export default class WebSocketProxyClient {
    private _port;
    private _isMsgBusConnected;
    private _eventTarget;
    readyState: number;
    constructor(url: string);
    readonly url: string;
    close(): void;
    send(data: string): void;
    addEventListener(event: string, listener: (e: MessageEvent) => void): void;
    removeEventListener(event: string, listener: (e: MessageEvent) => void): void;
}