chg: [Pub/Sub] Internal Pub/Sub improvements in management of backgro…

…und publishing.

website/stream/listeners.py

@@ -1,7 +1,8 @@
 from typing import Any
 
-import threading
 import json
+import logging
+from concurrent.futures import ThreadPoolExecutor
 from datetime import datetime, timezone
 
 from flask import url_for
@@ -16,11 +17,31 @@
 from website.web.bootstrap import vulnerabilitylookup
 
 
+logging.config.dictConfig(get_config("logging"))
+
+executor = ThreadPoolExecutor(max_workers=10)
+
+
+def handle_exception(future: Any) -> None:
+    try:
+        future.result()  # Retrieve the result of the task; raises if an exception occurred
+    except Exception as e:
+        logging.error(f"Background task failed: {e}", exc_info=True)
+
+
 def publish_in_background(channel: str, message: str) -> None:
     """Offload the publishing logic to a background thread to avoid blocking the database transaction."""
-    threading.Thread(
-        target=vulnerabilitylookup.redis_client.publish, args=(channel, message)
-    ).start()
+
+    def task() -> None:
+        try:
+            vulnerabilitylookup.redis_client.publish(channel, message)
+        except Exception as e:
+            logging.error(f"Error in publish_in_background: {e}", exc_info=True)
+            raise  # Optionally re-raise the exception if needed
+
+    future = executor.submit(task)
+    # Optionally handle the exception when the future is retrieved
+    future.add_done_callback(handle_exception)
 
 
 def stream_comment(mapper: Mapper, connection: Connection, target: Any) -> None:  # type: ignore[type-arg]