commit

commit is an asynchronous function that commits UTxOs to an initializing Hydra head. This action moves funds from the main chain into the Hydra head, making them available for off-chain transactions.

Function Signature

async commit(utxos: Commit, submit: boolean = false): Promise<CommonTxObject>

Parameters

• utxos: A Commit object specifying the UTxOs to be committed.
• submit: An optional boolean indicating whether to submit the transaction to the chain. Defaults to false.

Returns

A Promise that resolves to a CommonTxObject representing the commitment transaction.

Example

import { readFileSync } from "fs";
import { CardanoKeyAsync, Value } from "libcardano";
import { ShelleyWallet, SimpleCip30Wallet } from "libcardano-wallet";
import { UTxO } from "libcardano/serialization";
import { KuberHydraApiProvider } from "kuber-client";

async function main() {
  const hydra = new KuberHydraApiProvider("http://localhost:8082");
  const signingKey = await CardanoKeyAsync.fromCardanoCliJson(
    JSON.parse(readFileSync("../../kuber-hydra/devnet/credentials/alice-funds.sk", "utf-8")),
  );
  const wallet = new SimpleCip30Wallet(hydra, hydra, new ShelleyWallet(signingKey), 0);
  const walletAddress = (await wallet.getChangeAddress()).toBech32();

  const l1Utxos = await hydra.l1Api.queryUTxOByAddress(walletAddress);
  const selectedUtxo = l1Utxos.find((utxo: UTxO) => utxo.txOut.value.greaterThan(Value.fromString("4A")));
  if (!selectedUtxo) {
    throw new Error(`Alice has no L1 UTxO larger than 4 ADA at ${walletAddress}`);
  }

  const txIn = `${selectedUtxo.txIn.txHash.toString("hex")}#${selectedUtxo.txIn.index}`;

  try {
    console.log("Committing UTxOs...");
    const commitTx = await hydra.commit({ utxos: [txIn] });
    const signedTx = await wallet.signTx(commitTx.cborHex);
    await hydra.l1Api.submitTx(signedTx.transaction.toBytes().toString("hex"));
    console.log("Commit transaction hash:", commitTx.hash);
  } catch (error) {
    console.error("Error committing UTxOs:", error);
  }
}

main();