Function useWebSocket

packages/core/src/widgets/hooks/data.ts:633–835

(
  ctx: WebSocketHookContext,
  url: string,
  protocol?: string | readonly string[],
  options: UseWebSocketOptions<T> = {},
)

 * Subscribe to a websocket endpoint with message parsing and auto-reconnect.
 */
export function useWebSocket<T = string>(
  ctx: WebSocketHookContext,
  url: string,
  protocol?: string | readonly string[],
  options: UseWebSocketOptions<T> = {},
): UseWebSocketState<T> {
  const [value, setValue] = ctx.useState<T | undefined>(undefined);
  const [loading, setLoading] = ctx.useState<boolean>(true);
  const [connected, setConnected] = ctx.useState<boolean>(false);
  const [reconnectAttempts, setReconnectAttempts] = ctx.useState(0);
  const [error, setError] = ctx.useState<unknown>(undefined);
  const runIdRef = ctx.useRef(0);
  const socketRef = ctx.useRef<WebSocketLike | null>(null);
  const manualCloseRef = ctx.useRef(false);
  const reconnectTimerRef = ctx.useRef<ReturnType<typeof setTimeout> | undefined>(undefined);
  const sendRef = ctx.useRef<((payload: WebSocketSendPayload) => boolean) | undefined>(undefined);
  const closeRef = ctx.useRef<((code?: number, reason?: string) => void) | undefined>(undefined);

  if (!sendRef.current) {
    sendRef.current = (payload: WebSocketSendPayload): boolean => {
      const socket = socketRef.current;
      if (!socket) return false;
      try {
        socket.send(payload);
        return true;
      } catch (nextError) {
        setError(nextError);
        return false;
      }
    };
  }

  if (!closeRef.current) {
    closeRef.current = (code?: number, reason?: string): void => {
      manualCloseRef.current = true;
      if (reconnectTimerRef.current !== undefined) {
        clearTimeout(reconnectTimerRef.current);
        reconnectTimerRef.current = undefined;
      }
      const socket = socketRef.current;
      if (!socket) return;
      try {
        socket.close(code, reason);
      } catch (nextError) {
        setError(nextError);
      } finally {
        socketRef.current = null;
      }
    };
  }

  const enabled = options.enabled ?? true;
  const reconnectMs = normalizeReconnectDelayMs(options.reconnectMs, DEFAULT_STREAM_RECONNECT_MS);
  const parse = options.parse;

  ctx.useEffect(() => {
    runIdRef.current += 1;
    const runId = runIdRef.current;