Add utility function QgsProjectUtils.updateLayerPath to bulk replace

a file path with a new path for all matching layers in a project
qgis · Aug 6, 2021 · 354d334 · 354d334
1 parent a31a674
commit 354d334
Show file tree

Hide file tree

Showing 4 changed files with 90 additions and 0 deletions.
diff --git a/python/core/auto_generated/project/qgsprojectutils.sip.in b/python/core/auto_generated/project/qgsprojectutils.sip.in
@@ -28,6 +28,14 @@ Contains utility functions for working with QGIS projects.
 Returns a list of all layers in the specified ``project`` which match the given ``path``.
 
 This method can be used to retrieve a list of layers in a project associated with a file path.
+%End
+
+    static bool updateLayerPath( QgsProject *project, const QString &oldPath, const QString &newPath );
+%Docstring
+Updates a ``project``, replacing the data source for all layers which match the given ``oldPath``
+with sources which point to ``newPath``.
+
+Returns ``True`` if any layers were updated as a result.
 %End
 
 };

diff --git a/src/core/project/qgsprojectutils.cpp b/src/core/project/qgsprojectutils.cpp
@@ -35,3 +35,20 @@ QList<QgsMapLayer *> QgsProjectUtils::layersMatchingPath( const QgsProject *proj
   }
   return layersList;
 }
+
+bool QgsProjectUtils::updateLayerPath( QgsProject *project, const QString &oldPath, const QString &newPath )
+{
+  if ( !project )
+    return false;
+
+  bool res = false;
+  const QMap<QString, QgsMapLayer *> mapLayers( project->mapLayers() );
+  for ( QgsMapLayer *layer : mapLayers )
+  {
+    if ( QgsMapLayerUtils::layerSourceMatchesPath( layer, oldPath ) )
+    {
+      res = QgsMapLayerUtils::updateLayerSourcePath( layer, newPath ) || res;
+    }
+  }
+  return res;
+}
diff --git a/src/core/project/qgsprojectutils.h b/src/core/project/qgsprojectutils.h
@@ -43,6 +43,14 @@ class CORE_EXPORT QgsProjectUtils
      */
     static QList< QgsMapLayer * > layersMatchingPath( const QgsProject *project, const QString &path );
 
+    /**
+     * Updates a \a project, replacing the data source for all layers which match the given \a oldPath
+     * with sources which point to \a newPath.
+     *
+     * Returns TRUE if any layers were updated as a result.
+     */
+    static bool updateLayerPath( QgsProject *project, const QString &oldPath, const QString &newPath );
+
 };
 
 #endif // QGSPROJECTUTILS_H

diff --git a/tests/src/python/test_qgsprojectutils.py b/tests/src/python/test_qgsprojectutils.py
@@ -62,6 +62,63 @@ def test_layersMatchingPath(self):
         self.assertCountEqual(QgsProjectUtils.layersMatchingPath(p, unitTestDataPath() + '/points.shp'), [layer1])
         self.assertCountEqual(QgsProjectUtils.layersMatchingPath(p, unitTestDataPath() + '/mixed_layers.gpkg'), [gpkg1, gpkg2, rl])
 
+    def test_updateLayerPath(self):
+        """
+        Test QgsProjectUtils.updateLayerPath
+        """
+        self.assertFalse(QgsProjectUtils.updateLayerPath(None, '', ''))
+        self.assertFalse(QgsProjectUtils.updateLayerPath(None, 'aaaaa', 'bbbb'))
+        p = QgsProject()
+        self.assertFalse(QgsProjectUtils.updateLayerPath(p, 'aaaaa', 'bbbb'))
+
+        # add some layers to a project
+        # shapefile
+        layer1 = QgsVectorLayer(unitTestDataPath() + '/points.shp', 'l1')
+        self.assertTrue(layer1.isValid())
+        p.addMapLayer(layer1)
+
+        gpkg1 = QgsVectorLayer(unitTestDataPath() + '/mixed_layers.gpkg|layername=lines', 'l1')
+        self.assertTrue(gpkg1.isValid())
+        p.addMapLayer(gpkg1)
+
+        gpkg2 = QgsVectorLayer(unitTestDataPath() + '/mixed_layers.gpkg|layername=points', 'l1')
+        self.assertTrue(gpkg2.isValid())
+        p.addMapLayer(gpkg2)
+
+        # raster layer from gpkg
+        rl = QgsRasterLayer(f'GPKG:{unitTestDataPath()}/mixed_layers.gpkg:band1')
+        self.assertTrue(rl.isValid())
+        p.addMapLayer(rl)
+
+        memory_layer = QgsVectorLayer("Point?field=x:string", 'my layer', "memory")
+        old_memory_source = memory_layer.source()
+        p.addMapLayer(memory_layer)
+
+        self.assertFalse(QgsProjectUtils.updateLayerPath(p, '', ''))
+        self.assertFalse(QgsProjectUtils.updateLayerPath(p, 'aaa', 'bbb'))
+
+        # replace shapefile path
+        self.assertTrue(QgsProjectUtils.updateLayerPath(p, unitTestDataPath() + '/points.shp', unitTestDataPath() + '/points22.shp'))
+        self.assertEqual(layer1.source(), unitTestDataPath() + '/points22.shp')
+        self.assertEqual(gpkg1.source(), unitTestDataPath() + '/mixed_layers.gpkg|layername=lines')
+        self.assertEqual(gpkg2.source(), unitTestDataPath() + '/mixed_layers.gpkg|layername=points')
+        self.assertEqual(rl.source(), f'GPKG:{unitTestDataPath()}/mixed_layers.gpkg:band1')
+        self.assertEqual(memory_layer.source(), old_memory_source)
+        # should return false if we call again, no more matching paths
+        self.assertFalse(QgsProjectUtils.updateLayerPath(p, unitTestDataPath() + '/points.shp',
+                                                         unitTestDataPath() + '/points22.shp'))
+
+        # replace geopackage path
+        self.assertTrue(QgsProjectUtils.updateLayerPath(p, unitTestDataPath() + '/mixed_layers.gpkg', unitTestDataPath() + '/mixed_layers22.gpkg'))
+        self.assertEqual(layer1.source(), unitTestDataPath() + '/points22.shp')
+        self.assertEqual(gpkg1.source(), unitTestDataPath() + '/mixed_layers22.gpkg|layername=lines')
+        self.assertEqual(gpkg2.source(), unitTestDataPath() + '/mixed_layers22.gpkg|layername=points')
+        self.assertEqual(rl.source(), f'GPKG:{unitTestDataPath()}/mixed_layers22.gpkg:band1')
+        self.assertEqual(memory_layer.source(), old_memory_source)
+        # should return false if we call again, no more matching paths
+        self.assertFalse(QgsProjectUtils.updateLayerPath(p, unitTestDataPath() + '/mixed_layers.gpkg',
+                                                         unitTestDataPath() + '/mixed_layers22.gpkg'))
+
 
 if __name__ == '__main__':
     unittest.main()