public virtual void SetUp(MessageFamily handler)
        {
            _handler        = handler;
            _messageHandler = async(messageName, message) =>
            {
                if ("public-identifier-created".Equals(messageName))
                {
                    var json_identifier = message.GetValue("identifier");
                    var issuerDID       = json_identifier["did"];
                    var issuerVerKey    = json_identifier["verKey"];

                    var trustAnchor = new TrustAnchor(issuerDID.ToString(), issuerVerKey.ToString());
                    await _repository.Add(trustAnchor);

                    await _unitOfWork.Commit();
                }
            };
        }