venv

1 files changed, 79 insertions, 0 deletions

diff --git a/venv/lib/python3.11/site-packages/litestar/utils/sync.py b/venv/lib/python3.11/site-packages/litestar/utils/sync.py
new file mode 100644
index 0000000..02acabf
--- /dev/null
+++ b/venv/lib/python3.11/site-packages/litestar/utils/sync.py
@@ -0,0 +1,79 @@
+from __future__ import annotations
+
+from typing import (
+    AsyncGenerator,
+    Awaitable,
+    Callable,
+    Generic,
+    Iterable,
+    Iterator,
+    TypeVar,
+)
+
+from typing_extensions import ParamSpec
+
+from litestar.concurrency import sync_to_thread
+from litestar.utils.predicates import is_async_callable
+
+__all__ = ("ensure_async_callable", "AsyncIteratorWrapper", "AsyncCallable", "is_async_callable")
+
+
+P = ParamSpec("P")
+T = TypeVar("T")
+
+
+def ensure_async_callable(fn: Callable[P, T]) -> Callable[P, Awaitable[T]]:
+    """Ensure that ``fn`` is an asynchronous callable.
+    If it is an asynchronous, return the original object, else wrap it in an
+    ``AsyncCallable``
+    """
+    if is_async_callable(fn):
+        return fn
+    return AsyncCallable(fn)  # pyright: ignore
+
+
+class AsyncCallable:
+    """Wrap a given callable to be called in a thread pool using
+    ``anyio.to_thread.run_sync``, keeping a reference to the original callable as
+    :attr:`func`
+    """
+
+    def __init__(self, fn: Callable[P, T]) -> None:  # pyright: ignore
+        self.func = fn
+
+    def __call__(self, *args: P.args, **kwargs: P.kwargs) -> Awaitable[T]:  # pyright: ignore
+        return sync_to_thread(self.func, *args, **kwargs)  # pyright: ignore
+
+
+class AsyncIteratorWrapper(Generic[T]):
+    """Asynchronous generator, wrapping an iterable or iterator."""
+
+    __slots__ = ("iterator", "generator")
+
+    def __init__(self, iterator: Iterator[T] | Iterable[T]) -> None:
+        """Take a sync iterator or iterable and yields values from it asynchronously.
+
+        Args:
+            iterator: A sync iterator or iterable.
+        """
+        self.iterator = iterator if isinstance(iterator, Iterator) else iter(iterator)
+        self.generator = self._async_generator()
+
+    def _call_next(self) -> T:
+        try:
+            return next(self.iterator)
+        except StopIteration as e:
+            raise ValueError from e
+
+    async def _async_generator(self) -> AsyncGenerator[T, None]:
+        while True:
+            try:
+                yield await sync_to_thread(self._call_next)
+            except ValueError:
+                return
+
+    def __aiter__(self) -> AsyncIteratorWrapper[T]:
+        return self
+
+    async def __anext__(self) -> T:
+        return await self.generator.__anext__()