2 # -*- coding: utf-8 -*-
3 # Copyright (c) 2017 Wind River Systems, Inc.
4 # Copyright (c) 2017-2018 VMware, Inc.
6 # Licensed under the Apache License, Version 2.0 (the "License");
7 # you may not use this file except in compliance with the License.
8 # You may obtain a copy of the License at:
9 # http://www.apache.org/licenses/LICENSE-2.0
11 # Unless required by applicable law or agreed to in writing, software
12 # distributed under the License is distributed on an "AS IS" BASIS,
13 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
19 from multivimbroker.pub.config.config import REDIS_HOST
20 from multivimbroker.pub.config.config import REDIS_PORT
21 from multivimbroker.pub.config.config import REDIS_PASSWD
25 def __init__(self, lock_key, host=REDIS_HOST, port=REDIS_PORT,
26 password=REDIS_PASSWD, db=9, lock_timeout=5 * 60):
27 self.lock_key = lock_key
28 self.lock_timeout = lock_timeout
29 self.redis = redis.Redis(host=host, port=port,
30 db=db, password=password)
31 self.acquire_time = -1
34 begin = now = int(time.time())
35 while (now - begin) < self.lock_timeout:
37 result = self.redis.setnx(self.lock_key, now +
38 self.lock_timeout + 1)
39 if result == 1 or result is True:
40 self.acquire_time = now
43 current_lock_timestamp = self.redis.get(self.lock_key)
44 if not current_lock_timestamp:
48 current_lock_timestamp = int(current_lock_timestamp)
50 if now > current_lock_timestamp:
51 next_lock_timestamp = self.redis.getset(self.lock_key, now +
52 self.lock_timeout + 1)
53 if not next_lock_timestamp:
56 next_lock_timestamp = int(next_lock_timestamp)
58 if next_lock_timestamp == current_lock_timestamp:
59 self.acquire_time = now
67 now = int(time.time())
68 if now > self.acquire_time + self.lock_timeout:
69 # key expired, do nothing and let other clients handle it
71 self.acquire_time = None
72 self.redis.delete(self.lock_key)
75 def do_biz_with_share_lock(lock_name, callback):
76 lock = SharedLock(lock_name)
78 if not lock.acquire():
79 raise Exception(lock_name + " timeout")
81 except Exception as e: