Update app.py

app.py

@@ -52,34 +52,28 @@ builder.add_edge("human_response_display", END)
 SQLITE_DB_PATH = "langgraph_checkpoints.sqlite"
 
 # --- Checkpointer and Graph Compilation ---
-# Initialize global_graph and global_memory_saver
-# The recommended way is to establish the connection once and keep the saver instance.
-# For SqliteSaver, if from_conn_string is a context manager, you need to use `with`.
-# A simpler approach that generally works better for global scope in web apps:
-# Establish a direct SQLite connection and pass it to SqliteSaver.
+global_memory_saver = None # Initialize to None
+
 try:
+    # Attempt to connect to SQLite
     # Use check_same_thread=False for Gradio/web apps that might access the DB from different threads
-    # or if the connection is managed globally.
     conn = sqlite3.connect(SQLITE_DB_PATH, check_same_thread=False)
     global_memory_saver = SqliteSaver(conn=conn)
-    # Ensure tables are created if they don't exist.
-    # SqliteSaver usually does this on first use or you can explicitly call a setup if available.
-    # In recent versions, just passing the connection is often enough for setup.
+    print(f"SqliteSaver initialized successfully: {type(global_memory_saver)}") # ADD THIS LINE
 except Exception as e:
     print(f"Error initializing SqliteSaver connection: {e}")
-    # Fallback or error handling if DB connection fails
-    global_memory_saver = None # Or exit the application
+    # If an error occurs here, global_memory_saver will remain None
 
 if global_memory_saver:
     global_graph = builder.compile(
         checkpointer=global_memory_saver,
         interrupt_before=["human_input_interrupt"]
     )
+    print("Graph compiled successfully.") # ADD THIS LINE
 else:
     print("SqliteSaver not initialized, graph compilation skipped.")
     global_graph = None # Handle the case where checkpointer couldn't be initialized
 
-
 # --- Gradio UI Logic ---
 current_thread_id = gr.State("")
 
@@ -124,6 +118,8 @@ def resume_graph(human_input_from_ui: str, thread_id_state):
         
         current_state_values["human_input"] = human_input_from_ui
 
+        print(f"Type of global_memory_saver before put_state: {type(global_memory_saver)}") # ADD THIS LINE
+
         # Use put_state() from the SqliteSaver instance
         global_memory_saver.put_state(current_state_values, {"configurable": {"thread_id": thread_id_state}})