blockchain-kit-sdk/com.cramium.blockchain.kit.blockchain.evm/EvmTransactionBuilder

EvmTransactionBuilder

object EvmTransactionBuilder

Builds Ethereum transaction protobufs for use with WalletCore's TransactionCompiler.

This class is responsible for:

Converting SDK transaction models to WalletCore protobuf format
Building SigningInput for native and ERC-20 transfers
Computing preImageHash for external signing (MPC)
Compiling signed transactions from external signatures

Phase 5.1: preImageHash generation Phase 5.2: signature compilation

Functions

buildPreImageHash

fun buildPreImageHash(tx: Transaction, from: String, nonce: BigInteger, fee: Fee): Result<ByteArray>

Build a preImageHash for a transaction.

buildPreImageHashWithSigningInput

fun buildPreImageHashWithSigningInput(tx: Transaction, from: String, nonce: BigInteger, fee: Fee): Result<PreImageHashResult>

Build a preImageHash for a transaction, returning both the PreSigningOutput and the original SigningInput bytes.

compileSignedTransaction

fun compileSignedTransaction(signingInputData: ByteArray, signature: ByteArray, publicKey: ByteArray, network: Network): Result<String>

Compile a signed transaction from preImageHash data and an external signature.

extractDataHash

fun extractDataHash(preImageHash: ByteArray): Result<ByteArray>

Extract the data hash from a preImageHash for signing.

extractSigningInputData

fun ~~extractSigningInputData~~(preImageHash: ByteArray): Result<ByteArray>

Extract data from PreSigningOutput.

getUnsignedTxBytes

fun getUnsignedTxBytes(tx: Transaction, from: String, nonce: BigInteger, fee: Fee): Result<ByteArray>

Returns RLP-encoded unsigned transaction bytes for the given tx/fee. Used by OP Stack L1 fee estimation (GasPriceOracle.getL1Fee(bytes)). Supports both legacy and EIP-1559 (type-2) transactions.