channel.open

Opens and funds a TIP-20 channel reserve channel.

Usage

import { parseUnits } from 'viem'
import { client } from './viem.config'
 
const { channelId, expiringNonceHash, receipt, salt } =
  await client.channel.openSync({
    deposit: parseUnits('100', 6),
    payee: '0x742d35Cc6634C0532925a3b844Bc9e7595f0bEbb',
    token: '0x20c0000000000000000000000000000000000001',
  })
 
console.log('Channel:', channelId)
console.log('Expiring nonce hash:', expiringNonceHash)
console.log('Salt:', salt)
console.log('Transaction hash:', receipt.transactionHash)

import { Account, createClient } from 'viem/tempo'
 
export const client = createClient({
  account: Account.fromSecp256k1('0x...'),
})

Deterministic Salt

By default, channel.open uses Hex.random(32) for salt. Pass an explicit salt when you need the channel ID to be deterministic for the same channel values.

import { parseUnits } from 'viem'
import { client } from './viem.config'
 
const { channelId } = await client.channel.openSync({
  deposit: parseUnits('100', 6),
  payee: '0x742d35Cc6634C0532925a3b844Bc9e7595f0bEbb',
  salt:
    '0x0000000000000000000000000000000000000000000000000000000000000000',
  token: '0x20c0000000000000000000000000000000000001',
})

Asynchronous Usage

The example above uses a *Sync variant of the action, that will wait for the transaction to be included before returning.

If you are optimizing for performance, you should use the non-sync channel.open action and wait for inclusion manually:

import { parseUnits } from 'viem'
import { Actions } from 'viem/tempo'
import { client } from './viem.config'
 
const hash = await client.channel.open({
  deposit: parseUnits('100', 6),
  payee: '0x742d35Cc6634C0532925a3b844Bc9e7595f0bEbb',
  token: '0x20c0000000000000000000000000000000000001',
})
const receipt = await client.waitForTransactionReceipt({ hash })
 
const { args: { channelId } } =
  Actions.channel.open.extractEvent(receipt.logs)

Return Type

type ReturnType = {
  /** Optional signer for vouchers */
  authorizedSigner: Address
  /** Channel ID */
  channelId: Hex
  /** Amount deposited in the channel */
  deposit: bigint
  /** Transaction-derived hash assigned when the channel was opened */
  expiringNonceHash: Hex
  /** Optional relayer allowed to submit settle for the payee */
  operator: Address
  /** Account that receives settled voucher payments */
  payee: Address
  /** Account that funded the channel and receives refunds */
  payer: Address
  /** Transaction receipt */
  receipt: TransactionReceipt
  /** User-supplied salt */
  salt: Hex
  /** TIP-20 token address held by the channel */
  token: Address
}

Parameters

authorizedSigner (optional)

• Type: Address
• Default: zeroAddress

Optional signer for vouchers. When set to zero address, the payer signs vouchers.

deposit

• Type: bigint

Amount of TIP-20 token to deposit.

operator (optional)

• Type: Address
• Default: zeroAddress

Optional relayer allowed to submit settle for the payee.

payee

• Type: Address

Account that receives settled voucher payments.

salt (optional)

• Type: Hex
• Default: Hex.random(32)

User-supplied salt to distinguish otherwise identical channels.

token

• Type: Address | bigint

TIP-20 token address or ID held by the channel.

account (optional)

• Type: Account | Address

Account that will be used to send the transaction.

feeToken (optional)

• Type: Address | bigint

Fee token for the transaction.

Can be an unpaused USD-denominated TIP-20 token address or ID. Use client.fee.validateToken({ token }) to validate a token before submitting a transaction or setting it as a fee preference.

feePayer (optional)

• Type: Account | true

Fee payer for the transaction.

Can be a Viem Account, or true if a Fee Payer Service will be used.

gas (optional)

• Type: bigint

Gas limit for the transaction.

maxFeePerGas (optional)

• Type: bigint

Max fee per gas for the transaction.

maxPriorityFeePerGas (optional)

• Type: bigint

Max priority fee per gas for the transaction.

nonce (optional)

• Type: number

Nonce for the transaction.

nonceKey (optional)

• Type: 'expiring' | bigint

Nonce key for the transaction. Use 'expiring' to use expiring nonces (TIP-1009), which enables concurrent transaction submission without nonce ordering.

validBefore (optional)

• Type: number

Unix timestamp before which the transaction must be included.

validAfter (optional)

• Type: number

Unix timestamp after which the transaction can be included.

throwOnReceiptRevert (optional)

• Type: boolean
• Default: true

Whether to throw an error if the transaction receipt indicates a revert. Only applicable to *Sync actions.