middleware fixes (warnings) & python 3.13 (#126)

* fix DeprecationWarning
- fix warnings with compression middleware when no compression is used
* add python 3.13 to tested versions as the local tests were working under
python 3.13 and the server_error fix is only required for python 3.13

.github/workflows/test-suite.yml

@@ -20,7 +20,7 @@ jobs:
     runs-on: "ubuntu-latest"
     strategy:
       matrix:
-        python-version: ["3.9", "3.10", "3.11", "3.12"]
+        python-version: ["3.9", "3.10", "3.11", "3.12", "3.13"]
 
     services:
       postgres:

lilya/middleware/compression.py

@@ -2,6 +2,7 @@
 
 import gzip
 import io
+from functools import cached_property
 from typing import NoReturn
 
 from lilya.datastructures import Header
@@ -79,9 +80,10 @@ def __init__(self, app: ASGIApp, minimum_size: int, compresslevel: int = 9) -> N
         self.started = False
         self.content_encoding_set = False
         self.gzip_buffer = io.BytesIO()
-        self.gzip_file = gzip.GzipFile(
-            mode="wb", fileobj=self.gzip_buffer, compresslevel=self.compresslevel
-        )
+
+    @cached_property
+    def gzip_file(self) -> gzip.GzipFile:
+        return gzip.GzipFile(mode="wb", fileobj=self.gzip_buffer, compresslevel=self.compresslevel)
 
     async def __call__(self, scope: Scope, receive: Receive, send: Send) -> None:
         """
@@ -93,7 +95,12 @@ async def __call__(self, scope: Scope, receive: Receive, send: Send) -> None:
             send (Send): The send channel.
         """
         self.send = send
-        await self.app(scope, receive, self.send_with_gzip)
+        try:
+            await self.app(scope, receive, self.send_with_gzip)
+        finally:
+            # ensure cleanup if file is initialized
+            if "gzip_file" in self.__dict__ and not self.gzip_file.closed:
+                self.gzip_file.close()
 
     async def send_with_gzip(self, message: Message) -> None:
         """

lilya/middleware/server_error.py

@@ -195,10 +195,12 @@ def generate_html(self, exc: Exception) -> str:
                 is_collapsed = True
 
         # escape error class and text
-        error = (
-            f"{html.escape(traceback_obj.exc_type.__name__)}: "
-            f"{html.escape(str(traceback_obj))}"
-        )
+        try:
+            exc_type_str = traceback_obj.exc_type_str
+        except Exception:
+            # for older python versions < 3.13
+            exc_type_str = traceback_obj.exc_type.__name__
+        error = f"{html.escape(exc_type_str)}: " f"{html.escape(str(traceback_obj))}"
 
         template = get_template_errors()
         return template.format(styles=get_css_style(), js=get_js(), error=error, exc_html=exc_html)