//public BittrexExchange(KafkaProducer p)
        public BittrexExchange(string bootstrapServers, string topic)
        {
            var evKeys = Environment.GetEnvironmentVariable(ApiKeyEnvVar, EnvironmentVariableTarget.User);
            var keys = evKeys.Split('|');

            var clientOptions = new BittrexClientOptions();
            clientOptions.ApiCredentials = new ApiCredentials(keys[0], keys[1]);
            this.exch = new BittrexClient(clientOptions);
            //----------
            var socketOptions = new BittrexSocketClientOptions();
            socketOptions.ApiCredentials = clientOptions.ApiCredentials;
            this.sock = new BittrexSocketClient(socketOptions);

            //_p = p;
            _p = new KafkaProducer(bootstrapServers, topic);
        }