Cancel Action Plan

This patch adds feature to cancel action plan in watcher.
A General flow from watcher-api to watcher-applier is implemented.

action plan cancel can cancel any [ongoing, pending, recommended]
action plan, it will update the action states also to "cancelled".
For ongoing actions in action plan, actions needs to be aborted.
Seperate patches will be added to support abort operation
in each action.

Notification part is addressed by a seperate blueprint.
https://blueprints.launchpad.net/watcher/+spec/notifications-actionplan-cancel

Change-Id: I895a5eaca5239d5657702c8d1875b9ece21682dc
Partially-Implements: blueprint cancel-action-plan

watcher/api/controllers/v1/action_plan.py

@@ -488,6 +488,7 @@ class ActionPlansController(rest.RestController):
             raise exception.PatchError(patch=patch, reason=e)
 
         launch_action_plan = False
+        cancel_action_plan = False
 
         # transitions that are allowed via PATCH
         allowed_patch_transitions = [
@@ -496,7 +497,7 @@ class ActionPlansController(rest.RestController):
             (ap_objects.State.RECOMMENDED,
              ap_objects.State.CANCELLED),
             (ap_objects.State.ONGOING,
-             ap_objects.State.CANCELLED),
+             ap_objects.State.CANCELLING),
             (ap_objects.State.PENDING,
              ap_objects.State.CANCELLED),
         ]
@@ -515,6 +516,8 @@ class ActionPlansController(rest.RestController):
 
             if action_plan.state == ap_objects.State.PENDING:
                 launch_action_plan = True
+            if action_plan.state == ap_objects.State.CANCELLED:
+                cancel_action_plan = True
 
         # Update only the fields that have changed
         for field in objects.ActionPlan.fields:
@@ -534,6 +537,16 @@ class ActionPlansController(rest.RestController):
 
         action_plan_to_update.save()
 
+        # NOTE: if action plan is cancelled from pending or recommended
+        # state update action state here only
+        if cancel_action_plan:
+            filters = {'action_plan_uuid': action_plan.uuid}
+            actions = objects.Action.list(pecan.request.context,
+                                          filters=filters, eager=True)
+            for a in actions:
+                a.state = objects.action.State.CANCELLED
+                a.save()
+
         if launch_action_plan:
             applier_client = rpcapi.ApplierAPI()
             applier_client.launch_action_plan(pecan.request.context,