Helios API/ Building transactions/

Transaction inputs

Each transaction input is an instance of the TxInput class. A TxInput represents a TxOutputId and, when building a new transaction, also contains the underlying TxOutput.

const utxo = new helios.TxInput(
    helios.TxOutputId.fromHex("...", 0n),
    new helios.TxOutput(...) // TxOutput with address, value and datum fields

Spending a regular UTxO

Spending a regular UTxO (i.e. non-script UTxO), is done with the addInput method:


Spending a script UTxO

Spending a UTxO locked at a script address is also done with addInput, but requires specifying a redeemer:

// program.evalParam("...").data can be used directly as 'redeemerData'
tx.addInput(utxo, redeemerData)

The corresponding script must be also be attached to such a transaction:

// 'uplcProgram' is an instance of UplcProgram (i.e. result of helios.Program.new(...).compile(...))