add

2026-10-15 20:36:59 +08:00
commit 6bf949949c
7923 changed files with 1369582 additions and 0 deletions
@@ -0,0 +1,152 @@
+from __future__ import annotations
+
+import functools
+import re
+import sys
+from collections.abc import AsyncGenerator, Awaitable, Callable, Generator
+from contextlib import AbstractAsyncContextManager, asynccontextmanager
+from dataclasses import dataclass
+from ipaddress import AddressValueError, IPv6Address
+from typing import Any, Generic, Protocol, TypeVar, overload
+
+import anyio.abc
+
+from starlette.types import Scope
+
+if sys.version_info >= (3, 13):  # pragma: no cover
+    from inspect import iscoroutinefunction
+    from typing import TypeIs
+else:  # pragma: no cover
+    from asyncio import iscoroutinefunction
+
+    from typing_extensions import TypeIs
+
+
+T = TypeVar("T")
+AwaitableCallable = Callable[..., Awaitable[T]]
+
+# Reject characters that could make a Host header change the URL path or authority.
+_HOST_RE = re.compile(
+    r"^(?P<host>[a-z0-9._~%!$&'()*+,;=-]+|\[(?:(?P<ipv6>[a-f0-9]*:[a-f0-9.:]+)|"
+    r"(?-i:v)[a-f0-9]+\.[a-z0-9._~!$&'()*+,;=:-]+)\])(?::(?P<port>[0-9]+))?$",
+    re.IGNORECASE,
+)
+
+
+@dataclass(frozen=True, slots=True)
+class ParsedHost:
+    host: str
+    port: str | None
+
+    @property
+    def authority(self) -> str:
+        return self.host if self.port is None else f"{self.host}:{self.port}"
+
+    @property
+    def is_valid_port(self) -> bool:
+        if self.port is None:
+            return True
+        port = self.port.lstrip("0")
+        return len(port) <= 5 and int(port or "0") <= 65535
+
+
+@overload
+def is_async_callable(obj: AwaitableCallable[T]) -> TypeIs[AwaitableCallable[T]]: ...
+
+
+@overload
+def is_async_callable(obj: Any) -> TypeIs[AwaitableCallable[Any]]: ...
+
+
+def is_async_callable(obj: Any) -> Any:
+    while isinstance(obj, functools.partial):
+        obj = obj.func
+
+    return iscoroutinefunction(obj) or (callable(obj) and iscoroutinefunction(obj.__call__))
+
+
+T_co = TypeVar("T_co", covariant=True)
+
+
+class AwaitableOrContextManager(
+    Awaitable[T_co], AbstractAsyncContextManager[T_co], Protocol[T_co]
+): ...  # pragma: no branch
+
+
+class SupportsAsyncClose(Protocol):
+    async def close(self) -> None: ...  # pragma: no cover
+
+
+SupportsAsyncCloseType = TypeVar("SupportsAsyncCloseType", bound=SupportsAsyncClose, covariant=False)
+
+
+class AwaitableOrContextManagerWrapper(Generic[SupportsAsyncCloseType]):
+    __slots__ = ("aw", "entered")
+
+    def __init__(self, aw: Awaitable[SupportsAsyncCloseType]) -> None:
+        self.aw = aw
+
+    def __await__(self) -> Generator[Any, None, SupportsAsyncCloseType]:
+        return self.aw.__await__()
+
+    async def __aenter__(self) -> SupportsAsyncCloseType:
+        self.entered = await self.aw
+        return self.entered
+
+    async def __aexit__(self, *args: Any) -> None | bool:
+        await self.entered.close()
+        return None
+
+
+@asynccontextmanager
+async def create_collapsing_task_group() -> AsyncGenerator[anyio.abc.TaskGroup, None]:
+    try:
+        async with anyio.create_task_group() as tg:
+            yield tg
+    except BaseExceptionGroup as excs:
+        if len(excs.exceptions) != 1:
+            raise
+
+        exc = excs.exceptions[0]
+        context = None if exc.__suppress_context__ else exc.__context__
+        raise exc from exc.__cause__ or context
+
+
+def parse_host_header(host_header: str | None) -> ParsedHost | None:
+    """Parse `host_header` into its host and port components.
+
+    The host preserves brackets around IP literals. Invalid headers produce `None`.
+    """
+    if host_header is None:
+        return None
+
+    match = _HOST_RE.fullmatch(host_header)
+    if match is None:
+        return None
+
+    ipv6 = match["ipv6"]
+    if ipv6 is not None:
+        try:
+            IPv6Address(ipv6)
+        except AddressValueError:
+            return None
+
+    return ParsedHost(match["host"], match["port"])
+
+
+def get_route_path(scope: Scope) -> str:
+    path: str = scope["path"]
+    root_path = scope.get("root_path", "")
+    if not root_path:
+        return path
+
+    if not path.startswith(root_path):
+        return path
+
+    if path == root_path:
+        return ""
+
+    if path[len(root_path)] == "/":
+        return path[len(root_path) :]
+
+    return path