mirror of
https://github.com/langchain-ai/langgraph.git
synced 2026-08-21 07:02:25 +02:00
Nuno Campos
0d13c6b159
- Add Pregel.get_state_history and .aget_state_history methods to get history iterator - Update checkpointer base class with new list and get_tuple methods - Rewrite in-memory checkpointer class to track history - Rewrite sqlite and aiosqlite checkpointers to track history - Add new tests for history tracking
26 lines
929 B
Python
26 lines
929 B
Python
from collections import defaultdict
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from langchain_core.pydantic_v1 import Field
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from langgraph.checkpoint.base import Checkpoint, CheckpointAt, copy_checkpoint
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from langgraph.checkpoint.memory import MemorySaver
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class MemorySaverAssertImmutable(MemorySaver):
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storage_for_copies: defaultdict[str, dict[str, Checkpoint]] = Field(
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default_factory=lambda: defaultdict(dict)
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)
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at = CheckpointAt.END_OF_STEP
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def put(self, config: dict, checkpoint: Checkpoint) -> None:
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# assert checkpoint hasn't been modified since last written
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thread_id = config["configurable"]["thread_id"]
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if saved := super().get(config):
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assert self.storage_for_copies[thread_id][saved["ts"]] == saved
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self.storage_for_copies[thread_id][checkpoint["ts"]] = copy_checkpoint(
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checkpoint
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)
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# call super to write checkpoint
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super().put(config, checkpoint)
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