OpenBMB/ChatDev · error · ValidationError

Session not connected

Error message

Session not connected

What it means

ensure_known_session raises ValidationError when session_id is empty/None before any session lookup — i.e. the caller never supplied a session identifier. Distinct from a non-empty unknown session, this is a malformed-request guard.

Source

Thrown at server/state.py:29

def init_state() -> None:
    """Ensure global singletons are ready for incoming requests."""

    get_websocket_manager()


def get_websocket_manager() -> WebSocketManager:
    global websocket_manager
    if websocket_manager is None:
        websocket_manager = WebSocketManager()
    return websocket_manager


def ensure_known_session(session_id: str, *, require_connection: bool = False) -> WebSocketManager:
    """Return the WebSocket manager if the session is connected or known."""

    manager = get_websocket_manager()
    if not session_id:
        raise ValidationError("Session not connected", details={"session_id": session_id})

    if session_id in manager.active_connections:
        return manager

    if not require_connection and manager.session_store.has_session(session_id):
        return manager

    raise ValidationError("Session not connected", details={"session_id": session_id})

View on GitHub (pinned to 4fb2db0ea9)

Solutions

1. Capture and pass the session id returned at connection/register time
2. Validate session_id is non-empty before calling session-scoped APIs
3. Check for field-name mismatches in the request payload

Example fix

# before
result = execute_workflow(session_id=sid, ...)  # sid may be ''
# after
if not sid:
    raise ValueError("missing session_id; connect first")
result = execute_workflow(session_id=sid, ...)

if not session_id:
    raise ValueError('session_id required — connect first')

def has_session_id(sid: str | None) -> bool:
    return isinstance(sid, str) and bool(sid.strip())

When it happens

Trigger: Calling execute_workflow, execute_batch, upload_attachment, or list_attachments with session_id="" or None (missing query/body field, unset client variable).

Common situations: Client connects but never stores the session id from the handshake; field name mismatch (sessionId vs session_id); default empty string in a form.

Related errors

• Design file not found: {config_path}
• Artifact stream not available
• Invalid session_id: only letters, digits, underscores, and h
• No node types registered; cannot validate workflow
• Unsupported node type '{ntype}' for node '{nid}'. Only {allo

AI-assisted analysis of OpenBMB/ChatDev@4fb2db0ea9 (2026-08-27). Data as JSON: /api/errors/015e445443910a93. Report an issue: GitHub.