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This will help you get started with local filesystem key-value stores. For detailed documentation of all LocalFileStore features and configurations head to the API reference.

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Overview

The LocalFileStore is a persistent implementation of ByteStore that stores everything in a folder of your choosing. It’s useful if you’re using a single machine and are tolerant of files being added or deleted.

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Integration details

ClassPackageLocalJS supportDownloadsVersion
LocalFileStorelangchain✅✅PyPI - DownloadsPyPI - Version

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Installation

The LangChain LocalFileStore integration lives in the langchain package: 
pip install -qU langchain-classic

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Instantiation

Now we can instantiate our byte store: 
from pathlib import Path

from langchain_classic.storage import LocalFileStore

root_path = Path.cwd() / "data"  # can also be a path set by a string

kv_store = LocalFileStore(root_path)

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Usage

You can set data under keys like this using the mset method: 
kv_store.mset(
    [
        ["key1", b"value1"],
        ["key2", b"value2"],
    ]
)

kv_store.mget(
    [
        "key1",
        "key2",
    ]
)

[b'value1', b'value2']
You can see the created files in your data folder: 
!ls {root_path}

key1 key2
And you can delete data using the mdelete method: 
kv_store.mdelete(
    [
        "key1",
        "key2",
    ]
)

kv_store.mget(
    [
        "key1",
        "key2",
    ]
)

[None, None]

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API reference

For detailed documentation of all LocalFileStore features and configurations, head to the API reference
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