History Client looks for 'config' field in JSON, which is not there.

[cvonelm]

void HistoryClient::config(const metricq::json& config)
{
    history_config(config);

    if (!history_exchange_.empty() &&
        config["historyExchange"].get<std::string>() != history_exchange_)
    {
        log::fatal("changing historyExchange on the fly is not currently supported");
        std::abort();
    }

    history_exchange_ = config["historyExchange"].get<std::string>();
    history_queue_ = config["historyQueue"].get<std::string>();

    on_history_config(config["config"]);

    setup_history_queue();

    on_history_ready();
}

The call to on_history_config["config"]) fails because the config json does not seem to contain a config field. Uncommenting the call to on_history_config (which is a callback one has to implement in the specialization of the HistoryClient, but which does not need to do anything). results in correct results.

This issue can be replicated with the history client example program contained in this repository.