docker-tidy/dockertidy/utils.py

49 lines
1.0 KiB
Python

#!/usr/bin/env python3
"""Global utility methods and classes."""
def strtobool(value):
"""Convert a string representation of truth to true or false."""
_map = {
"y": True,
"yes": True,
"t": True,
"true": True,
"on": True,
"1": True,
"n": False,
"no": False,
"f": False,
"false": False,
"off": False,
"0": False,
}
try:
return _map[str(value).lower()]
except KeyError as err:
raise ValueError(f'"{value}" is not a valid bool value') from err
def to_bool(string):
return bool(strtobool(str(string)))
def dict_intersect(d1, d2):
return {
k: dict_intersect(d1[k], d2[k]) if isinstance(d1[k], dict) else d1[k]
for k in d1.keys() & d2.keys()
}
class Singleton(type):
"""Singleton metaclass."""
_instances = {}
def __call__(cls, *args, **kwargs):
if cls not in cls._instances:
cls._instances[cls] = super().__call__(*args, **kwargs)
return cls._instances[cls]