From a57db4e64ad154aeecb62adffc2a735966e44d37 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E2=80=9Czhangshengping2012=E2=80=9D?=
 <zhangshengping@unitedstack.com>
Date: Wed, 7 Dec 2016 17:49:07 +0800
Subject: [PATCH] Replace all retrying with tenacity in Panko

Change-Id: I7e61fa4dad70801cdbc1f543fe18d7c1a64116b0
---
 panko/storage/__init__.py                       | 10 ++++++----
 panko/storage/mongo/utils.py                    | 13 +++++++------
 panko/tests/unit/storage/test_get_connection.py | 17 +++++++++--------
 requirements.txt                                |  2 +-
 4 files changed, 23 insertions(+), 19 deletions(-)

diff --git a/panko/storage/__init__.py b/panko/storage/__init__.py
index bfdfb251..dac22042 100644
--- a/panko/storage/__init__.py
+++ b/panko/storage/__init__.py
@@ -17,9 +17,9 @@
 
 from oslo_config import cfg
 from oslo_log import log
-import retrying
 import six.moves.urllib.parse as urlparse
 from stevedore import driver
+import tenacity
 
 
 LOG = log.getLogger(__name__)
@@ -57,9 +57,11 @@ class InvalidMarker(Exception):
 def get_connection_from_config(conf):
     retries = conf.database.max_retries
 
-    # Convert retry_interval secs to msecs for retry decorator
-    @retrying.retry(wait_fixed=conf.database.retry_interval * 1000,
-                    stop_max_attempt_number=retries if retries >= 0 else None)
+    @tenacity.retry(
+        wait=tenacity.wait_fixed(conf.database.retry_interval),
+        stop=(tenacity.stop_after_attempt(retries) if retries >= 0
+              else tenacity.stop_never)
+    )
     def _inner():
         url = (getattr(conf.database, 'event_connection') or
                conf.database.connection)
diff --git a/panko/storage/mongo/utils.py b/panko/storage/mongo/utils.py
index 75f27a4e..791a2afa 100644
--- a/panko/storage/mongo/utils.py
+++ b/panko/storage/mongo/utils.py
@@ -21,8 +21,8 @@ from oslo_log import log
 from oslo_utils import netutils
 import pymongo
 import pymongo.errors
-import retrying
 import six
+import tenacity
 
 from panko.i18n import _, _LI
 
@@ -145,11 +145,12 @@ class ConnectionPool(object):
 
 
 def _safe_mongo_call(max_retries, retry_interval):
-    return retrying.retry(
-        retry_on_exception=lambda e: isinstance(
-            e, pymongo.errors.AutoReconnect),
-        wait_fixed=retry_interval * 1000,
-        stop_max_attempt_number=max_retries if max_retries >= 0 else None
+    return tenacity.retry(
+        retry=tenacity.retry_if_exception_type(
+            pymongo.errors.AutoReconnect),
+        wait=tenacity.wait_fixed(retry_interval),
+        stop=(tenacity.stop_after_attempt(max_retries) if max_retries >= 0
+              else tenacity.stop_never)
     )
 
 
diff --git a/panko/tests/unit/storage/test_get_connection.py b/panko/tests/unit/storage/test_get_connection.py
index e1c4496d..b4c771b0 100644
--- a/panko/tests/unit/storage/test_get_connection.py
+++ b/panko/tests/unit/storage/test_get_connection.py
@@ -17,7 +17,6 @@
 
 import mock
 from oslotest import base
-import retrying
 
 from panko.event.storage import impl_log
 from panko.event.storage import impl_sqlalchemy
@@ -45,17 +44,19 @@ class ConnectionRetryTest(base.BaseTestCase):
         self.CONF = service.prepare_service([], config_files=[])
 
     def test_retries(self):
-        with mock.patch.object(
-                retrying.Retrying, 'should_reject') as retry_reject:
+        # stevedore gives warning log instead of any exception
+        with mock.patch.object(storage, 'get_connection',
+                               side_effect=Exception) as retries:
             try:
-                self.CONF.set_override("connection", "no-such-engine://",
+                self.CONF.set_override("retry_interval", 1,
                                        group="database")
-                self.CONF.set_override("retry_interval", 0.00001,
+                self.CONF.set_override("max_retries", 3,
                                        group="database")
                 storage.get_connection_from_config(self.CONF)
-            except RuntimeError as err:
-                self.assertIn('no-such-engine', six.text_type(err))
-                self.assertEqual(10, retry_reject.call_count)
+            except Exception:
+                self.assertEqual(3, retries.call_count)
+            else:
+                self.fail()
 
 
 class ConnectionConfigTest(base.BaseTestCase):
diff --git a/requirements.txt b/requirements.txt
index 9284ce75..008abc11 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -3,7 +3,7 @@
 # process, which may cause wedges in the gate later.
 
 debtcollector>=1.2.0  # Apache-2.0
-retrying!=1.3.0,>=1.2.3 # Apache-2.0
+tenacity>=3.1.0 # Apache-2.0
 keystonemiddleware!=4.1.0,>=4.0.0 # Apache-2.0
 lxml>=2.3 # BSD
 oslo.db>=4.1.0 # Apache-2.0