From 663092d675bca7c2420665b820db9306e381d73f Mon Sep 17 00:00:00 2001
From: Julien Danjou <julien@danjou.info>
Date: Tue, 17 May 2016 09:55:26 +0200
Subject: [PATCH] api: always enable retry_on_request

The current behavior makes by default retry_on_request does not work,
which is confusing. Nothing except the developer can raise a
RetryRequest, so there can not be any misunderstanding. Having to both
enable the switch *and* raise RetryRequest makes it more complicated
than it needs to be.

This patch simplifies the API by deprecating retry_on_request and
retry_on_request() decorator, enabling the exception everywhere
wrap_db_retry() is used.

Change-Id: I3c53b5c8ba99f460153256fb2e1e6ef01b67f41b
---
 oslo_db/api.py            | 10 +++++-----
 oslo_db/tests/test_api.py |  6 +++---
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/oslo_db/api.py b/oslo_db/api.py
index 8cab3e57..6a58394c 100644
--- a/oslo_db/api.py
+++ b/oslo_db/api.py
@@ -27,6 +27,7 @@ import logging
 import threading
 import time
 
+from debtcollector import removals
 from oslo_utils import excutils
 from oslo_utils import importutils
 from oslo_utils import reflection
@@ -106,6 +107,8 @@ class wrap_db_retry(object):
     :type exception_checker: callable
     """
 
+    @removals.removed_kwarg("retry_on_request",
+                            "Retry on request is always enabled")
     def __init__(self, retry_interval=0, max_retries=0,
                  inc_retry_interval=False,
                  max_retry_interval=0, retry_on_disconnect=False,
@@ -113,15 +116,13 @@ class wrap_db_retry(object):
                  exception_checker=lambda exc: False):
         super(wrap_db_retry, self).__init__()
 
-        self.db_error = ()
+        self.db_error = (exception.RetryRequest, )
         # default is that we re-raise anything unexpected
         self.exception_checker = exception_checker
         if retry_on_disconnect:
             self.db_error += (exception.DBConnectionError, )
         if retry_on_deadlock:
             self.db_error += (exception.DBDeadlock, )
-        if retry_on_request:
-            self.db_error += (exception.RetryRequest, )
         self.retry_interval = retry_interval
         self.max_retries = max_retries
         self.inc_retry_interval = inc_retry_interval
@@ -258,8 +259,7 @@ class DBAPI(object):
                 inc_retry_interval=self.inc_retry_interval,
                 max_retry_interval=self.max_retry_interval,
                 retry_on_disconnect=retry_on_disconnect,
-                retry_on_deadlock=retry_on_deadlock,
-                retry_on_request=retry_on_request)(attr)
+                retry_on_deadlock=retry_on_deadlock)(attr)
 
         return attr
 
diff --git a/oslo_db/tests/test_api.py b/oslo_db/tests/test_api.py
index 6b13bae2..ab33c8c8 100644
--- a/oslo_db/tests/test_api.py
+++ b/oslo_db/tests/test_api.py
@@ -200,7 +200,7 @@ class DBReconnectTestCase(DBAPITestCase):
 
 class DBRetryRequestCase(DBAPITestCase):
     def test_retry_wrapper_succeeds(self):
-        @api.wrap_db_retry(max_retries=10, retry_on_request=True)
+        @api.wrap_db_retry(max_retries=10)
         def some_method():
             pass
 
@@ -209,7 +209,7 @@ class DBRetryRequestCase(DBAPITestCase):
     def test_retry_wrapper_reaches_limit(self):
         max_retries = 10
 
-        @api.wrap_db_retry(max_retries=10, retry_on_request=True)
+        @api.wrap_db_retry(max_retries=10)
         def some_method(res):
             res['result'] += 1
             raise exception.RetryRequest(ValueError())
@@ -223,7 +223,7 @@ class DBRetryRequestCase(DBAPITestCase):
         def exception_checker(exc):
             return isinstance(exc, ValueError) and exc.args[0] < 5
 
-        @api.wrap_db_retry(max_retries=10, retry_on_request=True,
+        @api.wrap_db_retry(max_retries=10,
                            exception_checker=exception_checker)
         def some_method(res):
             res['result'] += 1