ArcSDE fails with WFS server

[sean.geoghegan@…]

When using the WFS server with an ArcSDE layer, no features are returned,
however the same layer with the WMS server returns an appropriate image
containing the features from the SDE layer.  No error messages appear in the WFS
response either, just an empty feature collection.

Using this version of MapServer:
MapServer version 3.7 (development) OUTPUT=PNG OUTPUT=JPEG OUTPUT=WBMP SUPPORTS=
PROJ SUPPORTS=TTF SUPPORTS=WMS_SERVER SUPPORTS=WFS_SERVER SUPPORTS=GD2_RGB INPUT
=EPPL7 INPUT=SDE INPUT=OGR INPUT=GDAL INPUT=SHAPEFILE

If any more information is required or there is a method for getting some more
informative error messages, please let me know.  I will also be willing to
assist in tracking down the problem or helping in any way I can.

Thanks
Sean Geoghegan

[dmorissette]

Steve, would you be able to help in troubleshooting this since I believe you do 
have access to SDE?  I suspect the problem would be that the WFS implementation 
assumes that the maplayer.c functions can be called in some order, but the SDE 
driver (and perhaps others) is not written to accept calls in the order that the 
WFS interface makes them.

[sdlime]

Ok, I believe I've found this one. It has to do with the connection pooling we 
added early on in 4.0 development. SDE streams are now shared amongst layers or 
even within the same layer. You see the problem when doing queries since they 
involve 2 interactions with SDE. One for the intial query which builds a list 
of matching records, and a second interaction to actually get the data. The 
pooling definitely helps. However, after the initial query (or even when doing 
an index query) the SDE stream can be left in limbo. So, I moved a bit of code 
that resets the stream to a slightly different spot and that helps. I've only 
tested with CGI queries but since WFS is really just a wrapper for MapServer 
queries I believe it will fix this bug too. I'll leave it open until I can get 
confirmation from someone.

Steve

[dmorissette]

Sean, I'll mark this fixed in light of what Steve wrote.  Please reopen if the 
same still happens with the latest 4.0 code.

[sdlime]

There is still one outstanding issue that I will fix sometime today. Fine to
consider closed.

Steve