Merge commit '47296980495f8bbfc9493e93de85dd62de6fa6b9' as 'paste-framework'

2026-06-02 19:09:22 +08:00
parent a726ea0ccd 4729698049
commit a38b5924a3
107 changed files with 21484 additions and 0 deletions
@@ -0,0 +1,126 @@
+"""
+雪花 ID 生成程序。
+"""
+
+import time
+import logging
+
+
+# 64位ID的划分
+WORKER_ID_BITS = 5
+DATACENTER_ID_BITS = 5
+SEQUENCE_BITS = 12
+
+# 最大取值计算
+MAX_WORKER_ID = -1 ^ (-1 << WORKER_ID_BITS)  # 2**5-1 0b11111
+MAX_DATACENTER_ID = -1 ^ (-1 << DATACENTER_ID_BITS)
+
+# 移位偏移计算
+WORKER_ID_SHIFT = SEQUENCE_BITS
+DATACENTER_ID_SHIFT = SEQUENCE_BITS + WORKER_ID_BITS
+TIMESTAMP_LEFT_SHIFT = SEQUENCE_BITS + WORKER_ID_BITS + DATACENTER_ID_BITS
+
+# 序号循环掩码
+SEQUENCE_MASK = -1 ^ (-1 << SEQUENCE_BITS)
+
+# Twitter元年时间戳
+TW_EPOCH = 1288834974657
+
+ID_WORKER = None
+
+
+class InvalidSystemClock(Exception):
+    """
+    时钟回拨异常
+    """
+    pass
+
+
+class IdWorker(object):
+    """
+    用于生成 Snow ID。
+    """
+
+    @classmethod
+    def get_id_worker(cls, datacenter_id=1, worker_id=1, sequence=0):
+        """
+        创建 Snow ID 对象。
+
+        :param datacenter_id: 数据中心（机器区域）ID
+        :param worker_id: 机器ID
+        :param sequence: 起始序号
+        """
+        global ID_WORKER
+        if ID_WORKER is None:
+            ID_WORKER = IdWorker(datacenter_id, worker_id, sequence)
+        return ID_WORKER
+
+    def __init__(self, datacenter_id, worker_id, sequence=0):
+        """
+        初始化。
+
+        :param datacenter_id: 数据中心（机器区域）ID
+        :param worker_id: 机器ID
+        :param sequence: 起始序号
+        """
+        # sanity check
+        if worker_id > MAX_WORKER_ID or worker_id < 0:
+            raise ValueError('worker_id值越界')
+
+        if datacenter_id > MAX_DATACENTER_ID or datacenter_id < 0:
+            raise ValueError('datacenter_id值越界')
+
+        self.worker_id = worker_id
+        self.datacenter_id = datacenter_id
+        self.sequence = sequence
+
+        self.last_timestamp = -1  # 上次计算的时间戳
+
+    @staticmethod
+    def _gen_timestamp():
+        """
+        生成整数时间戳。
+
+        :return:int timestamp
+        """
+        return int(time.time() * 1000)
+
+    def get_id(self):
+        """
+        获取新ID。
+
+        :return: 新的 Snow ID
+        """
+        timestamp = self._gen_timestamp()
+
+        # 时钟回拨
+        if timestamp < self.last_timestamp:
+            logging.error(f"时钟正在向后倒转。拒绝请求直至 {self.last_timestamp}.")
+            raise InvalidSystemClock
+
+        if timestamp == self.last_timestamp:
+            self.sequence = (self.sequence + 1) & SEQUENCE_MASK
+            if self.sequence == 0:
+                timestamp = self._til_next_millis(self.last_timestamp)
+        else:
+            self.sequence = 0
+
+        self.last_timestamp = timestamp
+
+        new_id = ((timestamp - TW_EPOCH) << TIMESTAMP_LEFT_SHIFT) | (self.datacenter_id << DATACENTER_ID_SHIFT) | \
+                 (self.worker_id << WORKER_ID_SHIFT) | self.sequence
+        return new_id
+
+    def _til_next_millis(self, last_timestamp):
+        """
+        等到下一毫秒。
+        """
+        timestamp = self._gen_timestamp()
+        while timestamp <= last_timestamp:
+            timestamp = self._gen_timestamp()
+        return timestamp
+
+
+if __name__ == '__main__':
+    worker = IdWorker(1, 1, 0)
+    print(worker.get_id())