Remove all running workflow instances from documents whose type is removed from the workflow type. This avoid having orphaned workflows running.

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

HISTORY.rst

@@ -140,6 +140,9 @@
 - Fix issue when using workflows transitions with the new version
   upload event as trigger. Thanks to Sema @Miggaten for the find and
   the solution.
+- Removing running workflow instances in document of a specific type if
+  that document type is removed from the workflow.
+  
 
 2.7.3 (2017-09-11)
 ==================

docs/releases/3.0.rst

@@ -325,6 +325,10 @@ allows apps to specify their own dependencies. These dependecies are then
 downloaded when the project is installed or upgraded. As such they are not
 part of the repository and lower the file size of the project.
 
+Workflow changes
+----------------
+Removing a document type from a workflow will now also remove all running
+instances of that workflow for documents of the document type just removed.
 
 Other changes worth mentioning
 ------------------------------
@@ -340,7 +344,8 @@ Other changes worth mentioning
 - Update to the latest version the packages for building, development, documentation and testing.
 - Add statistics script to produce a report of the views, APIs and test for each app.
 - Merge base64 filename patch from Cornelius Ludmann.
-- SearchModel return interface changed. The class no longer returns the result_set value. Use the queryset returned instead.
+- SearchModel return interface changed. The class no longer
+  returns the result_set value. Use the queryset returned instead.
 - Remove the unused scrollable_content internal feature.
 - Remove unused animate.css package.
 - Add the MERC specifying javascript library usage.

mayan/apps/document_states/views.py

@@ -2,6 +2,7 @@ from __future__ import absolute_import, unicode_literals
 
 from django.contrib import messages
 from django.core.files.base import ContentFile
+from django.db import transaction
 from django.db.utils import IntegrityError
 from django.http import Http404, HttpResponseRedirect
 from django.shortcuts import get_object_or_404
@@ -176,6 +177,17 @@ class SetupWorkflowDocumentTypesView(AssignRemoveView):
         # TODO: add task launching this workflow for all the document types
         # of item
 
+    def dispatch(self, request, *args, **kwargs):
+        messages.warning(
+            self.request, _(
+                'Removing a document type from a workflow will also '
+                'remove all running instances of that workflow for '
+                'documents of the document type just removed.'
+            )
+        )
+
+        return super(SetupWorkflowDocumentTypesView, self).dispatch(request, *args, **kwargs)
+
     def get_extra_context(self):
         return {
             'title': _(
@@ -198,9 +210,11 @@ class SetupWorkflowDocumentTypesView(AssignRemoveView):
         )
 
     def remove(self, item):
-        self.get_object().document_types.remove(item)
-        # TODO: add task deleting this workflow for all the document types of
-        # item
+        # When removing a document type to workflow association
+        # also remove all running workflows in documents of that type.
+        with transaction.atomic():
+            self.get_object().document_types.remove(item)
+            self.get_object().instances.filter(document__document_type=item).delete()
 
 
 # Workflow state actions