mgr/rbd_support: avoid using list of different type of elements

refactor Schedules.find() to avoid using list composed of different
types of elements. this annoys mypy.

also take this opportunity to avoid looking up in the dict twice.

Signed-off-by: Kefu Chai <kchai@redhat.com>

diff --git a/src/pybind/mgr/rbd_support/schedule.py b/src/pybind/mgr/rbd_support/schedule.py
index eaee182cb04e5f645448c138299b770ceeb04614..50e0f6cdc4481e26e3a5258cc85944ef98978f8e 100644 (file)
--- a/src/pybind/mgr/rbd_support/schedule.py
+++ b/src/pybind/mgr/rbd_support/schedule.py
@@ -473,15 +473,17 @@ class Schedules:
         self.save(level_spec, schedule)
 
     def find(self, pool_id, namespace, image_id=None):
-        levels = [None, pool_id, namespace]
+        levels = [pool_id, namespace]
         if image_id:
             levels.append(image_id)
-
-        while levels:
-            level_spec_id = "/".join(levels[1:])
-            if level_spec_id in self.schedules:
-                return self.schedules[level_spec_id]
-            del levels[-1]
+        nr_levels = len(levels)
+        while nr_levels >= 0:
+            # an empty spec id implies global schedule
+            level_spec_id = "/".join(levels[:nr_levels])
+            found = self.schedules.get(level_spec_id)
+            if found is not None:
+                return found
+            nr_levels -= 1
         return None
 
     def intersects(self, level_spec):