123 lines
3.6 KiB
Python
123 lines
3.6 KiB
Python
# -*- coding: utf-8 -*-
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"""
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========================================================================================================================
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@project : my-sanic
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@file: myUUID
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@Author: mengying
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@email: 652044581@qq.com
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@date: 2023/4/4 12:14
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@desc: 雪花算法生成分布式id，用户订单生成相关或者uuid使用
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========================================================================================================================
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"""
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import time
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from threading import Lock
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# 64 位 id 的划分,通常机器位和数据位各为 5 位
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WORKER_ID_BITS = 5 # 机器位
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DATACENTER_ID_BITS = 5 # 数据位
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SEQUENCE_BITS = 12 # 循环位
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# 最大取值计算,计算机中负数表示为他的补码
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MAX_WORKER_ID = -1 ^ (-1 << WORKER_ID_BITS) # 2**5 -1 =31
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MAX_DATACENTER_ID = -1 ^ (-1 << DATACENTER_ID_BITS)
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# 移位偏移计算
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WORKER_ID_SHIFT = SEQUENCE_BITS
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DATACENTER_ID_SHIFT = SEQUENCE_BITS + WORKER_ID_BITS
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TIMESTAMP_LEFT_SHIFT = SEQUENCE_BITS + WORKER_ID_BITS + DATACENTER_ID_BITS
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# X序号循环掩码
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SEQUENCE_MASK = -1 ^ (-1 << SEQUENCE_BITS)
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# Twitter 元年时间戳
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TWEPOCH = 1288834974657
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class SingletonMeta(type):
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"""元类单例"""
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__instance = None
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__lock = Lock()
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def __call__(cls, *args, **kwargs):
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with cls.__lock:
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new = kwargs.pop('new', None)
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if new is True:
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return super().__call__(*args, **kwargs)
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if not cls.__instance:
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cls.__instance = super().__call__(*args, **kwargs)
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return cls.__instance
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class SnowIdWorker(metaclass=SingletonMeta):
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"""不能实例多次，会生产一样的id"""
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def __init__(self, datacenter_id=1, worker_id=2, sequence=0):
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"""
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初始化方法
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:param datacenter_id:数据id
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:param worker_id:机器id
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:param sequence:序列码
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"""
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if worker_id > MAX_WORKER_ID or worker_id < 0:
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raise ValueError('worker_id 值越界')
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if datacenter_id > MAX_DATACENTER_ID or datacenter_id < 0:
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raise ValueError('datacenter_id 值越界')
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self.worker_id = worker_id
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self.datacenter_id = datacenter_id
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self.sequence = sequence
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self.last_timestamp = -1 # 上次计算的时间戳
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def _gen_timestamp(self):
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"""
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生成整数时间戳。
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:return:
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"""
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return int(time.time() * 1000)
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def generate(self) -> str:
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"""
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获取新的ID.
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:return:
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"""
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# 获取当前时间戳
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timestamp = self._gen_timestamp()
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# 时钟回拨的情况
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if timestamp < self.last_timestamp:
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raise Exception("clock is moving backwards")
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if timestamp == self.last_timestamp:
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# 同一毫秒的处理。
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self.sequence = (self.sequence + 1) & SEQUENCE_MASK
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if self.sequence == 0:
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timestamp = self._til_next_millis(self.last_timestamp)
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else:
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self.sequence = 0
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self.last_timestamp = timestamp
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new_id = (((timestamp - TWEPOCH) << TIMESTAMP_LEFT_SHIFT) | (self.datacenter_id << DATACENTER_ID_SHIFT) | (
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self.worker_id << WORKER_ID_SHIFT)) | self.sequence
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return str(new_id)
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def _til_next_millis(self, last_timestamp):
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"""
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等到下一毫秒。
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:param last_timestamp:
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:return:
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"""
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timestamp = self._gen_timestamp()
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while timestamp <= last_timestamp:
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timestamp = self._gen_timestamp()
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return timestamp
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Sf = SnowIdWorker()
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if __name__ == '__main__':
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for i in range(1000):
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print(Sf.generate())
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