deb-gnocchi/gnocchi/storage/common/redis.py

128 lines
3.7 KiB
Python

# -*- encoding: utf-8 -*-
#
# Copyright © 2017 Red Hat
#
# 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
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
from __future__ import absolute_import
from six.moves.urllib import parse
from oslo_utils import strutils
try:
import redis
from redis import sentinel
except ImportError:
redis = None
sentinel = None
CLIENT_ARGS = frozenset([
'db',
'encoding',
'retry_on_timeout',
'socket_keepalive',
'socket_timeout',
'ssl',
'ssl_certfile',
'ssl_keyfile',
'sentinel',
'sentinel_fallback',
])
"""
Keys that we allow to proxy from the coordinator configuration into the
redis client (used to configure the redis client internals so that
it works as you expect/want it to).
See: http://redis-py.readthedocs.org/en/latest/#redis.Redis
See: https://github.com/andymccurdy/redis-py/blob/2.10.3/redis/client.py
"""
#: Client arguments that are expected/allowed to be lists.
CLIENT_LIST_ARGS = frozenset([
'sentinel_fallback',
])
#: Client arguments that are expected to be boolean convertible.
CLIENT_BOOL_ARGS = frozenset([
'retry_on_timeout',
'ssl',
])
#: Client arguments that are expected to be int convertible.
CLIENT_INT_ARGS = frozenset([
'db',
'socket_keepalive',
'socket_timeout',
])
#: Default socket timeout to use when none is provided.
CLIENT_DEFAULT_SOCKET_TO = 30
def get_client(conf):
if redis is None:
raise RuntimeError("python-redis unavailable")
parsed_url = parse.urlparse(conf.redis_url)
options = parse.parse_qs(parsed_url.query)
kwargs = {}
if parsed_url.hostname:
kwargs['host'] = parsed_url.hostname
if parsed_url.port:
kwargs['port'] = parsed_url.port
else:
if not parsed_url.path:
raise ValueError("Expected socket path in parsed urls path")
kwargs['unix_socket_path'] = parsed_url.path
if parsed_url.password:
kwargs['password'] = parsed_url.password
for a in CLIENT_ARGS:
if a not in options:
continue
if a in CLIENT_BOOL_ARGS:
v = strutils.bool_from_string(options[a][-1])
elif a in CLIENT_LIST_ARGS:
v = options[a][-1]
elif a in CLIENT_INT_ARGS:
v = int(options[a][-1])
else:
v = options[a][-1]
kwargs[a] = v
if 'socket_timeout' not in kwargs:
kwargs['socket_timeout'] = CLIENT_DEFAULT_SOCKET_TO
# Ask the sentinel for the current master if there is a
# sentinel arg.
if 'sentinel' in kwargs:
sentinel_hosts = [
tuple(fallback.split(':'))
for fallback in kwargs.get('sentinel_fallback', [])
]
sentinel_hosts.insert(0, (kwargs['host'], kwargs['port']))
sentinel_server = sentinel.Sentinel(
sentinel_hosts,
socket_timeout=kwargs['socket_timeout'])
sentinel_name = kwargs['sentinel']
del kwargs['sentinel']
if 'sentinel_fallback' in kwargs:
del kwargs['sentinel_fallback']
master_client = sentinel_server.master_for(sentinel_name, **kwargs)
# The master_client is a redis.StrictRedis using a
# Sentinel managed connection pool.
return master_client
return redis.StrictRedis(**kwargs)