Add async support for temporary file handling. Closes #344

docs/index.rst

@@ -20,6 +20,7 @@ The manual
    subprocesses
    subinterpreters
    fileio
+   tempfile
    signals
    testing
    api

docs/tempfile.rst

@@ -0,0 +1,119 @@
+Asynchronous Temporary File and Directory
+=========================================
+
+.. py:currentmodule:: anyio
+
+This module provides asynchronous wrappers for handling temporary files and directories
+using the :mod:`tempfile` module. The asynchronous methods execute blocking operations in worker threads.
+
+Temporary File
+--------------
+
+:class:`TemporaryFile` creates a temporary file that is automatically deleted upon closure.
+
+**Example:**
+
+.. code-block:: python
+
+    from anyio import TemporaryFile, run
+
+    async def main():
+        async with TemporaryFile(mode="w+") as f:
+            await f.write("Temporary file content")
+            await f.seek(0)
+            print(await f.read())  # Output: Temporary file content
+
+    run(main)
+
+Named Temporary File
+--------------------
+
+:class:`NamedTemporaryFile` works similarly to :class:`TemporaryFile`, but the file has a visible name in the filesystem.
+
+**Example:**
+
+.. code-block:: python
+
+    from anyio import NamedTemporaryFile, run
+
+    async def main():
+        async with NamedTemporaryFile(mode="w+", delete=True) as f:
+            print(f"Temporary file name: {f.name}")
+            await f.write("Named temp file content")
+            await f.seek(0)
+            print(await f.read())
+
+    run(main)
+
+Spooled Temporary File
+----------------------
+
+:class:`SpooledTemporaryFile` is useful when temporary data is small and should be kept in memory rather than written to disk.
+
+**Example:**
+
+.. code-block:: python
+
+    from anyio import SpooledTemporaryFile, run
+
+    async def main():
+        async with SpooledTemporaryFile(max_size=1024, mode="w+") as f:
+            await f.write("Spooled temp file content")
+            await f.seek(0)
+            print(await f.read())
+
+    run(main)
+
+Temporary Directory
+-------------------
+
+The :class:`TemporaryDirectory` provides an asynchronous way to create temporary directories.
+
+**Example:**
+
+.. code-block:: python
+
+    from anyio import TemporaryDirectory, run
+
+    async def main():
+        async with TemporaryDirectory() as temp_dir:
+            print(f"Temporary directory path: {temp_dir}")
+
+    run(main)
+
+Low-Level Temporary File and Directory Creation
+-----------------------------------------------
+
+For more control, the module provides lower-level functions:
+
+- :func:`mkstemp` - Creates a temporary file and returns a tuple of file descriptor and path.
+- :func:`mkdtemp` - Creates a temporary directory and returns the directory path.
+- :func:`gettempdir` - Returns the path of the default temporary directory.
+- :func:`gettempdirb` - Returns the path of the default temporary directory in bytes.
+
+**Example:**
+
+.. code-block:: python
+
+    from anyio import mkstemp, mkdtemp, gettempdir, run
+    import os
+
+    async def main():
+        fd, path = await mkstemp(suffix=".txt", prefix="mkstemp_", text=True)
+        print(f"Created temp file: {path}")
+
+        temp_dir = await mkdtemp(prefix="mkdtemp_")
+        print(f"Created temp dir: {temp_dir}")
+
+        print(f"Default temp dir: {await gettempdir()}")
+
+        os.remove(path)
+
+    run(main)
+
+.. note::
+    Using these functions requires manual cleanup of the created files and directories.
+
+.. seealso::
+
+    - Python Standard Library: :mod:`tempfile` (`official documentation <https://docs.python.org/3/library/tempfile.html>`_)

pyproject.toml

@@ -90,6 +90,9 @@ extend-select = [
 [tool.ruff.lint.isort]
 "required-imports" = ["from __future__ import annotations"]
 
+[tool.ruff.lint.per-file-ignores]
+"tests/test_tempfile.py" = ["ASYNC230"]
+
 [tool.mypy]
 python_version = "3.13"
 strict = true

src/anyio/__init__.py

@@ -61,6 +61,14 @@
 from ._core._tasks import current_effective_deadline as current_effective_deadline
 from ._core._tasks import fail_after as fail_after
 from ._core._tasks import move_on_after as move_on_after
+from ._core._tempfile import NamedTemporaryFile as NamedTemporaryFile
+from ._core._tempfile import SpooledTemporaryFile as SpooledTemporaryFile
+from ._core._tempfile import TemporaryDirectory as TemporaryDirectory
+from ._core._tempfile import TemporaryFile as TemporaryFile
+from ._core._tempfile import gettempdir as gettempdir
+from ._core._tempfile import gettempdirb as gettempdirb
+from ._core._tempfile import mkdtemp as mkdtemp
+from ._core._tempfile import mkstemp as mkstemp
 from ._core._testing import TaskInfo as TaskInfo
 from ._core._testing import get_current_task as get_current_task
 from ._core._testing import get_running_tasks as get_running_tasks