Custom Transport
The custom Transport accepts an EIP-1193 request function as a parameter. This transport is useful for integrating with injected wallets, wallets that provide an EIP-1193 provider (eg. WalletConnect or Coinbase SDK), or even providing your own custom request function.
Import
ts
import { custom } from 'viem'Usage
You can use any EIP-1193 compatible Ethereum Provider with the custom Transport:
ts
import { createWalletClient, custom } from 'viem'
import { mainnet } from 'viem/chains'
const client = createWalletClient({
chain: mainnet,
transport: custom(window.ethereum)
})Or you can define your own:
ts
import { createWalletClient, custom } from 'viem'
import { mainnet } from 'viem/chains'
import { customRpc } from './rpc'
const client = createWalletClient({
chain: mainnet,
transport: custom({
async request({ method, params }) {
const response = await customRpc.request(method, params)
return response
}
})
})Parameters
provider
- Type:
custom
An EIP-1193 request function function.
ts
import { customRpc } from './rpc'
const transport = custom({
async request({ method, params }) {
const response = await customRpc.request(method, params)
return response
}
})key (optional)
- Type:
string - Default:
"custom"
A key for the Transport.
ts
const transport = custom(
window.ethereum,
{
key: 'windowProvider',
}
)name (optional)
- Type:
string - Default:
"Ethereum Provider"
A name for the Transport
ts
const transport = custom(
window.ethereum,
{
name: 'Window Ethereum Provider',
}
)retryCount (optional)
- Type:
number - Default:
3
The max number of times to retry when a request fails.
ts
const transport = custom(window.ethereum, {
retryCount: 5,
})retryDelay (optional)
- Type:
number - Default:
150
The base delay (in ms) between retries. By default, the Transport will use exponential backoff (~~(1 << count) * retryDelay), which means the time between retries is not constant.
ts
const transport = custom(window.ethereum, {
retryDelay: 100,
})Gotchas
- If you are pairing the
customTransport with a Public Client, ensure that your provider supports Public Actions.