npm package: @kompose-app/hw-subproviders-klaytn
Description: <img alt="Ledger Nano S" src="https://raw.githubusercontent.com/kompose-app/hw-subproviders-klaytn/master/doc/ledger.png" width="200px" />
Latest version: 1.1.0

# hw-subproviders-klaytn
<img alt="Ledger Nano S" src="https://raw.githubusercontent.com/kompose-app/hw-subproviders-klaytn/master/doc/ledger.png" width="200px" />

A higher-level JS package to work with hardware wallets that support [Klaytn](https://klaytn.com). Encodes Klaytn transactions using [CaverJS](https://docs.klaytn.com/bapp/sdk/caver-js) and signs with HD keys managed by corresponding HW subprovider:

* `LedgerSubprovider` supports [Ledger App Klaytn](https://github.com/kompose-app/ledger-app-klaytn) for Ledger Blue, Nano S and (possibly) Nano X.
* `TrezorSubprovider` — _TODO_ 😏
* [D'Cent Wallet](https://dcentwallet.com) — _TODO_ 😏

## Notice

The package is made and provided by community of [Klaytn](https://klaytn.com) and it is not affiliated with GroundX and other Klaytn official partners. However, we work close with Klaytn and Ledger teams to make the original Ledger app approved.

## Contact

For any feedback and communication about this package and "Klaytn" app for Ledger, please join Telegram group [@kompose](https://t.me/kompose)

## API

* Documentation: [hw-subproviders-klaytn.kompose.app](https://hw-subproviders-klaytn.kompose.app/)
* NPM: [@kompose-app/hw-subproviders-klaytn](https://www.npmjs.com/package/@kompose-app/hw-subproviders-klaytn)

## Examples

The `LedgerSubprovider` internally relies on [@kompose-app/hw-app-klaytn](https://github.com/kompose-app/ledger-app-klaytn/tree/master/client-js/packages/hw-app-klaytn) which makes all heavy lifting of APDU communication according to [this](https://github.com/kompose-app/ledger-app-klaytn/blob/master/doc/app-klaytn.md) spec.

### Simple start with U2F Transport (Chrome, Brave, Firefox)

```js
import {
    LedgerSubprovider,
    ledgerKlaytnBrowserClientFactoryAsync
} from '@kompose-app/hw-subproviders-klaytn'

(async () => {
    const subprovider = new LedgerSubprovider({
        networkId: 8217,
        ledgerKlaytnClientFactoryAsync: ledgerKlaytnBrowserClientFactoryAsync,
    })

    try {
        const accounts = await subprovider.getAccountsAsync()
        console.log("Address:", accounts[0])
    } catch (e) {
        console.log(`Error (${e.name}): ${e.message}`)
    }
})()
```

If you get `Error (TransportError): U2F browser support is needed`, then your environement (e.g. NodeJS) is not supporting U2F. And you must use HID or another transports, see the full list at [LedgerHQ's documentation on transports](https://github.com/LedgerHQ/ledgerjs#ledgerhqhw-transport-).

**IMPORTANT!** ⚠️ Recently U2F support has been degraded in Windows 10 operating system, which may cause some issues with Ledger interaction and bad user experience. More information about this can see in this [post](https://www.ledger.com/windows-10-update-sunsetting-u2f-tunnel-transport-for-ledger-devices/) by Ledger team. `ledgerKlaytnBrowserClientFactoryAsync` provided by this package **automatically** tries to use WebUSB by default, compatible with all major platforms. If failed, U2F will be used as a fallback.


### Using a HID transport (e.g. from NodeJS)

```js
import TransportNodeHid from '@ledgerhq/hw-transport-node-hid'
import { LedgerSubprovider } from '@kompose-app/hw-subproviders-klaytn'
import Klaytn from '@kompose-app/hw-app-klaytn'

(async () => {
    const subprovider = new LedgerSubprovider({
        networkId: 8217,
        ledgerKlaytnClientFactoryAsync: async () => {
            const ledgerConnection = await TransportNodeHid.create()
            return new Klaytn(ledgerConnection)
        }
    })

    try {
        const accounts = await subprovider.getAccountsAsync()
        console.log("Address:", accounts[0])
    } catch (e) {
        console.log(`Error (${e.name}): ${e.message}`)
    }
})()
```

Result when Ledger Nano S app is locked:

```
$ BABEL_ENV=development babel-node src/index.js
Error (TransportStatusError): Ledger device: UNKNOWN_ERROR (0x6804)
✨  Done in 3.30s.
```
Result when app is unlocked:

```
$ BABEL_ENV=development babel-node src/index.js
Address: 0x0cbe753e2c47f383eb8c9186f20b660c6e3f79ae
✨  Done in 2.62s.
```

## License

Apache License 2.0