[Bug]: (fixed) Filter exports won't work (py-qgis-server) if service capabilities > WMS options not ticked

[timbo-barnes]

What is the bug? (in English)

We've recently changed our Lizmap install to use py_qgis_server (previously, QGIS server). In trying to find out why exports weren't working from a filter, I discovered an undocumented requirement for the services capabilities
Under Project Properties > QGIS Server > WMS
If 'Add geometry to feature response' is unticked, exports will not work.

Steps to reproduce the issue

Enable a filter for a layer (including WFS prerequisites etc)
In Project Properties > QGIS Server > WMS
If 'Add geometry to feature response' is unticked, exports will not work.

Versions, safeguards, check summary etc

Versions :

• Lizmap Web Client : 3.9.3 - commit 32bad13 32bad131d
• Lizmap plugin : 4.5.10
• QGIS Desktop : 3.44.7
• QGIS Server : 3.44.7
• Py-QGIS-Server : 1.9.6
• QGIS Server plugin atlasprint : 3.4.3
• QGIS Server plugin lizmap_server : 2.14.1
• QGIS Server plugin wfsOutputExtension : 1.8.3

List of Lizmap Web Client modules :

* Version Lizmap Web Client 3.8 needed

List of safeguards :

* Mode : normal
* Allow parent folder : no
* Prevent other drive : yes
* Prevent PG service : no
* Prevent PG Auth DB : yes
* Force PG user&pass : yes
* Prevent ECW : yes

Check Lizmap plugin

• I have done the step just before in the Lizmap QGIS desktop plugin before opening this ticket. Otherwise, my ticket is not considered valid and might get closed.

Operating system

Ubuntu Linux 24.04.4

Browsers

Chrome

Browsers version

148.0.7778.97

Relevant log output