Sponsored Transaction Blocks
The transaction block builder can support sponsored transaction blocks by using the
onlyTransactionKind flag when building the transaction block.
const txb = new TransactionBlock();
// ... add some transactions...
const kindBytes = await txb.build({ provider, onlyTransactionKind: true });
// construct a sponsored transaction from the kind bytes
const sponsoredTxb = TransactionBlock.fromKind(kindBytes);
// you can now set the sponsored transaction data that is required
sponsoredTxb.setSender(sender);
sponsoredTxb.setGasOwner(sponsor);
sponsoredTxb.setGasPayment(sponsorCoins);