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author | 2018-02-27 23:26:26 +0800 | |
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committer | 2018-02-28 18:36:50 +0800 | |
commit | b99c0d415f37ca26443514d43f3cc1975185bf74 (patch) | |
tree | 9c53b28d8977e6752e06a9e6fdb125e2847ed735 /share/common/utils/share_lock.py | |
parent | ec6574daf067ae7ad98e7fb6e3ddf4c88d899e36 (diff) |
Move pub file from newton to common
Change-Id: Ib7160619b6fd0b1bada0da685bf4cfaa95a15fff
Issue-ID: MULTICLOUD-138
Signed-off-by: Huang Haibin <haibin.huang@intel.com>
Diffstat (limited to 'share/common/utils/share_lock.py')
-rw-r--r-- | share/common/utils/share_lock.py | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/share/common/utils/share_lock.py b/share/common/utils/share_lock.py new file mode 100644 index 00000000..7ffc7b47 --- /dev/null +++ b/share/common/utils/share_lock.py @@ -0,0 +1,77 @@ +#!/usr/bin/env python +# -*- coding: utf-8 -*- +# Copyright (c) 2017-2018 Wind River Systems, 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 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. + +import time + +import redis + +from common.config.config import REDIS_HOST, REDIS_PORT, REDIS_PASSWD + + +class SharedLock: + def __init__(self, lock_key, host=REDIS_HOST, port=REDIS_PORT, password=REDIS_PASSWD, db=9, lock_timeout=5 * 60): + self.lock_key = lock_key + self.lock_timeout = lock_timeout + self.redis = redis.Redis(host=host, port=port, db=db, password=password) + self.acquire_time = -1 + + def acquire(self): + begin = now = int(time.time()) + while (now - begin) < self.lock_timeout: + + result = self.redis.setnx(self.lock_key, now + self.lock_timeout + 1) + if result == 1 or result is True: + self.acquire_time = now + return True + + current_lock_timestamp = self.redis.get(self.lock_key) + if not current_lock_timestamp: + time.sleep(1) + continue + + current_lock_timestamp = int(current_lock_timestamp) + + if now > current_lock_timestamp: + next_lock_timestamp = self.redis.getset(self.lock_key, now + self.lock_timeout + 1) + if not next_lock_timestamp: + time.sleep(1) + continue + next_lock_timestamp = int(next_lock_timestamp) + + if next_lock_timestamp == current_lock_timestamp: + self.acquire_time = now + return True + else: + time.sleep(1) + continue + return False + + def release(self): + now = int(time.time()) + if now > self.acquire_time + self.lock_timeout: + # key expired, do nothing and let other clients handle it + return + self.acquire_time = None + self.redis.delete(self.lock_key) + + +def do_biz_with_share_lock(lock_name, callback): + lock = SharedLock(lock_name) + try: + if not lock.acquire(): + raise Exception(lock_name + " timeout") + callback() + except Exception as e: + raise e + finally: + lock.release() |