Missing Update operation for WFS layers without geometry

[gisuser0]

What is the bug or the crash?

Only Query, Insert and Delete are allowed for WFS layers without geometry. The Update operation is not available.

Steps to reproduce the issue

1. load any table without geometry into a QGIS project and enable all the WFS capabilities: Insert, Update and Delete (Project -> Properties -> QGIS Server -> WFS/OAPIF tab)
2. publish the project with QGIS-Server
3. Query, Insert and Delete are listed in the Operations of the WFS getCapabilities but Update is missing
4. open the layer with a WFS client (e.g. QGIS Desktop) and try to edit it: you can query, create and delete features but you can't update them

Versions

3.34.14 LTR (Windows and Linux)
3.40.2 (Windows and Linux)

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

Looking into the code it seems like the Update operation always requires the change geometry capability (Qgis::VectorProviderCapability::ChangeGeometries)

[elpaso]

I cannot reproduce and I think I need more details about the aspatial layer you are testing with (can you attach a small/minimal sample?)

[gisuser0]

Steps to reproduce the issue:

1. Create a PostgreSQL/PostGIS database
   CREATE DATABASE testwfs;

2. Connect to the database and create one table with geometries and one table without geometries:
   CREATE EXTENSION IF NOT EXISTS postgis;
CREATE TABLE with_geom (id serial, geom geography(POINT,4326), description character varying, CONSTRAINT with_geom_pkey PRIMARY KEY (id));
CREATE TABLE without_geom (id serial, description character varying, CONSTRAINT without_geom_pkey PRIMARY KEY (id));

3. Create a feature with geometry and a feature without geometry:
   INSERT INTO with_geom (geom, description) VALUES('SRID=4326;POINT(0 0)', 'With geometry');
INSERT INTO without_geom (description) VALUES('Without geometry');

4. Open an empty QGIS project, connect to the database and import the two tables (check "Also list tables with no geometry" in the connection properties in order to view also the without_geom table)

5. Enable all the WFS capabilities for both the layers (Project -> Properties -> QGIS Server -> WFS/OAPIF tab: check Published, Update, Insert and Delete)

6. Publish the project with QGIS-Server

7. Call the WFS getCapabilities. The with_geom layer has the Update operation while the without_geom layer doesn't have the Update operation

with_geom

<Name>with_geom</Name>
<Title>with_geom</Title>
<DefaultSRS>EPSG:4326</DefaultSRS>
<OtherSRS>EPSG:3857</OtherSRS>
<Operations>
<Operation>Query</Operation>
<Operation>Insert</Operation>
<Operation>Update</Operation>
<Operation>Delete</Operation>
</Operations>

without_geom

<Name>without_geom</Name>
<Title>without_geom</Title>
<DefaultSRS/>
<OtherSRS>EPSG:4326</OtherSRS>
<OtherSRS>EPSG:3857</OtherSRS>
<Operations>
<Operation>Query</Operation>
<Operation>Insert</Operation>
<Operation>Delete</Operation>
</Operations>

8. connect to the WFS service with QGIS Desktop and try to change the description field in both the layers: the field in the with_geom table is editable while the field in the without_geom is not editable

[elpaso]

@gisuser0 for the record, the fact that you were using postgres was the missing information to be able to reproduce the issue.

[gisuser0]

Thx for the fix

[gisuser0]

It seems like the missing check isSpatial() also for the wfs transaction block the update.

qgswfstransaction.cpp

Qgis::VectorProviderCapabilities cap = provider->capabilities();
      if ( !( cap & Qgis::VectorProviderCapability::ChangeAttributeValues ) || !( cap & Qgis::VectorProviderCapability::ChangeGeometries ) )
      {
        action.error = true;
        action.errorMsg = QStringLiteral( "No capabilities to do WFS updates on layer '%1'" ).arg( typeName );
        continue;
      }
      // start editing
      vlayer->startEditing();

Should this solve it?

Qgis::VectorProviderCapabilities cap = provider->capabilities();
      if ( 
            !( cap & Qgis::VectorProviderCapability::ChangeAttributeValues ) || 
             (vlayer->isSpatial() && !(cap & Qgis::VectorProviderCapability::ChangeGeometries ) )
         )
      {
        action.error = true;
        action.errorMsg = QStringLiteral( "No capabilities to do WFS updates on layer '%1'" ).arg( typeName );
        continue;
      }
      // start editing
      vlayer->startEditing();

[elpaso]

@gisuser0 yes: that needs the same changes, I am sorry: I only checked the getcapabilities and I assumed the transaction part was ok. I will make another PR for that.

[elpaso]

@gisuser0 this should fix the last issue: #60273