Bug WMS QGIS GetFeatureInfo returning entity

[ThomasG77]

What is the bug or the crash?

Considering QGIS attached project (see how to reproduced part for file),

I got a parsing issue from returned content after GetFeatureInfo query using "Identify feature"

For layer "INSEE.FILOSOFI.POPULATION" named in layer tree "Densité de population", WMS URL is https://wxs.ign.fr/economie/geoportail/r/wms?VERSION=1.3.0

When you try to query as entity, it returns error like in attached image. Using the request debugger, I see QGIS does a request using INFO_FORMAT=application/json instead of one requesting GML (not available in capabilities) so, the returned entity should not be parsed as GML but as GeoJSON/JSON, hence thee issue. Below a sample of the GetFeatureInfo query in the network debugger https://wxs.ign.fr/economie/geoportail/r/wms?SERVICE=WMS&VERSION=1.3.0&REQUEST=GetFeatureInfo&BBOX=880288.54028120101429522,6862834.76942052692174911,889264.71626451192423701,6871157.00023245997726917&CRS=EPSG:2154&WIDTH=1153&HEIGHT=1069&LAYERS=INSEE.FILOSOFI.POPULATION&STYLES=&FORMAT=image/jpeg&QUERY_LAYERS=INSEE.FILOSOFI.POPULATION&INFO_FORMAT=application/json&I=833&J=382&FEATURE_COUNT=10

Excerpt of the GetFeatureInfo part in WMS capabilities (curl -s "https://wxs.ign.fr/economie/geoportail/r/wms?SERVICE=WMS&VERSION=1.3.0&REQUEST=GetCapabilities" |xmllint --format -)

      <GetFeatureInfo>
        <Format>text/plain</Format>
        <Format>text/html</Format>
        <Format>text/xml</Format>
        <Format>application/xml</Format>
        <Format>application/json</Format>
        <DCPType>
          <HTTP>
            <Get>
              <OnlineResource xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="https://wxs.ign.fr/economie/geoportail/r/wms?" xlink:type="simple"/>
            </Get>
          </HTTP>
        </DCPType>
      </GetFeatureInfo>

Steps to reproduce the issue

• open the attached project debug-qgis-ogc-wms.qgz.zip,
• click on a feature choosing "entity" in the panel associated with "Identify feature"
• get the following error message (screenshot)

Versions

QGIS version	3.22.11-Białowieża	QGIS code branch	Release 3.22
Qt version	5.15.6
Python version	3.9.13
GDAL/OGR version	3.5.2
PROJ version	9.0.1
EPSG Registry database version	v10.064 (2022-05-19)
GEOS version	3.11.0-CAPI-1.17.0
Compiled against SQLite	3.39.3	Running against SQLite	3.40.0
PDAL version	2.4.3
PostgreSQL client version	14.5
SpatiaLite version	5.0.1
QWT version	6.2.0
QScintilla2 version	2.13.3
OS version	Ubuntu 18.04.6 LTS
Active Python plugins
densityanalysis	2022.9.14
DataPlotly	3.9.2
contour	2.0.10
sagaprovider	2.12.99
db_manager	0.1.20
processing	2.12.99
MetaSearch	0.3.5
grassprovider	2.12.99

Supported QGIS version

• I'm running a supported QGIS version according to the roadmap.

New profile

• I tried with a new QGIS profile

Additional context

Not running a supported version because using conda that only comes with 3.22.11 at the moment.

[pathmapper]

Same error message with QGIS 3.29.0-Master (2a0fc59).

[elpaso]

This might well be a QGIS bug because QGIS should not request an info format which is not in getcapabilities, but shouldn't the server also respond with an exception if a request for an unsupported info format is made?

[pathmapper]

QGIS should not request an info format which is not in getcapabilities

Looks like this it not the case, the request includes INFO_FORMAT=application/json which is included in GetCapabilities.

The issue is here, that QGIS tries to parse the JSON response as GML.