public TransactionController(
     IAddressValidationService addressValidationService,
     IUnsignedTransactionService txBuilderService,
     ITransactionBroadcastService txBroadcastService)
 {
     _addressValidationService = addressValidationService;
     _txBuilderService         = txBuilderService;
     _txBroadcastService       = txBroadcastService;
 }