Add per-response access log control and suppress noisy asset 304s

Author: davegaeddert

plain/plain/assets/views.py

@@ -280,9 +280,7 @@ def get_conditional_response(self, path: str) -> NotModifiedResponse | None:
         Support conditional requests (HTTP 304 response) based on ETag and Last-Modified headers.
         """
         if self.request.headers.get("If-None-Match") == self.get_etag(path):
-            response = NotModifiedResponse()
-            response.headers = self.update_headers(response.headers, path)
-            return response
+            return self._not_modified_response(path)
 
         if "If-Modified-Since" in self.request.headers:
             if_modified_since = parsedate(self.request.headers["If-Modified-Since"])
@@ -292,11 +290,16 @@ def get_conditional_response(self, path: str) -> NotModifiedResponse | None:
                 and last_modified
                 and if_modified_since >= last_modified
             ):
-                response = NotModifiedResponse()
-                response.headers = self.update_headers(response.headers, path)
-                return response
+                return self._not_modified_response(path)
         return None
 
+    def _not_modified_response(self, path: str) -> NotModifiedResponse:
+        response = NotModifiedResponse()
+        response.headers = self.update_headers(response.headers, path)
+        if not settings.ASSETS_LOG_304:
+            response.log_access = False
+        return response
+
     def get_range_response(self, path: str) -> Response | StreamingResponse | None:
         """
         Support range requests (HTTP 206 response).

plain/plain/http/response.py

@@ -151,6 +151,8 @@ def __init__(
         self._reason_phrase = reason
         # Exception that caused this response, if any (primarily for 500 errors)
         self.exception: Exception | None = None
+        # Whether the server should log this response in the access log
+        self.log_access: bool = True
 
     @property
     def reason_phrase(self) -> str:

plain/plain/runtime/global_settings.py

@@ -168,6 +168,10 @@
 # Ex. "https://cdn.example.com/assets/"
 ASSETS_CDN_URL: str = ""
 
+# Whether to log 304 Not Modified responses for assets in the access log.
+# Disabled by default to reduce noise from conditional requests.
+ASSETS_LOG_304: bool = False
+
 # MARK: Server
 
 SERVER_WORKERS: int = int(os.environ.get("WEB_CONCURRENCY", 0))  # 0 = auto (CPU count)

plain/plain/server/workers/thread.py

@@ -379,7 +379,8 @@ def handle_request(self, req: Any, conn: TConn) -> bool:
                 resp.write_response(http_response)
             finally:
                 request_time = datetime.now() - request_start
-                self.log.access(resp, req, request_time)
+                if http_response.log_access:
+                    self.log.access(resp, req, request_time)
                 if hasattr(http_response, "close"):
                     http_response.close()