added context manager to remove errors

app/nodes/archive_node.py

@@ -2,8 +2,13 @@ from app.state.state import EmailAgentState
 from langchain_core.runnables.config import RunnableConfig
 from app.database.connection import get_session
 from app.database.utils import save_received_email
+from contextlib import contextmanager
 
 
+# A Context Manager is your code's automatic cleanup crew. Its only job is to open a resource when you need it, and make sure it gets closed the exact moment you are done
+session_context=contextmanager(get_session)
+
+# We are converting your simple get_session function into a fully functioning Python Context Manager.
 def archive_node(state: EmailAgentState,config: RunnableConfig) -> dict:
 
     print(f"[ARCHIVE] {state['triage_label']} — {state['sender_subject']}")
@@ -15,7 +20,7 @@ def archive_node(state: EmailAgentState,config: RunnableConfig) -> dict:
 
     thread_id = config.get("configurable", {}).get("thread_id")
 
-    with get_session() as session:
+    with session_context() as session:
         try:
             # 2. Persist the received email even if it's unsafe (for records/logging)
             save_received_email(session, user_id, thread_id, state)
@@ -31,4 +36,10 @@ def archive_node(state: EmailAgentState,config: RunnableConfig) -> dict:
             raise e
 
     
-    return {}
+    return {}
+
+
+
+
+# A Context Manager is a brilliant Python tool that automatically handles the setup and cleanup of a resource for you. It guarantees that no matter what happens inside your code—even if an unexpected error crashes the system—your resources (like database connections or files) are safely closed and cleaned up.
+# A context manager is a Python utility used to allocate and release resources precisely when we want them to. By wrapping our database generator with @contextmanager, it allows us to use the standard with statement. This guarantees resource safety, ensuring that our database session is automatically and cleanly closed in the finally block, even if our core logic throws a runtime exception.

app/nodes/store_memory_data_node.py

@@ -8,6 +8,10 @@ from app.database.connection import get_session
 from app.database.utils import save_sent_email, save_received_email
 from langchain_core.messages import AIMessage
 from app.utils.token_utils import *
+from contextlib import contextmanager
+
+
+session_context=contextmanager(get_session)
 
 def store_memory_and_data_node(state: EmailAgentState, config: RunnableConfig):
     """
@@ -52,7 +56,7 @@ def store_memory_and_data_node(state: EmailAgentState, config: RunnableConfig):
     thread_id = config.get("configurable", {}).get("thread_id")
 
     # Using 'with' handles opening/closing even if an error occurs
-    with get_session() as session:
+    with session_context() as session:
         try:
             save_sent_email(session, sender_id, thread_id, state)
             save_received_email(session, sender_id, thread_id, state)

app/nodes/summarise_email_body_node.py

@@ -11,12 +11,8 @@ from app.utils.token_utils import summarise_email_body
 
 def summarise_email_body_node(state:EmailAgentState)->dict:
 
-
     subject=state['sender_subject']
     body=state['sender_email_body']
-
-
-
     summary=summarise_email_body(body)
 
     return {"sender_email_body":summary}

app/nodes/unsafe_email_node.py

@@ -2,6 +2,9 @@ from app.state.state import EmailAgentState
 from langchain_core.runnables.config import RunnableConfig
 from app.database.connection import get_session
 from app.database.utils import save_received_email
+from contextlib import contextmanager
+
+session_context=contextmanager(get_session)
 
 def unsafe_emails_node(state: EmailAgentState, config: RunnableConfig) -> dict:
     """
@@ -14,7 +17,7 @@ def unsafe_emails_node(state: EmailAgentState, config: RunnableConfig) -> dict:
     user_id = state['user_id']
     thread_id = config.get("configurable", {}).get("thread_id")
 
-    with get_session() as session:
+    with session_context() as session:
         try:
             # 2. Persist the received email even if it's unsafe (for records/logging)
             save_received_email(session, user_id, thread_id, state)