Import processing from qgis package

Processing is not importable without modifying search paths.
At qgis initialization time processing modules are monkeypatched
to qgis module where those are supposed to be imported.

Author: LKajan

nlsgpkgloader/nls_geopackage_loader_tasks.py

@@ -20,13 +20,13 @@
 import os
 import sqlite3
 
-import processing  # pylint: disable=import-error
 from osgeo import ogr
-from processing.tools import dataobjects  # pylint: disable=import-error
+from qgis import processing
 from qgis.core import (
     QgsFeature,
     QgsFeatureRequest,
     QgsMessageLog,
+    QgsProcessingContext,
     QgsTask,
     QgsVectorFileWriter,
     QgsVectorLayer,
@@ -180,7 +180,8 @@ def run(self):
                 + layer_name
                 + '" (geom) sql=',
             }
-            context = dataobjects.createContext()
+
+            context = QgsProcessingContext()
             context.setInvalidGeometryCheck(QgsFeatureRequest.GeometrySkipInvalid)
             processing.run("native:dissolve", params, context=context)
             percentage = i / float(total_tables) * 100.0