo/chameleon
> 

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|Paul Spencer                           spencer@dmsolutions.ca    |
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|Applications & Software Development                              |
|DM Solutions Group Inc                 http://www.dmsolutions.ca/|
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