initial commit

venv/Lib/site-packages/langgraph/checkpoint/base/id.py

@@ -0,0 +1,109 @@
+"""Adapted from
+https://github.com/oittaa/uuid6-python/blob/main/src/uuid6/__init__.py#L95
+Bundled in to avoid install issues with uuid6 package
+"""
+
+from __future__ import annotations
+
+import random
+import time
+import uuid
+
+_last_v6_timestamp = None
+
+
+class UUID(uuid.UUID):
+    r"""UUID draft version objects"""
+
+    __slots__ = ()
+
+    def __init__(
+        self,
+        hex: str | None = None,
+        bytes: bytes | None = None,
+        bytes_le: bytes | None = None,
+        fields: tuple[int, int, int, int, int, int] | None = None,
+        int: int | None = None,
+        version: int | None = None,
+        *,
+        is_safe: uuid.SafeUUID = uuid.SafeUUID.unknown,
+    ) -> None:
+        r"""Create a UUID."""
+
+        if int is None or [hex, bytes, bytes_le, fields].count(None) != 4:
+            return super().__init__(
+                hex=hex,
+                bytes=bytes,
+                bytes_le=bytes_le,
+                fields=fields,
+                int=int,
+                version=version,
+                is_safe=is_safe,
+            )
+        if not 0 <= int < 1 << 128:
+            raise ValueError("int is out of range (need a 128-bit value)")
+        if version is not None:
+            if not 6 <= version <= 8:
+                raise ValueError("illegal version number")
+            # Set the variant to RFC 4122.
+            int &= ~(0xC000 << 48)
+            int |= 0x8000 << 48
+            # Set the version number.
+            int &= ~(0xF000 << 64)
+            int |= version << 76
+        super().__init__(int=int, is_safe=is_safe)
+
+    @property
+    def subsec(self) -> int:
+        return ((self.int >> 64) & 0x0FFF) << 8 | ((self.int >> 54) & 0xFF)
+
+    @property
+    def time(self) -> int:
+        if self.version == 6:
+            return (
+                (self.time_low << 28)
+                | (self.time_mid << 12)
+                | (self.time_hi_version & 0x0FFF)
+            )
+        if self.version == 7:
+            return self.int >> 80
+        if self.version == 8:
+            return (self.int >> 80) * 10**6 + _subsec_decode(self.subsec)
+        return super().time
+
+
+def _subsec_decode(value: int) -> int:
+    return -(-value * 10**6 // 2**20)
+
+
+def uuid6(node: int | None = None, clock_seq: int | None = None) -> UUID:
+    r"""UUID version 6 is a field-compatible version of UUIDv1, reordered for
+    improved DB locality. It is expected that UUIDv6 will primarily be
+    used in contexts where there are existing v1 UUIDs. Systems that do
+    not involve legacy UUIDv1 SHOULD consider using UUIDv7 instead.
+
+    If 'node' is not given, a random 48-bit number is chosen.
+
+    If 'clock_seq' is given, it is used as the sequence number;
+    otherwise a random 14-bit sequence number is chosen."""
+
+    global _last_v6_timestamp
+
+    nanoseconds = time.time_ns()
+    # 0x01b21dd213814000 is the number of 100-ns intervals between the
+    # UUID epoch 1582-10-15 00:00:00 and the Unix epoch 1970-01-01 00:00:00.
+    timestamp = nanoseconds // 100 + 0x01B21DD213814000
+    if _last_v6_timestamp is not None and timestamp <= _last_v6_timestamp:
+        timestamp = _last_v6_timestamp + 1
+    _last_v6_timestamp = timestamp
+    if clock_seq is None:
+        clock_seq = random.getrandbits(14)  # instead of stable storage
+    if node is None:
+        node = random.getrandbits(48)
+    time_high_and_time_mid = (timestamp >> 12) & 0xFFFFFFFFFFFF
+    time_low_and_version = timestamp & 0x0FFF
+    uuid_int = time_high_and_time_mid << 80
+    uuid_int |= time_low_and_version << 64
+    uuid_int |= (clock_seq & 0x3FFF) << 48
+    uuid_int |= node & 0xFFFFFFFFFFFF
+    return UUID(int=uuid_int, version=6)