public ITransaction Get(object id)
        {
            var transaction = SavedTransactions.FirstOrDefault(i => i.Identifier == id);

            if (transaction == null)
            {
                transaction = CompletedTransactions.FirstOrDefault(i => i.Identifier == id);
            }
            if (transaction == null)
            {
                transaction = VoidedTransactions.FirstOrDefault(i => i.Identifier == id);
            }
            if (transaction == null)
            {
                throw new KeyNotFoundException($"{id} not found in the Transaction store.");
            }
            return(transaction);
        }
 private void DeleteTransaction(ITransaction transaction)
 {
     SavedTransactions.RemoveAll(i => i.Identifier == transaction.Identifier);
     VoidedTransactions.RemoveAll(i => i.Identifier == transaction.Identifier);
     CompletedTransactions.RemoveAll(i => i.Identifier == transaction.Identifier);
 }
 public void StoreCompleted(ITransaction transaction)
 {
     DeleteTransaction(transaction);
     CompletedTransactions.Add(transaction);
 }