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The FeeCollector contract manages fee collection for both LiFi protocol fees and integrator fees. It tracks balances per integrator and token, and allows withdrawal of collected fees.

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Functions

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Fee Collection

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collectTokenFees

Collects fees in ERC20 tokens from a transaction. 
function collectTokenFees(
  tokenAddress: string,
  integratorFee: BigNumberish,
  lifiFee: BigNumberish,
  integratorAddress: string
): Promise<ContractTransaction>
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tokenAddress
address
required
Address of the ERC20 token
​
integratorFee
uint256
required
Amount of tokens to collect as integrator fee
​
lifiFee
uint256
required
Amount of tokens to collect as LiFi protocol fee
​
integratorAddress
address
required
Address of the integrator to credit the fee to

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collectNativeFees

Collects fees in native currency (ETH, MATIC, etc.). 
function collectNativeFees(
  integratorFee: BigNumberish,
  lifiFee: BigNumberish,
  integratorAddress: string
): Promise<ContractTransaction>
​
integratorFee
uint256
required
Amount of native currency to collect as integrator fee
​
lifiFee
uint256
required
Amount of native currency to collect as LiFi protocol fee
​
integratorAddress
address
required
Address of the integrator to credit the fee to

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Fee Withdrawal

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withdrawIntegratorFees

Withdraws collected fees for a specific token (integrator only). 
function withdrawIntegratorFees(
  tokenAddress: string
): Promise<ContractTransaction>
​
tokenAddress
address
required
Address of the token to withdraw (zero address for native)

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withdrawLifiFees

Withdraws LiFi protocol fees for a specific token (owner only). 
function withdrawLifiFees(
  tokenAddress: string
): Promise<ContractTransaction>
​
tokenAddress
address
required
Address of the token to withdraw (zero address for native)

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batchWithdrawIntegratorFees

Withdraws integrator fees for multiple tokens at once. 
function batchWithdrawIntegratorFees(
  tokenAddresses: string[]
): Promise<ContractTransaction>
​
tokenAddresses
address[]
required
Array of token addresses to withdraw

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batchWithdrawLifiFees

Withdraws LiFi protocol fees for multiple tokens at once (owner only). 
function batchWithdrawLifiFees(
  tokenAddresses: string[]
): Promise<ContractTransaction>
​
tokenAddresses
address[]
required
Array of token addresses to withdraw

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View Functions

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getTokenBalance

Gets the fee balance for a specific integrator and token. 
function getTokenBalance(
  integratorAddress: string,
  tokenAddress: string
): Promise<BigNumber>
​
integratorAddress
address
required
Address of the integrator
​
tokenAddress
address
required
Address of the token

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getLifiTokenBalance

Gets the LiFi protocol fee balance for a specific token. 
function getLifiTokenBalance(
  tokenAddress: string
): Promise<BigNumber>
​
tokenAddress
address
required
Address of the token

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Ownership Functions

The FeeCollector implements a two-step ownership transfer pattern:

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transferOwnership

function transferOwnership(_newOwner: string): Promise<ContractTransaction>

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confirmOwnershipTransfer

function confirmOwnershipTransfer(): Promise<ContractTransaction>

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cancelOwnershipTransfer

function cancelOwnershipTransfer(): Promise<ContractTransaction>

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owner

function owner(): Promise<string>

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pendingOwner

function pendingOwner(): Promise<string>

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Events

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FeesCollected

Emitted when fees are collected.
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_token
address
Address of the token (zero for native)
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_integrator
address
Address of the integrator
​
_integratorFee
uint256
Amount collected as integrator fee
​
_lifiFee
uint256
Amount collected as LiFi protocol fee

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FeesWithdrawn

Emitted when integrator fees are withdrawn.
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_token
address
Address of the withdrawn token
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_to
address
Address receiving the fees
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_amount
uint256
Amount withdrawn

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LiFiFeesWithdrawn

Emitted when LiFi protocol fees are withdrawn.
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_token
address
Address of the withdrawn token
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_to
address
Address receiving the fees
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_amount
uint256
Amount withdrawn

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OwnershipTransferRequested

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_from
address
Current owner
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_to
address
Pending new owner

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OwnershipTransferred

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previousOwner
address
Previous owner
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newOwner
address
New owner

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Usage Example

import { FeeCollector__factory } from '@lifi/contract-types';
import { ethers } from 'ethers';

const provider = new ethers.providers.JsonRpcProvider(RPC_URL);
const signer = provider.getSigner();
const feeCollector = FeeCollector__factory.connect(FEE_COLLECTOR_ADDRESS, signer);

// Collect fees in USDC
const usdcAddress = '0xUSDC_ADDRESS';
const integratorFee = ethers.utils.parseUnits('1', 6); // 1 USDC
const lifiFee = ethers.utils.parseUnits('0.5', 6); // 0.5 USDC

const tx = await feeCollector.collectTokenFees(
  usdcAddress,
  integratorFee,
  lifiFee,
  '0xINTEGRATOR_ADDRESS'
);
await tx.wait();

// Check integrator balance
const balance = await feeCollector.getTokenBalance(
  '0xINTEGRATOR_ADDRESS',
  usdcAddress
);
console.log('Integrator USDC balance:', ethers.utils.formatUnits(balance, 6));

// Withdraw integrator fees
const withdrawTx = await feeCollector.withdrawIntegratorFees(usdcAddress);
await withdrawTx.wait();

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