Push error in case the geometry has Z but the layer has not

src/providers/wfs/qgsbackgroundcachedfeatureiterator.cpp

@@ -572,8 +572,21 @@ void QgsBackgroundCachedFeatureIterator::featureReceivedSynchronous( const QVect
     mWriterStream.reset( new QDataStream( &mWriterByteArray, QIODevice::WriteOnly ) );
   }
   const auto constList = list;
+  const Qgis::WkbType expectedType { mShared->mWKBType };
+  bool errorRaised = false;
   for ( const QgsFeatureUniqueIdPair &pair : constList )
   {
+    if ( !errorRaised && expectedType != pair.first.geometry().wkbType() )
+    {
+      if ( QgsWkbTypes::hasZ( pair.first.geometry().wkbType() ) && !QgsWkbTypes::hasZ( expectedType ) )
+      {
+        mShared->pushError( QStringLiteral( "Received feature geometry has Z values but the layer type (%1) does not. Please check the WFS connection setting 'Force initial GetFeature'." ).arg( QgsWkbTypes::displayString( expectedType ) ) );
+      }
+      else
+      {
+        mShared->pushError( QStringLiteral( "Received feature with geometry type %1, expected %2" ).arg( QgsWkbTypes::displayString( pair.first.geometry().wkbType() ), QgsWkbTypes::displayString( expectedType ) ) );
+      }
+    }
     *mWriterStream << pair.first;
   }
   if ( !mWriterFile && mWriterByteArray.size() > mWriteTransferThreshold )

src/providers/wfs/qgsbackgroundcachedshareddata.h

@@ -188,6 +188,9 @@ class QgsBackgroundCachedSharedData
     //! Called when an error must be raised to the provider
     virtual void pushError( const QString &errorMsg ) const = 0;
 
+    //! Geometry type of the features in this layer (used by WFS only)
+    Qgis::WkbType mWKBType = Qgis::WkbType::Unknown;
+
   protected:
     //////////// Input members. Implementations should define them to meaningful values
 

src/providers/wfs/qgswfsprovidermetadata.cpp

@@ -245,7 +245,7 @@ QList<QgsProviderSublayerDetails> QgsWfsProviderMetadata::querySublayers( const
   details.setWkbType( provider.wkbType() );
   res << details;
 
-  // Always issue a GetFeature because the guessed type can't be trusted,
+  // If set: always issue a GetFeature because the guessed type can't be trusted,
   // for example when dealing with Z geometries identified as 2D.
   const bool forceInitialGetFeature = dsUri.hasParam( QgsWFSConstants::URI_PARAM_FORCE_INITIAL_GET_FEATURE )
                                       && dsUri.param( QgsWFSConstants::URI_PARAM_FORCE_INITIAL_GET_FEATURE ).toUpper() == QStringLiteral( "TRUE" );

src/providers/wfs/qgswfsshareddata.h

@@ -141,9 +141,6 @@ class QgsWFSSharedData : public QObject, public QgsBackgroundCachedSharedData
      */
     bool mServerPrefersCoordinatesForTransactions_1_1 = false;
 
-    //! Geometry type of the features in this layer
-    Qgis::WkbType mWKBType = Qgis::WkbType::Unknown;
-
     //! Geometry type filter to ensure geometries returned by the layer are of type mWKBType.
     QString mWFSGeometryTypeFilter;