> For the complete documentation index, see [llms.txt](https://biot-ws.gitbook.io/biot-core/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://biot-ws.gitbook.io/biot-core/channels/auto-re-new-channels.md).

# Auto renewable channels

This class is intended for automatic opening of new channels when the specified balance is reached and automatic payment from the current channel. Example: <https://github.com/BIoTws/endless-channels-example>

### Constructor

walletId - String

timeout - Number - in ms

maxOpenChannels - Number

timeForMutualClosingChannel - Number

## Example: init

{% tabs %}
{% tab title="JS module" %}

```javascript
const autoRenewableChannel = new AutoRenewableChannel(wallets[0], peerDeviceAddress, 20000, 2);
	
await autoRenewableChannel.openNewChannel({
	walletId: wallets[0],
	peerAddress: null,
	myAmount: 100,
	peerAmount: 100,
	age: 10
});
```

{% endtab %}
{% endtabs %}

## Example: channel approval

{% tabs %}
{% tab title="JS module" %}

```javascript
const core = require('biot-core');
const AutoRenewableChannel = require('biot-core/lib/AutoRenewableChannel');

async function start() {
	await core.init('test');
	let wallets = await core.getMyDeviceWallets();
	
	const autoRenewableChannel = new AutoRenewableChannel(wallets[0], null, 20000, 2);
	autoRenewableChannel.init();
	autoRenewableChannel.events.on('start', console.error);
	autoRenewableChannel.events.on('new_transfer', (amount, message, id) => {
		console.error('new transfer', amount, message, id);
	});
	autoRenewableChannel.events.on('request_approve_channel', async (objInfo) => {
		console.error('new Channel: ', objInfo);
		console.error(await autoRenewableChannel.approve(objInfo.index));
	});
}

start().catch(console.error);

```

{% endtab %}
{% endtabs %}

## Events

#### Error

```javascript
autoRenewableChannel.events.on('error', (error, id) => {
		console.error('channelError', id, error);
	});
```

#### start

This event is triggered once at the start of the first channel. The event fires after approve channel.

```javascript
autoRenewableChannel.events.on('start', (id) => {
			console.error('channel start:', id);
		});
```

#### init

init autoRenewableChannel

```javascript
autoRenewableChannel.events.on('init', stats => {
    console.error(peerId, device_address timeForMutualClosingChannel);
});
```

#### request\_approve\_channel

This event notifies us of the request to open the first channel. Contains technical information.

**Structure objInfo:**

**peerDeviceAddress -** String - peer device address for opening channel

**myAddress** - String - peer byteball address

**peerAmount** - Number - your amount in bytes

**myAmount**: - Number - peer amount in bytes

**age** - Number - Timeout in MCI for withdrawal bytes from channel when using one-side closure

**id** - String - channel id

**myUnilateralAddress** - Array - The address of the peer for signing transactions inside the channel

**myDestinationAddress** - Array - The address of the peer for withdrawal from the channel

{% tabs %}
{% tab title="JS module" %}

```javascript
autoRenewableChannel.events.on('request_approve_channel', async (objInfo) => {
    console.error('info: ', objInfo); //request to open
    if (objInfo.peerAmount === 100) {
		await autoRenewableChannel.approve(objInfo.id);
	} else {
	    await autoRenewableChannel.reject(objInfo.id);
	}
});
```

{% endtab %}
{% endtabs %}

#### changed\_step

```javascript
autoRenewableChannel.events.on('changed_step', (step, id) => {
			console.error('changed_step: ', step, id);
		});
```

#### new\_transfer

```javascript
autoRenewableChannel.events.on('new_transfer', async (amount, message, id) => {
			console.error('new_transfer: ', amount, message, id);
			
		});
```