[processing] do not allow editing model if it's missing algorithms

volaya · volaya · commit a86965e94bc7 · 2019-01-23T14:02:42.000+01:00
fixes #19607
diff --git a/python/plugins/processing/modeler/EditModelAction.py b/python/plugins/processing/modeler/EditModelAction.py
@@ -26,9 +26,11 @@
 __revision__ = '$Format:%H$'
 
 from qgis.PyQt.QtCore import QCoreApplication
-from qgis.core import QgsApplication, QgsProcessingModelAlgorithm
+from qgis.core import QgsApplication, QgsProcessingModelAlgorithm, QgsMessageLog
 from processing.gui.ContextAction import ContextAction
 from processing.modeler.ModelerDialog import ModelerDialog
+from qgis.core import Qgis
+from qgis.utils import iface
 
 
 class EditModelAction(ContextAction):
@@ -41,9 +43,13 @@ def isEnabled(self):
 
     def execute(self):
         alg = self.itemData
-        dlg = ModelerDialog(alg)
-        dlg.update_model.connect(self.updateModel)
-        dlg.show()
+        ok, msg = alg.canExecute()
+        if not ok:
+            iface.messageBar().pushMessage("Cannot edit model:", msg, level=Qgis.Warning)
+        else:
+            dlg = ModelerDialog(alg)
+            dlg.update_model.connect(self.updateModel)
+            dlg.show()
 
     def updateModel(self):
         QgsApplication.processingRegistry().providerById('model').refreshAlgorithms()
