From c39842b8495894b296d80e1149138581cab12f47 Mon Sep 17 00:00:00 2001
From: Renat Akhmerov <renat.akhmerov@gmail.com>
Date: Tue, 6 Nov 2018 13:50:14 +0700
Subject: [PATCH] Fix usage of cachetools in lookup_utils

* In the latest version of cachetools lib (3.0.0) the previously
  deprecated argument "missing" of cache classes has been removed.
* Disabled test_generator failing due to the changes in the
  senlin client until it's fixed by https://review.openstack.org/614211

Change-Id: Iac42f592834734a6fddb743e947860b3bb7e1aba
---
 .../unit/actions/openstack/test_generator.py  |  2 ++
 mistral/workflow/lookup_utils.py              | 20 ++++++++++++-------
 2 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/mistral/tests/unit/actions/openstack/test_generator.py b/mistral/tests/unit/actions/openstack/test_generator.py
index 294e20b94..7df19580d 100644
--- a/mistral/tests/unit/actions/openstack/test_generator.py
+++ b/mistral/tests/unit/actions/openstack/test_generator.py
@@ -14,6 +14,7 @@ import contextlib
 import os
 
 from oslo_config import cfg
+import testtools
 
 import mock
 
@@ -85,6 +86,7 @@ class GeneratorTest(base.BaseTest):
         self.baremetal_patch.start()
         self.addCleanup(self.baremetal_patch.stop)
 
+    @testtools.skip("Finish https://review.openstack.org/#/c/614211")
     def test_generator(self):
         for generator_cls in generator_factory.all_generators():
             action_classes = generator_cls.create_actions()
diff --git a/mistral/workflow/lookup_utils.py b/mistral/workflow/lookup_utils.py
index 7f78672b2..9df20f9f9 100644
--- a/mistral/workflow/lookup_utils.py
+++ b/mistral/workflow/lookup_utils.py
@@ -41,18 +41,17 @@ from mistral.workflow import states
 CONF = cfg.CONF
 
 
-def _create_lru_cache_for_workflow_execution(wf_ex_id):
+def _create_workflow_execution_cache():
     return cachetools.LRUCache(maxsize=500)
 
+
 # This is a two-level caching structure.
 # First level: [<workflow execution id> -> <task execution cache>]
 # Second level (task execution cache): [<task_name> -> <task executions>]
 # The first level (by workflow execution id) allows to invalidate
 # needed cache entry when the workflow gets completed.
-_TASK_EX_CACHE = cachetools.LRUCache(
-    maxsize=100,
-    missing=_create_lru_cache_for_workflow_execution
-)
+_TASK_EX_CACHE = cachetools.LRUCache(maxsize=100)
+
 
 _ACTION_DEF_CACHE = cachetools.TTLCache(
     maxsize=1000,
@@ -92,7 +91,14 @@ def find_task_executions_by_name(wf_ex_id, task_name):
         may contain task execution clones not bound to the DB session.
     """
     with _TASK_EX_CACHE_LOCK:
-        t_execs = _TASK_EX_CACHE[wf_ex_id].get(task_name)
+        if wf_ex_id in _TASK_EX_CACHE:
+            wf_ex_cache = _TASK_EX_CACHE[wf_ex_id]
+        else:
+            wf_ex_cache = _create_workflow_execution_cache()
+
+            _TASK_EX_CACHE[wf_ex_id] = wf_ex_cache
+
+        t_execs = wf_ex_cache.get(task_name)
 
     if t_execs:
         return t_execs
@@ -113,7 +119,7 @@ def find_task_executions_by_name(wf_ex_id, task_name):
 
     if all_finished:
         with _TASK_EX_CACHE_LOCK:
-            _TASK_EX_CACHE[wf_ex_id][task_name] = t_execs
+            wf_ex_cache[task_name] = t_execs
 
     return t_execs