Files
langgraph/libs/checkpoint-sqlite/README.md
T
b37f78942d checkpoint-postgres: new library for postgres checkpointer implementation (#1236)
* checkpoint-postgres: new library for postgres checkpointer implementation

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Co-authored-by: Nuno Campos <nuno@langchain.dev>
2024-08-06 22:37:06 -04:00

2.2 KiB

LangGraph SQLite Checkpoint

Implementation of LangGraph CheckpointSaver that uses SQLite DB (both sync and async, via aiosqlite)

Usage

from langgraph.checkpoint.sqlite import SqliteSaver

write_config = {"configurable": {"thread_id": "1", "checkpoint_ns": ""}}
read_config = {"configurable": {"thread_id": "1"}}

with SqliteSaver.from_conn_string(":memory:") as checkpointer:
    checkpoint = {
        "v": 1,
        "ts": "2024-07-31T20:14:19.804150+00:00",
        "id": "1ef4f797-8335-6428-8001-8a1503f9b875",
        "channel_values": {
            "my_key": "meow",
            "node": "node"
        },
        "channel_versions": {
            "__start__": 2,
            "my_key": 3,
            "start:node": 3,
            "node": 3
        },
        "versions_seen": {
            "__input__": {},
            "__start__": {
                "__start__": 1
            },
            "node": {
                "start:node": 2
            }
        },
        "pending_sends": [],
        "current_tasks": {}
    }

    # store checkpoint
    checkpointer.put(write_config, checkpoint, {}, {})

    # load checkpoint
    checkpointer.get(read_config)

    # list checkpoints
    list(checkpointer.list(read_config))

Async

from langgraph.checkpoint.sqlite.aio import AsyncSqliteSaver

async with AsyncSqliteSaver.from_conn_string(":memory:") as checkpointer:
    checkpoint = {
        "v": 1,
        "ts": "2024-07-31T20:14:19.804150+00:00",
        "id": "1ef4f797-8335-6428-8001-8a1503f9b875",
        "channel_values": {
            "my_key": "meow",
            "node": "node"
        },
        "channel_versions": {
            "__start__": 2,
            "my_key": 3,
            "start:node": 3,
            "node": 3
        },
        "versions_seen": {
            "__input__": {},
            "__start__": {
                "__start__": 1
            },
            "node": {
                "start:node": 2
            }
        },
        "pending_sends": [],
        "current_tasks": {}
    }

    # store checkpoint
    await checkpointer.aput(write_config, checkpoint, {}, {})

    # load checkpoint
    await checkpointer.aget(read_config)

    # list checkpoints
    [c async for c in checkpointer.alist(read_config)]