Transfer Near tokens on behalf of a controlled account

const accessKey = await near.connection.provider.query({
  request_type: "view_access_key",
  account_id: controllableAccountId, // "controllable.testnet"
  public_key: derivedPublicKey, // derived in the previous chapter
  finality: "optimistic",
});

const nonce = accessKey.nonce;

const block = await near.connection.provider.block({
  finality: "final",
});

const blockHash = block.header.hash;

const transactionArgs = {
  signer_id: controllableAccountId, // "controllable.testnet"
  signer_pk: derivedPublicKey, // derived in the previous chapter
  nonce: (nonce + 1).toString(),
  block_hash: blockHash,
};

const adminAccount = await near.account("admin.testnet");

const outcome = await adminAccount.functionCall({
  contractId: contractId, // "broken-rock.testnet"
  methodName: "transfer_on_behalf_of",
  args: {
    args: transactionArgs,
  },
  gas: "300000000000000",
  attachedDeposit: "100000000000000000000000", // 0.1 NEAR is enough in most cases to pay MPC fee
});

// Get the signed transaction from the outcome
result = providers.getTransactionLastResult(outcome);
const signedTx = new Uint8Array(result);

// Send the signed transaction
const transferOutcome = await near.connection.provider.sendJsonRpc(
  "broadcast_tx_commit",
  [Buffer.from(signedTx).toString("base64")]
);

console.log(
  `https://nearblocks.io/txns/${transferOutcome.transaction_outcome.id}`
);