workflows: fix external workflow when slug is wrong (#51276)

tests/test_workflows.py

@@ -6286,6 +6286,23 @@ def test_call_external_workflow_manual_targeting(two_pubs):
     logged_error = two_pubs.loggederror_class.select()[0]
     assert logged_error.summary == 'Could not find targeted "Data" object by id 421'
 
+    # slug not or badly configured
+    update_action.target_id = '{{ form_var_string }}'  # == '1'
+    update_action.slug = None
+    wf.store()
+    perform_items([update_action], formdata)
+    assert carddef.data_class().get(1).data['bo0'] == '1'  # not changed
+    assert carddef.data_class().get(2).data['bo0'] is None
+    assert carddef.data_class().get(3).data['bo0'] is None
+    assert carddef.data_class().get(4).data['bo0'] is None
+    update_action.slug = 'foo'
+    wf.store()
+    perform_items([update_action], formdata)
+    assert carddef.data_class().get(1).data['bo0'] == '1'  # not changed
+    assert carddef.data_class().get(2).data['bo0'] is None
+    assert carddef.data_class().get(3).data['bo0'] is None
+    assert carddef.data_class().get(4).data['bo0'] is None
+
 
 def test_edit_carddata_with_data_sourced_object(pub):
     FormDef.wipe()

wcs/wf/external_workflow.py

@@ -48,7 +48,10 @@ class ExternalWorkflowGlobalAction(WorkflowStatusItem):
 
     def get_object_def(self, object_slug=None):
         slug = object_slug or self.slug
-        object_type, slug = slug.split(':')
+        try:
+            object_type, slug = slug.split(':')
+        except (AttributeError, ValueError):
+            return None
         if object_type == 'formdef':
             object_class = FormDef
         elif object_type == 'carddef':