config.py

from pathlib import Path
import os
import yaml
def load_global_config(cfg_path: str | None = None) -> dict:
    """
    Load global_config.yml.
    Priority:
      1) explicit cfg_path
      2) env GLOBAL_CONFIG_YML
      3) ./global_config.yml (project root = current working dir)
    """
    if cfg_path is None:
        cfg_path = os.environ.get("GLOBAL_CONFIG_YML", "global_config.yml")

    cfg_file = Path(cfg_path)
    if not cfg_file.exists():
        raise FileNotFoundError(f"global config not found: {cfg_file.resolve()}")

    with cfg_file.open("r", encoding="utf-8") as f:
        return yaml.safe_load(f) or {}


# from __future__ import annotations
from functools import reduce
from operator import getitem
from pathlib import Path
import os
from typing import Any, Callable, Iterable, Sequence


def deep_get(d: Any, keys: Sequence[Any], default: Any = None) -> Any:
    """Safely get nested value: deep_get(cfg, ['a','b','c'])"""
    try:
        return reduce(getitem, keys, d)
    except (KeyError, TypeError):
        return default


def coalesce(*vals: Any) -> Any:
    """Return the first non-empty (not None and not '') value."""
    for v in vals:
        if v is not None and v != "":
            return v
    return None


def cfg_value(
    cfg: dict,
    *keypaths: Sequence[Any],
    default: Any = None,
    required: bool = False,
    cast: Callable[[Any], Any] | None = None,
    post: Callable[[Any], Any] | None = None,
) -> Any:
    """
    Generic config getter with priority:
      cfg_value(cfg, ['a','b'], ['x','y'], default=..., cast=int, ...)
    - tries keypaths in order
    - falls back to default
    - optional required, cast, post
    """
    val = coalesce(*(deep_get(cfg, kp, None) for kp in keypaths), default)

    if required and (val is None or val == ""):
        raise KeyError(f"Missing required config value for keypaths={keypaths}")

    if cast is not None and val is not None:
        val = cast(val)

    if post is not None and val is not None:
        val = post(val)

    return val

from pathlib import Path
import os

def normalize_path(p):
    return str(Path(os.path.expandvars(os.path.expanduser(p))))

def cfg_get(cfg, *keypaths, default=None, required=False, cast=None):
    return cfg_value(
        cfg,
        *keypaths,
        default=default,
        required=required,
        cast=cast,
        post=normalize_path if cast is str or default is not None else None,
    )