better async webdav implementation

api/advent22_api/core/helpers.py

@@ -84,10 +84,15 @@ async def list_images_auto() -> list[str]:
     Finde alle Bilddateien im "automatisch"-Verzeichnis
     """
 
-    return await WebDAV.list_files(
-        directory="/images_auto",
+    __DIR = "/images_auto"
+
+    return [
+        f"{__DIR}/{file}"
+        for file in await WebDAV.list_files(
+            directory=__DIR,
             regex=re.compile(r"\.(gif|jpe?g|tiff?|png|bmp)$", flags=re.IGNORECASE),
         )
+    ]
 
 
 async def load_image(file_name: str) -> Image.Image:
@@ -95,7 +100,7 @@ async def load_image(file_name: str) -> Image.Image:
     Versuche, Bild aus Datei zu laden
     """
 
-    if not await WebDAV.file_exists(file_name):
+    if not await WebDAV.exists(file_name):
         raise RuntimeError(f"DAV-File {file_name} does not exist!")
 
     return Image.open(BytesIO(await WebDAV.read_bytes(file_name)))

api/advent22_api/core/settings.py

@@ -20,6 +20,7 @@ class DavSettings(BaseModel):
     password: str = "password"
 
     cache_ttl: int = 60 * 30
+    cache_size: int = 1024
     config_filename: str = "config.toml"
 
     @property

api/advent22_api/core/webdav.py

@@ -1,16 +1,44 @@
-import asyncio
+import functools
+import logging
 import re
 from io import BytesIO
 
-from cache import AsyncTTL
-from cache.key import KEY
+import requests
+from asyncify import asyncify
+from cachetools import TTLCache, cachedmethod
+from cachetools.keys import hashkey
 from webdav3.client import Client as WebDAVclient
 
 from .settings import SETTINGS
 
+_logger = logging.getLogger(__name__)
+
+
+def davkey(name, _, *args, **kwargs):
+    """Return a cache key for use with cached methods."""
+
+    return hashkey(name, *args, **kwargs)
+
 
 class WebDAV:
-    _webdav_client = WebDAVclient(
+    class __WebDAVclient(WebDAVclient):
+        def execute_request(
+            self,
+            action,
+            path,
+            data=None,
+            headers_ext=None,
+        ) -> requests.Response:
+            res = super().execute_request(action, path, data, headers_ext)
+
+            # the "Content-Length" header can randomly be missing on txt files,
+            # this should fix that (probably serverside bug)
+            if action == "download" and "Content-Length" not in res.headers:
+                res.headers["Content-Length"] = str(len(res.text))
+
+            return res
+
+    _webdav_client = __WebDAVclient(
         {
             "webdav_hostname": SETTINGS.webdav.url,
             "webdav_login": SETTINGS.webdav.username,
@@ -18,55 +46,60 @@ class WebDAV:
         }
     )
 
+    _cache = TTLCache(
+        ttl=SETTINGS.webdav.cache_ttl,
+        maxsize=SETTINGS.webdav.cache_size,
+    )
+
     @classmethod
-    @AsyncTTL(time_to_live=SETTINGS.webdav.cache_ttl, skip_args=1)
-    async def list_files(
+    @asyncify
+    @cachedmethod(
+        cache=lambda cls: cls._cache,
+        key=functools.partial(davkey, "list_files"),
+    )
+    def list_files(
         cls,
         directory: str = "",
         *,
         regex: re.Pattern[str] = re.compile(""),
     ) -> list[str]:
         """
-        Liste aller Dateien im Ordner `directory`, die zur RegEx `regex` passen
+        List files in directory `directory` matching RegEx `regex`
         """
 
-        loop = asyncio.get_running_loop()
-        ls = await loop.run_in_executor(
-            None,
-            cls._webdav_client.list,
-            directory,
-        )
+        _logger.debug(f"list_files {directory!r}")
+        ls = cls._webdav_client.list(directory)
 
-        return [f"{directory}/{path}" for path in ls if regex.search(path)]
+        return [path for path in ls if regex.search(path)]
 
     @classmethod
-    @AsyncTTL(time_to_live=SETTINGS.webdav.cache_ttl, skip_args=1)
-    async def file_exists(cls, path: str) -> bool:
+    @asyncify
+    @cachedmethod(
+        cache=lambda cls: cls._cache,
+        key=functools.partial(davkey, "exists"),
+    )
+    def exists(cls, path: str) -> bool:
         """
-        `True`, wenn an Pfad `path` eine Datei existiert
+        `True` iff there is a WebDAV resource at `path`
         """
 
-        loop = asyncio.get_running_loop()
-        return await loop.run_in_executor(
-            None,
-            cls._webdav_client.check,
-            path,
-        )
+        _logger.debug(f"file_exists {path!r}")
+        return cls._webdav_client.check(path)
 
     @classmethod
-    @(_rb_ttl := AsyncTTL(time_to_live=SETTINGS.webdav.cache_ttl, skip_args=1))
-    async def read_bytes(cls, path: str) -> bytes:
+    @asyncify
+    @cachedmethod(
+        cache=lambda cls: cls._cache,
+        key=functools.partial(davkey, "read_bytes"),
+    )
+    def read_bytes(cls, path: str) -> bytes:
         """
-        Datei aus Pfad `path` als bytes laden
+        Load WebDAV file from `path` as bytes
         """
 
+        _logger.debug(f"read_bytes {path!r}")
         buffer = BytesIO()
-        loop = asyncio.get_running_loop()
-        await loop.run_in_executor(
-            None,
-            cls._webdav_client.resource(path).write_to,
-            buffer,
-        )
+        cls._webdav_client.download_from(buffer, path)
         buffer.seek(0)
 
         return buffer.read()
@@ -74,37 +107,30 @@ class WebDAV:
     @classmethod
     async def read_str(cls, path: str, encoding="utf-8") -> str:
         """
-        Datei aus Pfad `path` als string laden
+        Load WebDAV file from `path` as string
         """
 
+        _logger.debug(f"read_str {path!r}")
         return (await cls.read_bytes(path)).decode(encoding=encoding).strip()
 
     @classmethod
-    async def write_bytes(cls, path: str, buffer: bytes) -> None:
+    @asyncify
+    def write_bytes(cls, path: str, buffer: bytes) -> None:
         """
-        Bytes `buffer` in Datei in Pfad `path` schreiben
+        Write bytes from `buffer` into WebDAV file at `path`
         """
 
-        loop = asyncio.get_running_loop()
-        await loop.run_in_executor(
-            None,
-            cls._webdav_client.resource(path).read_from,
-            buffer,
-        )
+        _logger.debug(f"write_bytes {path!r}")
+        cls._webdav_client.upload_to(buffer, path)
 
-        try:
-            # hack: zugehörigen Cache-Eintrag entfernen
-            # -> AsyncTTL._TTL.__contains__
-            del cls._rb_ttl.ttl[KEY((path,), {})]
-
-        except KeyError:
-            # Cache-Eintrag existierte nicht
-            pass
+        # invalidate cache entry
+        cls._cache.pop(hashkey("read_bytes", path))
 
     @classmethod
     async def write_str(cls, path: str, content: str, encoding="utf-8") -> None:
         """
-        String `content` in Datei in Pfad `path` schreiben
+        Write string from `content` into WebDAV file at `path`
         """
 
+        _logger.debug(f"write_str {path!r}")
         await cls.write_bytes(path, content.encode(encoding=encoding))

api/poetry.lock

@@ -32,13 +32,29 @@ test = ["anyio[trio]", "coverage[toml] (>=4.5)", "hypothesis (>=4.0)", "mock (>=
 trio = ["trio (<0.22)"]
 
 [[package]]
-name = "async-cache"
-version = "1.1.1"
-description = "An asyncio Cache"
+name = "asyncify"
+version = "0.9.2"
+description = "sync 2 async"
 optional = false
-python-versions = ">=3.3"
+python-versions = ">=3.7,<4.0"
 files = [
-    {file = "async-cache-1.1.1.tar.gz", hash = "sha256:81aa9ccd19fb06784aaf30bd5f2043dc0a23fc3e998b93d0c2c17d1af9803393"},
+    {file = "asyncify-0.9.2-py3-none-any.whl", hash = "sha256:ee7efe8ecc11f348d4f25d4d1c5fb2f56a187aaa907aea3608106359728a2cdd"},
+    {file = "asyncify-0.9.2.tar.gz", hash = "sha256:5f06016a5d805354505e98e9c009595cba7905ceb767ed7cd61bf60f2341d896"},
+]
+
+[package.dependencies]
+funkify = ">=0.4.0,<0.5.0"
+xtyping = ">=0.5.0"
+
+[[package]]
+name = "cachetools"
+version = "5.3.2"
+description = "Extensible memoizing collections and decorators"
+optional = false
+python-versions = ">=3.7"
+files = [
+    {file = "cachetools-5.3.2-py3-none-any.whl", hash = "sha256:861f35a13a451f94e301ce2bec7cac63e881232ccce7ed67fab9b5df4d3beaa1"},
+    {file = "cachetools-5.3.2.tar.gz", hash = "sha256:086ee420196f7b2ab9ca2db2520aca326318b68fe5ba8bc4d49cca91add450f2"},
 ]
 
 [[package]]
@@ -197,6 +213,17 @@ mccabe = ">=0.7.0,<0.8.0"
 pycodestyle = ">=2.11.0,<2.12.0"
 pyflakes = ">=3.1.0,<3.2.0"
 
+[[package]]
+name = "funkify"
+version = "0.4.5"
+description = "Funkify modules so that they are callable"
+optional = false
+python-versions = ">=3.7,<4.0"
+files = [
+    {file = "funkify-0.4.5-py3-none-any.whl", hash = "sha256:43f1e6c27263468a60ba560dfc13e6e4df57aa75376438a62f741ffc7c83cdfe"},
+    {file = "funkify-0.4.5.tar.gz", hash = "sha256:42df845f4afa63e0e66239a986d26b6572ab0b7ad600d7d6365d44d8a0cff3d5"},
+]
+
 [[package]]
 name = "h11"
 version = "0.14.0"
@@ -1106,7 +1133,22 @@ files = [
     {file = "websockets-11.0.3.tar.gz", hash = "sha256:88fc51d9a26b10fc331be344f1781224a375b78488fc343620184e95a4b27016"},
 ]
 
+[[package]]
+name = "xtyping"
+version = "0.7.0"
+description = "xtyping = typing + typing_extensions"
+optional = false
+python-versions = ">=3.7,<4.0"
+files = [
+    {file = "xtyping-0.7.0-py3-none-any.whl", hash = "sha256:5b72b08d5b4775c1ff34a8b7bbdfaae92249aaa11c53b33f26a0a788ca209fda"},
+    {file = "xtyping-0.7.0.tar.gz", hash = "sha256:441e597b227fcb51645e33de7cb47b7b23c014ee7c487a996b312652b8cacde0"},
+]
+
+[package.dependencies]
+annotated-types = ">=0.5.0"
+typing-extensions = ">=4.4.0"
+
 [metadata]
 lock-version = "2.0"
 python-versions = ">=3.11,<3.13"
-content-hash = "5b956fd0da3635be7d6b62b220cb962ba676b0673b9d7f520f49da35c524d2c3"
+content-hash = "5fe0d4c2bffe2fed7a521efa95c416944bc413714eb69a1e13caa8dbff20d1ca"

api/pyproject.toml

@@ -10,7 +10,8 @@ version = "0.1.0"
 
 [tool.poetry.dependencies]
 Pillow = "^10.0.1"
-async-cache = "^1.1.1"
+asyncify = "^0.9.2"
+cachetools = "^5.3.2"
 fastapi = "^0.103.1"
 numpy = "^1.26.0"
 pydantic-settings = "^2.0.3"