Release 5.8.8

#### Changelog:
* Feature(backend): Add experimental caching check function.
* Chore(deps): Upgrade backend MD dependency.

requirements.txt

@@ -1,6 +1,6 @@
 # Main packages
 configparserc~=2.0.0
-Markdown~=3.5.0
+Markdown~=3.5.1
 django-environ~=0.11.2
 
 # REST API packages

test_src/test_proj/tests.py

@@ -3559,7 +3559,7 @@ def test_cacheable_model(self):
         ])
         self.assertEqual(results[0]['status'], 200)
         self.assertEqual(results[0]['data']['count'], 2)
-        self.assertEqual(results[1]['status'], 304)
+        self.assertEqual(results[1]['status'], 304, results[1]['data'])
         self.assertEqual(results[2]['status'], 200)
         self.assertEqual(results[2]['data']['id'], instance.id)
         self.assertEqual(results[3]['status'], 304)

vstutils/__init__.py

@@ -1,2 +1,2 @@
 # pylint: disable=django-not-available
-__version__: str = '5.8.7'
+__version__: str = '5.8.8'

vstutils/api/base.py

@@ -496,6 +496,28 @@ class EtagDependency(enum.Flag):
     LANG = enum.auto()
 
 
+def check_request_etag(request, etag_value, header_name="If-None-Match", operation_handler=str.__eq__):
+    header = request.headers.get(header_name)
+
+    if not header:
+        return etag_value, False
+
+    header = str(header)
+    if header[:2] in {'W/', "w/"}:
+        header = header[2:]
+
+    if header[0] != '"':
+        header = f'"{header}"'
+
+    if etag_value[0] != '"':
+        etag_value = f'"{etag_value}"'
+
+    if operation_handler(etag_value, header):
+        return etag_value, True
+
+    return etag_value, False
+
+
 class CachableHeadMixin(GenericViewSet):
     """
     Mixin which cache GET responses.
@@ -550,16 +572,14 @@ def check_etag(self, request, model_class=None):
             # For non-standart request methods
             return  # nocv
 
-        header = request.headers.get(header_name, None)
-        if not header:
-            return
-        data = self._get_etag(model_class or self.model_class, request)
-        header = str(header)
-        if header[:2] in ('W/', "w/"):
-            header = header[2:]
-        if header[0] != '"':
-            header = f'"{header}"'
-        if operation_handler(data, header):
+        _, match = check_request_etag(
+            request,
+            self.get_etag_value(model_class or self.model_class, request),
+            header_name,
+            operation_handler,
+        )
+
+        if match:
             raise exception
 
     def finalize_response(self, request, response, *args, **kwargs):

vstutils/api/base.pyi

@@ -91,6 +91,14 @@ class EtagDependency(enum.Flag):
     SESSION: enum.auto()
     LANG: enum.auto()
 
+def check_request_etag(
+        request: Request,
+        etag_value: T,
+        header_name: _t.Text = "If-None-Match",
+        operation_handler: _t.Callable[[_t.Text, _t.Text], bool] = str.__eq__
+) -> _t.Tuple[T, bool]:
+    ...
+
 class CachableHeadMixin(GenericViewSet):
     class NotModifiedException(exceptions.APIException): ...
     class PreconditionFailedException(exceptions.APIException): ...