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createConfig

Creates new Config object.

Import

ts
import { createConfig } from '@wagmi/core'

Usage

ts
import { createConfig, http } from '@wagmi/core'
import { mainnet, sepolia } from '@wagmi/core/chains'

const config = createConfig({
  chains: [mainnet, sepolia],
  transports: {
    [mainnet.id]: http('https://mainnet.example.com'),
    [sepolia.id]: http('https://sepolia.example.com'),
  },
})

Integrating a Viem Client

Instead of using transports, it's possible to provide a function that returns a Viem Client via the client property for more fine-grained control over Wagmi's internal Client creation.

ts
import { createConfig, http } from '@wagmi/core'
import { mainnet, sepolia } from '@wagmi/core/chains'
import { createClient } from 'viem'

const config = createConfig({
  chains: [mainnet, sepolia],
  client({ chain }) {
    return createClient({ chain, transport: http() })
  },
})

Parameters

ts
import { type CreateConfigParameters } from '@wagmi/core'

chains

readonly [Chain, ...Chain[]]

  • Chains used by the Config.
  • See Chains for more details about built-in chains and the Chain type.
ts
import { createConfig, http } from '@wagmi/core'
import { mainnet, sepolia } from '@wagmi/core/chains'

const config = createConfig({
  chains: [mainnet, sepolia], 
  transports: {
    [mainnet.id]: http('https://mainnet.example.com'),
    [sepolia.id]: http('https://sepolia.example.com'),
  },
})

connectors

CreateConnectorFn[] | undefined

Connectors used by the Config.

ts
import { createConfig, http } from '@wagmi/core'
import { mainnet, sepolia } from '@wagmi/core/chains'
import { injected } from '@wagmi/connectors'

const config = createConfig({
  chains: [mainnet, sepolia],
  connectors: [injected()], 
  transports: {
    [mainnet.id]: http('https://mainnet.example.com'),
    [sepolia.id]: http('https://sepolia.example.com'),
  },
})

multiInjectedProviderDiscovery

boolean | undefined

  • Enables discovery of injected providers via EIP-6963 using the mipd library and converting to injected connectors.
  • Defaults to true.
ts
import { createConfig, http } from '@wagmi/core'
import { mainnet, sepolia } from '@wagmi/core/chains'

const config = createConfig({
  chains: [mainnet, sepolia],
  multiInjectedProviderDiscovery: false, 
  transports: {
    [mainnet.id]: http('https://mainnet.example.com'),
    [sepolia.id]: http('https://sepolia.example.com'),
  },
})

ssr

boolean | undefined

Flag to indicate if the config is being used in a server-side rendering environment. Defaults to false.

ts
import { createConfig, createStorage, http } from '@wagmi/core'
import { mainnet, sepolia } from '@wagmi/core/chains'

const config = createConfig({
  chains: [mainnet, sepolia],
  ssr: true, 
  transports: {
    [mainnet.id]: http('https://mainnet.example.com'),
    [sepolia.id]: http('https://sepolia.example.com'),
  },
})

storage

Storage | null | undefined

  • Storage used by the config. Persists Config's State between sessions.
  • Defaults to createStorage({ storage: typeof window !== 'undefined' && window.localStorage ? window.localStorage : noopStorage }).
ts
import { createConfig, createStorage, http } from '@wagmi/core'
import { mainnet, sepolia } from '@wagmi/core/chains'

const config = createConfig({
  chains: [mainnet, sepolia],
  storage: createStorage({ storage: window.localStorage }), 
  transports: {
    [mainnet.id]: http('https://mainnet.example.com'),
    [sepolia.id]: http('https://sepolia.example.com'),
  },
})

syncConnectedChain

boolean | undefined

ts
import { createConfig, http } from '@wagmi/core'
import { mainnet, sepolia } from '@wagmi/core/chains'

const config = createConfig({
  chains: [mainnet, sepolia],
  syncConnectedChain: false, 
  transports: {
    [mainnet.id]: http('https://mainnet.example.com'),
    [sepolia.id]: http('https://sepolia.example.com'),
  },
})

batch

{ multicall?: boolean | { batchSize?: number | undefined; wait?: number | undefined } | undefined } | { [_ in chains[number]["id"]]?: { multicall?: boolean | { batchSize?: number | undefined; wait?: number | undefined } | undefined } | undefined } | undefined

  • Batch settings. See Viem docs for more info.
  • Defaults to { multicall: true }.
ts
import { createConfig, http } from '@wagmi/core'
import { mainnet, sepolia } from '@wagmi/core/chains'

const config = createConfig({
  chains: [mainnet, sepolia],
  batch: { multicall: true }, 
  transports: {
    [mainnet.id]: http('https://mainnet.example.com'),
    [sepolia.id]: http('https://sepolia.example.com'),
  },
})

cacheTime

number | { [_ in chains[number]['id']]?: number | undefined } | undefined

  • Frequency in milliseconds for polling enabled features. See Viem docs for more info.
  • Defaults to pollingInterval or 4_000.
ts
import { createConfig, http } from '@wagmi/core'
import { mainnet, sepolia } from '@wagmi/core/chains'

const config = createConfig({
  chains: [mainnet, sepolia],
  cacheTime: 4_000, 
  transports: {
    [mainnet.id]: http('https://mainnet.example.com'),
    [sepolia.id]: http('https://sepolia.example.com'),
  },
})

pollingInterval

number | { [_ in chains[number]['id']]?: number | undefined } | undefined

  • Frequency in milliseconds for polling enabled features. See Viem docs for more info.
  • Defaults to 4_000.
ts
import { createConfig, http } from '@wagmi/core'
import { mainnet, sepolia } from '@wagmi/core/chains'

const config = createConfig({
  chains: [mainnet, sepolia],
  pollingInterval: 4_000, 
  transports: {
    [mainnet.id]: http('https://mainnet.example.com'),
    [sepolia.id]: http('https://sepolia.example.com'),
  },
})

transports

Record<chains[number]['id'], Transport>

Mapping of chain IDs to Transports. This mapping is used internally when creating chain-aware Viem Client objects. See the Transport docs for more info.

ts
import { createConfig, fallback, http } from '@wagmi/core'
import { mainnet, sepolia } from '@wagmi/core/chains'

const config = createConfig({
  chains: [mainnet, sepolia],
  transports: { 
    [mainnet.id]: fallback([ 
      http('https://...'), 
      http('https://...'), 
    ]), 
    [sepolia.id]: http('https://...'), 
  }, 
})

client

(parameters: { chain: chains[number] }) => Client<Transport, chains[number]>

Function for creating new Viem Client to be used internally. Exposes more control over the internal Client creation logic versus using the transports property.

ts
import { createClient, http } from 'viem'
import { createConfig } from '@wagmi/core'
import { mainnet, sepolia } from '@wagmi/core/chains'

const config = createConfig({
  chains: [mainnet, sepolia],
  client({ chain }) { 
    return createClient({ chain, transport: http('https://...') }) 
  }, 
})

WARNING

When using this option, you likely want to pass parameters.chain straight through to createClient to ensure the Viem Client is in sync with any active connections.

Return Type

ts
import { type Config } from '@wagmi/core'

Config

Object responsible for managing Wagmi state and internals.

ts
import { type Config } from '@wagmi/core'

chains

readonly [Chain, ...Chain[]]

chains passed to createConfig.

connectors

readonly Connector[]

Connectors set up from passing connectors and multiInjectedProviderDiscovery to createConfig.

state

State<chains>

The Config object's internal state. See State for more info.

storage

Storage | null

storage passed to createConfig.

getClient

(parameters?: { chainId?: chainId | chains[number]['id'] | undefined }): Client<transports[chainId], Extract<chains[number], { id: chainId }>>

Creates new Viem Client object.

ts
import { config } from './config'

const client = config.getClient({ chainId: 1 })
ts
import { createConfig, http } from '@wagmi/core'
import { mainnet, sepolia } from '@wagmi/core/chains'

export const config = createConfig({
  chains: [mainnet, sepolia],
  transports: {
    [mainnet.id]: http('https://mainnet.example.com'),
    [sepolia.id]: http('https://sepolia.example.com'),
  },
})

setState

(value: State<chains> | ((state: State<chains>) => State<chains>)) => void

Updates the Config object's internal state. See State for more info.

ts
import { mainnet } from '@wagmi/core/chains'
import { config } from './config'

config.setState((x) => ({
  ...x,
  chainId: x.current ? x.chainId : mainnet.id,
}))
ts
import { createConfig, http } from '@wagmi/core'
import { mainnet, sepolia } from '@wagmi/core/chains'

export const config = createConfig({
  chains: [mainnet, sepolia],
  transports: {
    [mainnet.id]: http('https://mainnet.example.com'),
    [sepolia.id]: http('https://sepolia.example.com'),
  },
})

WARNING

Exercise caution when using this method. It is intended for internal and advanced use-cases only. Manually setting state can cause unexpected behavior.

subscribe

(selector: (state: State<chains>) => state, listener: (selectedState: state, previousSelectedState: state) => void, options?: { emitImmediately?: boolean | undefined; equalityFn?: ((a: state, b: state) => boolean) | undefined } | undefined) => (() => void)

Listens for state changes matching the selector function. Returns a function that can be called to unsubscribe the listener.

ts
import { config } from './config'

const unsubscribe = config.subscribe(
  (state) => state.chainId,
  (chainId) => console.log(`Chain ID changed to ${chainId}`),
)
unsubscribe()
ts
import { createConfig, http } from '@wagmi/core'
import { mainnet, sepolia } from '@wagmi/core/chains'

export const config = createConfig({
  chains: [mainnet, sepolia],
  transports: {
    [mainnet.id]: http('https://mainnet.example.com'),
    [sepolia.id]: http('https://sepolia.example.com'),
  },
})

State

ts
import { type State } from '@wagmi/core'

chainId

chains[number]['id']

Current chain ID. When syncConnectedChain is true, chainId is kept in sync with the current connection. Defaults to first chain in chains.

connections

Map<string, Connection>

Mapping of unique connector identifier to Connection object.

current

string | undefined

Unique identifier of the current connection.

status

'connected' | 'connecting' | 'disconnected' | 'reconnecting'

Current connection status.

  • 'connecting' attempting to establish connection.
  • 'reconnecting' attempting to re-establish connection to one or more connectors.
  • 'connected' at least one connector is connected.
  • 'disconnected' no connection to any connector.

Connection

ts
import { type Connection } from '@wagmi/core'

accounts

readonly [Address, ...Address[]]

Array of addresses associated with the connection.

chainId

number

Chain ID associated with the connection.

connector

Connector

Connector associated with the connection.

Released under the MIT License.