private async Task TransactionsDSCheckAsync(NBitcoin.Block block, long blockInternalId)
{
// Inputs are flattened along with transactionId so they can be checked for double spends.
var allTransactionInputs = block.Transactions.SelectMany(x => x.Inputs.AsIndexedInputs(), (tx, txIn) => new
{
TxId = tx.GetHash().ToBytes(),
TxInput = txIn
}).Select(x => new TxWithInput
{
TxExternalId = x.TxId,
PrevTxId = x.TxInput.PrevOut.Hash.ToBytes(),
Prev_N = x.TxInput.PrevOut.N
});
// Insert raw data and let the database queries find double spends
await txRepository.CheckAndInsertBlockDoubleSpendAsync(allTransactionInputs, appSettings.DeltaBlockHeightForDoubleSpendCheck, blockInternalId);
// If any new double spend records were generated we need to update them with transaction payload
// and trigger notification events
var dsTxIds = await txRepository.GetDSTxWithoutPayloadAsync();
foreach (var(dsTxId, TxId) in dsTxIds)
{
var payload = block.Transactions.Single(x => x.GetHash() == new uint256(dsTxId)).ToBytes();
await txRepository.UpdateDsTxPayloadAsync(dsTxId, payload);
var notificationEvent = new NewNotificationEvent()
{
CreationDate = clock.UtcNow(),
NotificationType = CallbackReason.DoubleSpend,
TransactionId = TxId
};
eventBus.Publish(notificationEvent);
}
await txRepository.SetBlockParsedForDoubleSpendDateAsync(blockInternalId);
}