# Copyright (c) 2016 Cyso < development [at] cyso . com >
#
# This file is part of omniconf, a.k.a. python-omniconf .
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 3.0 of the License, or (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library. If not, see
# <http://www.gnu.org/licenses/>.
from collections import OrderedDict
from typing import Any, Dict, List, Optional, Type, Union
from omniconf.types import CallableType
class Setting:
"""
A :class:`.Setting` is registered under a specific key and with a specific
type (:class:`str`, :class:`dict`, :class:`list`, etc). A default may also
be specified, which allows a config to be returned without a value being
specifically defined (also see :class:`.ConfigRegistry`). A
:class:`.Setting` may be marked as required, which will cause an exception
to be thrown when no value is found when autoconfiguring. A help message
may be specified for documentation purposes.
"""
def __init__(
self,
key: str,
_type: CallableType = str,
required: bool = False,
default: Optional[Any] = None,
help: Optional[str] = None,
) -> None:
self.key = key
self.type = _type
self.required = required
self.default = default
self.help = help
class SettingRegistry:
"""
A registry of defined :class:`Setting` objects.
"""
def __init__(self) -> None:
self.registry: Dict[str, Setting] = OrderedDict()
def _key(self, setting: Union[str, Setting]) -> str:
if isinstance(setting, str):
return setting
return setting.key
def clear(self) -> None:
self.registry = OrderedDict()
def add(self, setting: Setting) -> Setting:
"""
Register a Setting.
"""
self.registry[setting.key] = setting
return setting
def has(self, key: str) -> bool:
"""
Check if a Setting has been registered under the specified key.
"""
return key in self.registry
def get(self, key: str) -> Setting:
"""
Retrieves the Setting for the given key.
"""
return self.registry[key]
def keys(self) -> List[str]:
"""
Returns the registered keys.
"""
return list(self.registry.keys())
def list(self) -> List[Setting]:
"""
Returns the configured Settings as a list.
"""
return list(self.registry.values())
def remove(self, setting: Union[str, Setting]) -> None:
"""
Removes the Setting with the given key.
"""
del self.registry[self._key(setting)]
DEFAULT_REGISTRY = SettingRegistry()
"""
Global :class:`.SettingRegistry` which will be used when no specific
:class:`.SettingRegistry` is defined.
"""
[docs]
def setting(
key: str,
_type: CallableType = str,
required: bool = False,
default: Optional[Any] = None,
help: Optional[str] = None,
registry: Optional[SettingRegistry] = None,
type_hint: Optional[Type[Any]] = None,
) -> Setting:
"""
Register a new :class:`.Setting` with the given key.
"""
if not registry:
registry = DEFAULT_REGISTRY
return registry.add(Setting(key, _type, required, default, help))