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Overview

Connectors provide the interface between the Fusion SDK and blockchain providers. They handle signing typed data and making contract calls.

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BlockchainProviderConnector

Interface that all blockchain provider connectors must implement. 
interface BlockchainProviderConnector {
  signTypedData(
    walletAddress: string,
    typedData: EIP712TypedData
  ): Promise<string>

  ethCall(
    contractAddress: string,
    callData: string
  ): Promise<string>
}

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Methods

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signTypedData
function
required
Sign EIP-712 typed dataParameters:
  • walletAddress (string): The wallet address to sign with
  • typedData (EIP712TypedData): The typed data to sign
Returns: Promise<string> - The signature
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ethCall
function
required
Execute an eth_call to read contract stateParameters:
  • contractAddress (string): The contract address to call
  • callData (string): The encoded call data
Returns: Promise<string> - The call result

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PrivateKeyProviderConnector

A blockchain provider connector that uses a private key for signing.

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Constructor

new PrivateKeyProviderConnector(
  privateKey: string,
  web3Provider: Web3Like
)
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privateKey
string
required
The private key to use for signing (with or without 0x prefix)
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web3Provider
Web3Like
required
A Web3-like provider for making contract calls

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Example

import { PrivateKeyProviderConnector } from '@1inch/fusion-sdk'
import Web3 from 'web3'

const web3 = new Web3('https://eth.llamarpc.com')

const connector = new PrivateKeyProviderConnector(
  'your-private-key',
  web3
)

// Use with FusionSDK
const sdk = new FusionSDK({
  url: 'https://api.1inch.dev/fusion',
  network: NetworkEnum.ETHEREUM,
  blockchainProvider: connector
})

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Methods

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signTypedData
function
Parameters:
  • walletAddress (string): Not used, signature is created from private key
  • typedData (EIP712TypedData): The typed data to sign
Returns: Promise<string> - The signature
​
ethCall
function
Parameters:
  • contractAddress (string): The contract address to call
  • callData (string): The encoded call data
Returns: Promise<string> - The call result

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Web3ProviderConnector

A blockchain provider connector that uses a Web3 provider’s signing capabilities.

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Constructor

new Web3ProviderConnector(web3Provider: Web3Like)
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web3Provider
Web3Like
required
A Web3-like provider for signing and making contract calls

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Example

import { Web3ProviderConnector } from '@1inch/fusion-sdk'
import Web3 from 'web3'

const web3 = new Web3(window.ethereum)

const connector = new Web3ProviderConnector(web3)

// Use with FusionSDK
const sdk = new FusionSDK({
  url: 'https://api.1inch.dev/fusion',
  network: NetworkEnum.ETHEREUM,
  blockchainProvider: connector
})

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Methods

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signTypedData
function
Uses eth_signTypedData_v4 RPC methodParameters:
  • walletAddress (string): The wallet address to sign with
  • typedData (EIP712TypedData): The typed data to sign
Returns: Promise<string> - The signature
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ethCall
function
Parameters:
  • contractAddress (string): The contract address to call
  • callData (string): The encoded call data
Returns: Promise<string> - The call result

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Web3Like Interface

A minimal Web3 provider interface compatible with Web3.js. 
interface Web3Like {
  eth: {
    call(transactionConfig: TransactionConfig): Promise<string>
  }
  extend(extension: unknown): any
}
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eth.call
function
required
Execute an eth_call to read contract stateParameters:
  • transactionConfig (TransactionConfig): Transaction configuration with to and data fields
Returns: Promise<string> - The call result
​
extend
function
required
Extend the Web3 instance with custom methodsParameters:
  • extension (unknown): Extension configuration
Returns: any - The extended Web3 instance

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TransactionConfig

interface TransactionConfig {
  data?: string
  to?: string
}
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data
string
The encoded call data
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to
string
The contract address to call

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Provider Compatibility

The Web3Like interface is compatible with:
  • Web3.js (v1.x and v4.x)
  • Ethers.js providers (wrapped)
  • MetaMask and other browser wallets
  • Custom RPC providers

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See Also

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