util.py•2.12 kB
"""辅助函数，主要与模板模式有关"""
import inspect
from typing import Union, Type
from typing import List, Dict, Any
JsonExportable = Union[int, float, bool, str, List["JsonExportable"], Dict[str, "JsonExportable"]]
def provide_ctor_defaults(cls: Type) -> Dict[str, Any]:
"""为构造函数提供默认值，以绕开构造函数的参数限制"""
signature = inspect.signature(cls.__init__)
provided_defaults: Dict[str, Any] = {}
for name, param in signature.parameters.items():
if name == 'self': continue
if param.default is not inspect.Parameter.empty: continue
if param.annotation is int or param.annotation is float:
provided_defaults[name] = 0
elif param.annotation is str:
provided_defaults[name] = ""
elif param.annotation is bool:
provided_defaults[name] = False
else:
raise ValueError(f"Unsupported parameter type: {param.annotation}")
return provided_defaults
def assign_attr_with_json(obj: object, attrs: List[str], json_data: Dict[str, Any]):
"""根据json数据赋值给指定的对象属性
若有复杂类型，则尝试调用其`import_json`方法进行构造
"""
type_hints: Dict[str, Type] = {}
for cls in obj.__class__.__mro__:
if '__annotations__' in cls.__dict__:
type_hints.update(cls.__annotations__)
for attr in attrs:
if hasattr(type_hints[attr], 'import_json'):
obj.__setattr__(attr, type_hints[attr].import_json(json_data[attr]))
else:
obj.__setattr__(attr, type_hints[attr](json_data[attr]))
def export_attr_to_json(obj: object, attrs: List[str]) -> Dict[str, JsonExportable]:
"""将对象属性导出为json数据
若有复杂类型，则尝试调用其`export_json`方法进行导出
"""
json_data: Dict[str, Any] = {}
for attr in attrs:
if hasattr(getattr(obj, attr), 'export_json'):
json_data[attr] = getattr(obj, attr).export_json()
else:
json_data[attr] = getattr(obj, attr)
return json_data