Update app.py

app.py

@@ -20,24 +20,42 @@ MAX_HISTORY_TURNS = 10  # Maximum conversation turns to keep in context
 client = genai.Client(api_key=GEMINI_KEY)
 user_memory = {}  # { user_id: { "history": [], "last_sync": timestamp } }
 
-# --- Background thread for periodic flush ---
+# --- Helper: sync single user's history (added) ---
+def sync_user(uid):
+    """
+    Attempt to sync a single user's most recent history to LAMBDA_URL.
+    Updates user_memory[uid]['last_sync'] on success and logs results.
+    This runs in its own thread when called from update_user_history and in the flush loop.
+    """
+    try:
+        data = user_memory.get(uid)
+        if not data:
+            return
+        history_to_sync = data["history"][-MAX_HISTORY_TURNS:]
+        payload = {"user_id": uid, "history": history_to_sync}
+        resp = requests.post(LAMBDA_URL, json=payload, timeout=5)
+        resp.raise_for_status()
+        user_memory[uid]["last_sync"] = time.time()
+        app.logger.info(f"Synced memory for {uid} ({len(history_to_sync)} turns)")
+    except Exception as e:
+        app.logger.warning(f"Failed sync for {uid}: {e}")
+
+# --- Background thread for periodic flush (uses helper) ---
 def flush_loop():
     while True:
         now = time.time()
         for uid, data in list(user_memory.items()):
-            if now - data.get("last_sync", 0) >= FLUSH_INTERVAL and data["history"]:
-                try:
-                    # Only sync the most recent MAX_HISTORY_TURNS entries
-                    history_to_sync = data["history"][-MAX_HISTORY_TURNS:]
-                    payload = {"user_id": uid, "history": history_to_sync}
-                    requests.post(LAMBDA_URL, json=payload, timeout=5)
-                    user_memory[uid]["last_sync"] = now
-                    app.logger.info(f"Synced memory for {uid} ({len(history_to_sync)} turns)")
-                except Exception as e:
-                    app.logger.warning(f"Failed sync for {uid}: {e}")
+            if now - data.get("last_sync", 0) >= FLUSH_INTERVAL and data.get("history"):
+                # Offload the actual network call to a short-lived thread so the loop isn't blocked.
+                threading.Thread(target=sync_user, args=(uid,), daemon=True).start()
         time.sleep(5)
 
-threading.Thread(target=flush_loop, daemon=True).start()
+# NOTE: don't start the thread at module import time to avoid issues with Flask reloader.
+# We'll start it once when the app starts serving requests.
+def start_flush_thread_once():
+    t = threading.Thread(target=flush_loop, daemon=True)
+    t.start()
+    app.logger.info("Started flush background thread")
 
 # --- HTML Frontend ---
 HTML = """
@@ -161,6 +179,9 @@ def update_user_history(uid, prompt, response):
     if len(user_memory[uid]["history"]) > MAX_HISTORY_TURNS:
         user_memory[uid]["history"] = user_memory[uid]["history"][-MAX_HISTORY_TURNS:]
         app.logger.debug(f"Trimmed history for {uid} to {MAX_HISTORY_TURNS} turns")
+    
+    # Attempt immediate async sync so you can see logs quickly (added)
+    threading.Thread(target=sync_user, args=(uid,), daemon=True).start()
 
 # --- Routes ---
 @app.route("/")
@@ -194,6 +215,10 @@ def gen():
         app.logger.exception("Generation failed")
         return jsonify({"error": str(e)}), 500
 
+# Ensure background thread starts when app begins serving requests
+@app.before_first_request
+def _start_background_tasks():
+    start_flush_thread_once()
 
 if __name__ == "__main__":
     port = int(os.getenv("PORT", 7860))