Python native key/value storage

python_kv_store.py

"""
This file contains helper functions for the built-in 
python (key, value) storage
"""

import dbm
from secrets import token_urlsafe
from logging import getLogger
from typing import Union, Tuple

logger = getLogger(__name__)

def store(value: Union[str, bytes], length: int, key: str = None) -> str:
    """
    Method stores the value using the provided key, or with a generated one.
    Arguement(s):
    - key:       <str>                (optional) identifying key for the value
    - length:    <int>                length of the generated key
    - value:     <Union[str, bytes]>  value to store

    Returns
    - key:       <str>                the key used
    """
    try:  # To store value to kv-storage
        if value not str or value not bytes:  # Then it's invalid
            raise ValueError
        if key is None:  # Then generate it
            key = token_urlsafe(length or None)

        # Default
        with dbm.open('database/storage') as storage:
            storage[key] = value
    except ValueError:
        logger.exception('Value has to be str or bytes!')


def get(key: str) -> Tuple[str, Union[str, bytes]]:
    """
    Method retrieves value by key.
    Arguement(s):
    - key:       (str)               key to retrieve value with

    Returns:
    - Tuple[str, Union[str, bytes]]  returns a key,value pair as a tuple
    """
    try:  # To store value to kv-storage
        with dbm.open('database/storage') as storage:
            storage[key] = value
    except KeyError:
        msg: str = f"Invalid key used: '{key}'"
        logger.exception(msg)