langchain/libs/experimental/langchain_experimental/rl_chain/vw_logger.py

from os import PathLike
from pathlib import Path
from typing import Optional, Union


class VwLogger:
    def __init__(self, path: Optional[Union[str, PathLike]]):
        self.path = Path(path) if path else None
        if self.path:
            self.path.parent.mkdir(parents=True, exist_ok=True)

    def log(self, vw_ex: str) -> None:
        if self.path:
            with open(self.path, "a") as f:
                f.write(f"{vw_ex}\n\n")

    def logging_enabled(self) -> bool:
        return bool(self.path)