49 lines
1.2 KiB
Python

"""
This module provides type to annotate the content of web.Response returned by
the HTTP handlers.
The type are: r100, r101, ..., r599
Example:
class PetCollectionView(PydanticView):
async def get(self) -> Union[r200[List[Pet]], r404]:
...
"""
from functools import lru_cache
from types import new_class
from typing import Protocol, TypeVar
RespContents = TypeVar("RespContents", covariant=True)
_status_code = frozenset(f"r{code}" for code in range(100, 600))
@lru_cache(maxsize=len(_status_code))
def _make_status_code_type(status_code):
if status_code in _status_code:
return new_class(status_code, (Protocol[RespContents],))
return None
def is_status_code_type(obj) -> bool:
"""
Return True if obj is a status code type such as _200 or _404.
"""
name = getattr(obj, "__name__", None)
if name not in _status_code:
return False
return obj is _make_status_code_type(name)
def __getattr__(name):
if (status_code_type := _make_status_code_type(name)) is None:
raise AttributeError(f"module {__name__!r} has no attribute {name!r}")
return status_code_type
__all__ = list(_status_code)
__all__.append("is_status_code_type")