class ws_impl
        : public std::enable_shared_from_this<ws_impl>
    {
        ALLOW_MAKE_SHARED(ws_impl)

    public:
        static std::shared_ptr<ws_impl> create(std::shared_ptr<websocket_client> client, uint32_t archive_idx, qt::qthread_executor& exec, std::shared_ptr<source_model> model, std::shared_ptr<archive_proxy_concurrent> archive)
        {
            auto object = std::make_shared<ws_impl>(client, archive_idx, exec, model, archive);
            object->run();
            return object;
        }
        void shutdown()
        {
            client_->unsubscribe_from_websocket(sources_token_);
        }
        ~ws_impl()
        {
            shutdown();
        }
    private:
        ws_impl(std::shared_ptr<websocket_client> client, uint32_t archive_idx, qt::qthread_executor& exec, std::shared_ptr<source_model> model, std::shared_ptr<archive_proxy_concurrent> archive)
            : client_(client)
            , archive_idx_(archive_idx_)
            , exec_(exec)
            , model_(*model)
            , archive_(archive)
        {
        }
        void run()
        {
            std::string resource = "/sources/";
            sources_token_ = fmt::format("{:x}_{}", ao::bit_cast<uint64_t>(this), resource);
            client_->subscribe_to_websocket(resource, sources_token_, 0,
                boost::asio::bind_post(exec_,
                [this /*, self = shared_from_this() */ , resource](const nlohmann::json& js, boost::system::error_code e)
                {