Files
langgraph/libs/langgraph/tests/memory_assert.py
T
Nuno Campos 46b652a74c Use incremental storage in memory checkpointer
- This makes our checkpoint benchmarks more closely resemble the behavior of our prod checkpointers
- Also found and fixed a bug w multiple subgraphs in same node accidentally sharing checkpoints
2025-03-20 16:11:36 -07:00

78 lines
2.4 KiB
Python

import os
import tempfile
from collections import defaultdict
from functools import partial
from typing import Any, Optional
from langchain_core.runnables import RunnableConfig
from langgraph.checkpoint.base import (
ChannelVersions,
Checkpoint,
CheckpointMetadata,
CheckpointTuple,
SerializerProtocol,
)
from langgraph.checkpoint.memory import InMemorySaver, PersistentDict
class NoopSerializer(SerializerProtocol):
def loads_typed(self, data: tuple[str, bytes]) -> Any:
return data[1]
def dumps_typed(self, obj: Any) -> tuple[str, bytes]:
return "type", obj
class MemorySaverAssertImmutable(InMemorySaver):
storage_for_copies: defaultdict[str, dict[str, dict[str, Checkpoint]]]
def __init__(
self,
*,
serde: Optional[SerializerProtocol] = None,
put_sleep: Optional[float] = None,
) -> None:
_, filename = tempfile.mkstemp()
super().__init__(
serde=serde, factory=partial(PersistentDict, filename=filename)
)
self.storage_for_copies = defaultdict(lambda: defaultdict(dict))
self.put_sleep = put_sleep
self.stack.callback(os.remove, filename)
def put(
self,
config: dict,
checkpoint: Checkpoint,
metadata: CheckpointMetadata,
new_versions: ChannelVersions,
) -> None:
if self.put_sleep:
import time
time.sleep(self.put_sleep)
# assert checkpoint hasn't been modified since last written
thread_id = config["configurable"]["thread_id"]
checkpoint_ns = config["configurable"]["checkpoint_ns"]
if saved := super().get(config):
assert (
self.serde.loads_typed(
self.storage_for_copies[thread_id][checkpoint_ns][saved["id"]]
)
== saved
), config["configurable"]["checkpoint_ns"]
self.storage_for_copies[thread_id][checkpoint_ns][checkpoint["id"]] = (
self.serde.dumps_typed(checkpoint)
)
# call super to write checkpoint
return super().put(config, checkpoint, metadata, new_versions)
class MemorySaverNoPending(InMemorySaver):
def get_tuple(self, config: RunnableConfig) -> Optional[CheckpointTuple]:
result = super().get_tuple(config)
if result:
return CheckpointTuple(result.config, result.checkpoint, result.metadata)
return result