> ## Documentation Index
> Fetch the complete documentation index at: https://docs.peaq.xyz/llms.txt
> Use this file to discover all available pages before exploring further.

# Ensure Machine NFT Allowance

## `mnft.ensureMachineNftAllowance(EnsureMachineNftAllowance)`

Ensure the ERC20 allowance for the Machine NFT registration account is sufficient to cover the registration fee for N machines of a given value. If the allowance is insufficient, it submits an approval transaction.

### EnsureMachineNftAllowance Type Parameters

| Parameter             | Type     | Required | Description                                                          |
| --------------------- | -------- | -------- | -------------------------------------------------------------------- |
| **machineController** | `Signer` | Required | Signer that will pay the ERC20 fee. Must be connected to a provider. |
| **machineNft**        | `string` | Required | Machine NFT contract address.                                        |
| **machineValueHuman** | `string` | Required | Machine value in human-readable units (e.g., `"10"`).                |
| **erc20**             | `string` | Required | ERC20 token address used to pay the fee.                             |
| **tokenDecimals**     | `number` | Required | ERC20 token decimals.                                                |
| **machineCount**      | `number` | Required | Number of machines to register.                                      |

### Returns

| Field                 | Type                               | Description                                  |
| --------------------- | ---------------------------------- | -------------------------------------------- |
| **status**            | `approved` or `already_sufficient` | Whether an approval was sent.                |
| **machineNft**        | `string`                           | Machine NFT contract address.                |
| **feeToken**          | `string`                           | ERC20 token address used for fees.           |
| **feePerMachine**     | `bigint`                           | Fee per machine in token units.              |
| **requiredAllowance** | `bigint`                           | Total allowance required for `machineCount`. |
| **currentAllowance**  | `bigint`                           | Current allowance after the check/approval.  |
| **receipt**           | `TransactionReceipt`               | Only present when `status` is `'approved'`.  |

### Usage

#### TypeScript

```TypeScript theme={"theme":{"light":"github-light-default","dark":"github-dark"}}
import 'dotenv/config';
import { RWA, Chain, type SDKInit } from "@peaq-network/rwa";
import { JsonRpcProvider, Wallet } from "ethers";

async function main() {
  // 0. Create RWA instance and get provider
  const provider = new JsonRpcProvider(process.env.HTTPS_BASE_URL);
  const init: SDKInit = { chainId: Chain.AGUNG, provider: provider };
  const rwa_sdk = new RWA(init);

  // 1. Machine controller (pays ERC20 fee via allowance)
  const alice = new Wallet(process.env.ALICE_PRIVATE_KEY!, provider);

  // 2. Ensure allowance
  const result = await rwa_sdk.mnft.ensureMachineNftAllowance({
    machineController: alice,
    machineNft: "0x5Ca3db1f292f913DDdA8C5385E5391438665463c",
    machineValueHuman: "10",
    erc20: rwa_sdk.getAddresses().erc20.peaq,
    tokenDecimals: 18,
    machineCount: 2
  });
  console.log("Result", result);
}

main().catch((err) => {
  console.error(err);
  process.exit(1);
});
```

#### JavaScript

```js theme={"theme":{"light":"github-light-default","dark":"github-dark"}}
import 'dotenv/config';
import { RWA, Chain } from "@peaq-network/rwa";
import { JsonRpcProvider, Wallet } from "ethers";

async function main() {
  // 0. Create RWA instance and get provider
  const provider = new JsonRpcProvider(process.env.HTTPS_BASE_URL);
  const rwa_sdk = new RWA({ chainId: Chain.AGUNG, provider });

  // 1. Machine controller (pays ERC20 fee via allowance)
  const alice = new Wallet(process.env.ALICE_PRIVATE_KEY, provider);

  // 2. Ensure allowance
  const result = await rwa_sdk.mnft.ensureMachineNftAllowance({
    machineController: alice,
    machineNft: "0x5Ca3db1f292f913DDdA8C5385E5391438665463c",
    machineValueHuman: "10",
    erc20: rwa_sdk.getAddresses().erc20.peaq,
    tokenDecimals: 18,
    machineCount: 2
  });
  console.log("Result", result);
}

main().catch((err) => {
  console.error(err);
  process.exit(1);
});
```

### Example outputs

```
Result {
  status: 'approved',
  machineNft: '0x5Ca3db1f292f913DDdA8C5385E5391438665463c',
  feeToken: '0x...',
  feePerMachine: 10000000000000000000n,
  requiredAllowance: 20000000000000000000n,
  currentAllowance: 20000000000000000000n,
  receipt: ContractTransactionReceipt {
    ...
  }
}
```