Fix issue when using workflows transitions with the new version upload event as trigger. Thanks to Sema @Miggaten for the find and the solution.

Signed-off-by: Roberto Rosario <roberto.rosario.gonzalez@gmail.com>

HISTORY.rst

@@ -137,6 +137,9 @@
 - Improve line chart appearance. Fix mouse hover label issue.
 - Add JavaScript dependency manager.
 - Add support for passing arguments to the OCR backend.
+- Fix issue when using workflows transitions with the new version
+  upload event as trigger. Thanks to Sema @Miggaten for the find and
+  the solution.
 
 2.7.3 (2017-09-11)
 ==================

docs/releases/3.0.rst

@@ -427,7 +427,9 @@ Other changes worth mentioning
 - Update Chart.js version.
 - Improve line chart appearance. Fix issue with mouse over labels next other chart margin.
 - Add support for passing arguments to the OCR backend.
-
+- Fix issue when using workflows transitions with the new version
+  upload event as trigger. Thanks to Sema @Miggaten for the find and
+  the solution.
 
 
 Removals

mayan/apps/document_states/handlers.py

@@ -39,12 +39,12 @@ def handler_trigger_transition(sender, **kwargs):
 
     for workflow_instance in workflow_instances:
         # Select the first transition that is valid for this workflow state
-        transition = list(set(trigger_transitions) & set(workflow_instance.get_transition_choices()))[0]
+        valid_transitions = list(set(trigger_transitions) & set(workflow_instance.get_transition_choices()))
-
+        if valid_transitions:
-        workflow_instance.do_transition(
+            workflow_instance.do_transition(
-            comment=_('Event trigger: %s') % EventType.get(name=action.verb).label,
+                comment=_('Event trigger: %s') % EventType.get(name=action.verb).label,
-            transition=transition
+                transition=valid_transitions[0]
-        )
+            )
 
 
 def launch_workflow(sender, instance, created, **kwargs):