openstack/deb-aodh
Code Issues Proposed changes

mongodb: replace custom retry code by retrying

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Change-Id: I01936838cd32173c70a3052f6156bae829015ff4
This commit is contained in:
Julien Danjou 2015-07-26 17:09:45 +02:00
parent e5db4b75f1
commit bed80141c1
1 changed files with 21 additions and 39 deletions
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60
aodh/storage/mongo/utils.py
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@ -1,8 +1,6 @@
#
# Copyright Ericsson AB 2013. All rights reserved
#
# Authors: Ildiko Vancsa <ildiko.vancsa@ericsson.com>
# Balazs Gibizer <balazs.gibizer@ericsson.com>
# Copyright 2015 Red Hat, Inc
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
@ -18,13 +16,13 @@
"""Common functions for MongoDB and DB2 backends
"""
import time
import weakref
from oslo_config import cfg
from oslo_log import log
from oslo_utils import netutils
import pymongo
import retrying
from aodh.i18n import _
@ -221,37 +219,6 @@ class QueryTransformer(object):
return self._handle_simple_op(operator_node, nodes)
def safe_mongo_call(call):
def closure(*args, **kwargs):
max_retries = cfg.CONF.database.max_retries
retry_interval = cfg.CONF.database.retry_interval
attempts = 0
while True:
try:
return call(*args, **kwargs)
except pymongo.errors.AutoReconnect as err:
if 0 <= max_retries <= attempts:
LOG.error(_('Unable to reconnect to the primary mongodb '
'after %(retries)d retries. Giving up.') %
{'retries': max_retries})
raise
LOG.warn(_('Unable to reconnect to the primary mongodb: '
'%(errmsg)s. Trying again in %(retry_interval)d '
'seconds.') %
{'errmsg': err, 'retry_interval': retry_interval})
attempts += 1
time.sleep(retry_interval)
return closure
class MongoConn(object):
def __init__(self, method):
self.method = method
@safe_mongo_call
def __call__(self, *args, **kwargs):
return self.method(*args, **kwargs)
MONGO_METHODS = set([typ for typ in dir(pymongo.collection.Collection)
if not typ.startswith('_')])
MONGO_METHODS.update(set([typ for typ in dir(pymongo.MongoClient)
@ -260,6 +227,15 @@ MONGO_METHODS.update(set([typ for typ in dir(pymongo)
if not typ.startswith('_')]))
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
)
class MongoProxy(object):
def __init__(self, conn):
self.conn = conn
@ -281,13 +257,16 @@ class MongoProxy(object):
"""Wrap MongoDB connection.
If item is the name of an executable method, for example find or
insert, wrap this method in the MongoConn.
insert, wrap this method to retry.
Else wrap getting attribute with MongoProxy.
"""
if item in ('name', 'database'):
return getattr(self.conn, item)
if item in MONGO_METHODS:
return MongoConn(getattr(self.conn, item))
return _safe_mongo_call(
cfg.CONF.database.max_retries,
cfg.CONF.database.retry_interval,
)(getattr(self.conn, item))
return MongoProxy(getattr(self.conn, item))
def __call__(self, *args, **kwargs):
@ -297,12 +276,15 @@ class MongoProxy(object):
class CursorProxy(pymongo.cursor.Cursor):
def __init__(self, cursor):
self.cursor = cursor
self.next = _safe_mongo_call(
cfg.CONF.database.max_retries,
cfg.CONF.database.retry_interval,
)(self._next)
def __getitem__(self, item):
return self.cursor[item]
@safe_mongo_call
def next(self):
def _next(self):
"""Wrap Cursor next method.
This method will be executed before each Cursor next method call.