| | import os |
| | import re |
| | import time |
| | from pathlib import Path |
| | from typing import Iterator, List, Optional, Sequence, Tuple, Union |
| |
|
| | from langchain_core.stores import ByteStore |
| |
|
| | from langchain.storage.exceptions import InvalidKeyException |
| |
|
| |
|
| | class LocalFileStore(ByteStore): |
| | """BaseStore interface that works on the local file system. |
| | |
| | Examples: |
| | Create a LocalFileStore instance and perform operations on it: |
| | |
| | .. code-block:: python |
| | |
| | from langchain.storage import LocalFileStore |
| | |
| | # Instantiate the LocalFileStore with the root path |
| | file_store = LocalFileStore("/path/to/root") |
| | |
| | # Set values for keys |
| | file_store.mset([("key1", b"value1"), ("key2", b"value2")]) |
| | |
| | # Get values for keys |
| | values = file_store.mget(["key1", "key2"]) # Returns [b"value1", b"value2"] |
| | |
| | # Delete keys |
| | file_store.mdelete(["key1"]) |
| | |
| | # Iterate over keys |
| | for key in file_store.yield_keys(): |
| | print(key) # noqa: T201 |
| | |
| | """ |
| |
|
| | def __init__( |
| | self, |
| | root_path: Union[str, Path], |
| | *, |
| | chmod_file: Optional[int] = None, |
| | chmod_dir: Optional[int] = None, |
| | update_atime: bool = False, |
| | ) -> None: |
| | """Implement the BaseStore interface for the local file system. |
| | |
| | Args: |
| | root_path (Union[str, Path]): The root path of the file store. All keys are |
| | interpreted as paths relative to this root. |
| | chmod_file: (optional, defaults to `None`) If specified, sets permissions |
| | for newly created files, overriding the current `umask` if needed. |
| | chmod_dir: (optional, defaults to `None`) If specified, sets permissions |
| | for newly created dirs, overriding the current `umask` if needed. |
| | update_atime: (optional, defaults to `False`) If `True`, updates the |
| | filesystem access time (but not the modified time) when a file is read. |
| | This allows MRU/LRU cache policies to be implemented for filesystems |
| | where access time updates are disabled. |
| | """ |
| | self.root_path = Path(root_path).absolute() |
| | self.chmod_file = chmod_file |
| | self.chmod_dir = chmod_dir |
| | self.update_atime = update_atime |
| |
|
| | def _get_full_path(self, key: str) -> Path: |
| | """Get the full path for a given key relative to the root path. |
| | |
| | Args: |
| | key (str): The key relative to the root path. |
| | |
| | Returns: |
| | Path: The full path for the given key. |
| | """ |
| | if not re.match(r"^[a-zA-Z0-9_.\-/]+$", key): |
| | raise InvalidKeyException(f"Invalid characters in key: {key}") |
| | full_path = os.path.abspath(self.root_path / key) |
| | common_path = os.path.commonpath([str(self.root_path), full_path]) |
| | if common_path != str(self.root_path): |
| | raise InvalidKeyException( |
| | f"Invalid key: {key}. Key should be relative to the full path." |
| | f"{self.root_path} vs. {common_path} and full path of {full_path}" |
| | ) |
| |
|
| | return Path(full_path) |
| |
|
| | def _mkdir_for_store(self, dir: Path) -> None: |
| | """Makes a store directory path (including parents) with specified permissions |
| | |
| | This is needed because `Path.mkdir()` is restricted by the current `umask`, |
| | whereas the explicit `os.chmod()` used here is not. |
| | |
| | Args: |
| | dir: (Path) The store directory to make |
| | |
| | Returns: |
| | None |
| | """ |
| | if not dir.exists(): |
| | self._mkdir_for_store(dir.parent) |
| | dir.mkdir(exist_ok=True) |
| | if self.chmod_dir is not None: |
| | os.chmod(dir, self.chmod_dir) |
| |
|
| | def mget(self, keys: Sequence[str]) -> List[Optional[bytes]]: |
| | """Get the values associated with the given keys. |
| | |
| | Args: |
| | keys: A sequence of keys. |
| | |
| | Returns: |
| | A sequence of optional values associated with the keys. |
| | If a key is not found, the corresponding value will be None. |
| | """ |
| | values: List[Optional[bytes]] = [] |
| | for key in keys: |
| | full_path = self._get_full_path(key) |
| | if full_path.exists(): |
| | value = full_path.read_bytes() |
| | values.append(value) |
| | if self.update_atime: |
| | |
| | os.utime(full_path, (time.time(), os.stat(full_path).st_mtime)) |
| | else: |
| | values.append(None) |
| | return values |
| |
|
| | def mset(self, key_value_pairs: Sequence[Tuple[str, bytes]]) -> None: |
| | """Set the values for the given keys. |
| | |
| | Args: |
| | key_value_pairs: A sequence of key-value pairs. |
| | |
| | Returns: |
| | None |
| | """ |
| | for key, value in key_value_pairs: |
| | full_path = self._get_full_path(key) |
| | self._mkdir_for_store(full_path.parent) |
| | full_path.write_bytes(value) |
| | if self.chmod_file is not None: |
| | os.chmod(full_path, self.chmod_file) |
| |
|
| | def mdelete(self, keys: Sequence[str]) -> None: |
| | """Delete the given keys and their associated values. |
| | |
| | Args: |
| | keys (Sequence[str]): A sequence of keys to delete. |
| | |
| | Returns: |
| | None |
| | """ |
| | for key in keys: |
| | full_path = self._get_full_path(key) |
| | if full_path.exists(): |
| | full_path.unlink() |
| |
|
| | def yield_keys(self, prefix: Optional[str] = None) -> Iterator[str]: |
| | """Get an iterator over keys that match the given prefix. |
| | |
| | Args: |
| | prefix (Optional[str]): The prefix to match. |
| | |
| | Returns: |
| | Iterator[str]: An iterator over keys that match the given prefix. |
| | """ |
| | prefix_path = self._get_full_path(prefix) if prefix else self.root_path |
| | for file in prefix_path.rglob("*"): |
| | if file.is_file(): |
| | relative_path = file.relative_to(self.root_path) |
| | yield str(relative_path) |
| |
|
