Update 2025-04-13_16:26:04

venv/lib/python3.11/site-packages/starlette/_exception_handler.py

@@ -0,0 +1,65 @@
+from __future__ import annotations
+
+import typing
+
+from starlette._utils import is_async_callable
+from starlette.concurrency import run_in_threadpool
+from starlette.exceptions import HTTPException
+from starlette.requests import Request
+from starlette.types import ASGIApp, ExceptionHandler, Message, Receive, Scope, Send
+from starlette.websockets import WebSocket
+
+ExceptionHandlers = dict[typing.Any, ExceptionHandler]
+StatusHandlers = dict[int, ExceptionHandler]
+
+
+def _lookup_exception_handler(exc_handlers: ExceptionHandlers, exc: Exception) -> ExceptionHandler | None:
+    for cls in type(exc).__mro__:
+        if cls in exc_handlers:
+            return exc_handlers[cls]
+    return None
+
+
+def wrap_app_handling_exceptions(app: ASGIApp, conn: Request | WebSocket) -> ASGIApp:
+    exception_handlers: ExceptionHandlers
+    status_handlers: StatusHandlers
+    try:
+        exception_handlers, status_handlers = conn.scope["starlette.exception_handlers"]
+    except KeyError:
+        exception_handlers, status_handlers = {}, {}
+
+    async def wrapped_app(scope: Scope, receive: Receive, send: Send) -> None:
+        response_started = False
+
+        async def sender(message: Message) -> None:
+            nonlocal response_started
+
+            if message["type"] == "http.response.start":
+                response_started = True
+            await send(message)
+
+        try:
+            await app(scope, receive, sender)
+        except Exception as exc:
+            handler = None
+
+            if isinstance(exc, HTTPException):
+                handler = status_handlers.get(exc.status_code)
+
+            if handler is None:
+                handler = _lookup_exception_handler(exception_handlers, exc)
+
+            if handler is None:
+                raise exc
+
+            if response_started:
+                raise RuntimeError("Caught handled exception, but response already started.") from exc
+
+            if is_async_callable(handler):
+                response = await handler(conn, exc)
+            else:
+                response = await run_in_threadpool(handler, conn, exc)  # type: ignore
+            if response is not None:
+                await response(scope, receive, sender)
+
+    return wrapped_app