six_001

2026-08-02 14:07:04 +08:00
commit 046fac6dc1
339 changed files with 19435 additions and 0 deletions
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+import threading
+import time
+
+
+class SnowflakeIDGenerator:
+    # 目标：总比特数约40位，十进制最多12位（2^40 ≈ 1.1e12）
+    # 时间戳用28位（可覆盖约8.5年），机器ID用6位（64台），序列号用6位（每毫秒64个）
+    TIMESTAMP_BITS = 28
+    WORKER_ID_BITS = 6
+    SEQUENCE_BITS = 6
+
+    # 起始时间戳（2025-01-01 00:00:00 UTC），单位毫秒
+    CUSTOM_EPOCH = 1735689600000
+
+    MAX_WORKER_ID = -1 ^ (-1 << WORKER_ID_BITS)
+    MAX_SEQUENCE = -1 ^ (-1 << SEQUENCE_BITS)
+
+    # 移位计算
+    WORKER_ID_SHIFT = SEQUENCE_BITS
+    TIMESTAMP_SHIFT = SEQUENCE_BITS + WORKER_ID_BITS
+
+    def __init__(self, worker_id, sequence=0):
+        if worker_id > self.MAX_WORKER_ID or worker_id < 0:
+            raise ValueError(f"Worker ID must be between 0 and {self.MAX_WORKER_ID}")
+        self.worker_id = worker_id
+        self.sequence = sequence
+        self.last_timestamp = -1
+        self.lock = threading.Lock()
+
+    def _wait_next_ms(self, last_ts):
+        ts = self._now()
+        while ts <= last_ts:
+            ts = self._now()
+        return ts
+
+    def _now(self):
+        return int(time.time() * 1000)
+
+    def generate_id(self):
+        with self.lock:
+            ts = self._now()
+            if ts < self.last_timestamp:
+                raise Exception("Clock moved backwards")
+            if ts == self.last_timestamp:
+                self.sequence = (self.sequence + 1) & self.MAX_SEQUENCE
+                if self.sequence == 0:
+                    ts = self._wait_next_ms(self.last_timestamp)
+            else:
+                self.sequence = 0
+            self.last_timestamp = ts
+
+            # 相对时间（毫秒），只取低TIMESTAMP_BITS位
+            relative_ts = (ts - self.CUSTOM_EPOCH) & ((1 << self.TIMESTAMP_BITS) - 1)
+            new_id = (relative_ts << self.TIMESTAMP_SHIFT) | \
+                     (self.worker_id << self.WORKER_ID_SHIFT) | \
+                     self.sequence
+            return new_id
+
+    def generate_str(self):
+        return str(self.generate_id())
+
+
+# 全局生成器实例 (worker_id和datacenter_id需在分布式环境中保证唯一)
+# 单机开发环境可暂时固定，生产环境建议通过配置中心或启动参数传入
+generator = SnowflakeIDGenerator(worker_id=1)
+
+if __name__ == "__main__":
+    print(generator.generate_id())
+    print(type(generator.generate_id()))
+    print(generator.generate_str())