public async Task <UnspentTxOutput[]> GetMempoolUtxos(string address)
{
var transactions = await _dcrdClient.SearchRawTransactions(address,
count : 100,
reverse : true);
// Check if an outpoint is the input to another known transaction.
bool IsSpent(string txId, TxVout txOut) =>
transactions.SelectMany(tx => tx.vin)
.Any(vin => vin.txid == txId && vin.vout == txOut.n);
// Filter out transactions that have a spent outpoint
// Only grab transactions that spend to the provided address.
return((
from transaction in transactions
where transaction.confirmations == 0
from txOut in transaction.vout
where txOut.scriptPubKey.addresses.Contains(address)
where !IsSpent(transaction.txid, txOut)
select new UnspentTxOutput
{
BlockHeight = 0,
BlockIndex = 4294967295,
Hash = transaction.txid,
OutputIndex = (uint)txOut.n,
OutputValue = (long)(txOut.value * (decimal)Math.Pow(10, 8)),
OutputVersion = txOut.version,
PkScript = HexUtil.ToByteArray(txOut.scriptPubKey.hex),
Tree = 0
}).ToArray());
}
private async Task <SearchRawTransactionsResult[]> GetMempoolUtxosInternal(string address)
{
int skip = 0;
int pageSize = 100;
var results = new List <SearchRawTransactionsResult>();
while (true)
{
try
{
// Paginate through the results.
var response = await _dcrdClient.SearchRawTransactions(
address,
skip : skip,
count : pageSize,
reverse : true
);
// If no results, break.
if (response.Result == null || response.Result.Length == 0)
{
break;
}
// Only select unconfirmed transactions.
// If there are less than 100 unconfirmed transactions, then
// we've started to retrieve records that are out of the mempool
// and we can break.
var unconfirmed = response.Result.Where(r => r.Confirmations == 0).ToList();
results.AddRange(unconfirmed);
if (unconfirmed.Count < pageSize)
{
break;
}
skip += response.Result.Length;
}
catch (DcrdException)
{
break;
}
}
return(results.ToArray());
}
