Aave V3 Pool Contract

This contract is the main user-facing contract. Most user interactions with the Aave Protocol occur via the Pool contract. It exposes the liquidity management methods that can be invoked using either Solidity or Web3 libraries.

Pool.sol allows users to:

• Supply
• Withdraw
• Borrow
• Repay
• Enable/disable supplied assets as collateral
• Liquidate positions
• Execute Flash Loans

Pool is covered by a proxy contract and is owned by the PoolAddressesProvider of the specific market. All admin functions are callable by the PoolConfigurator contract defined in the PoolAddressesProvider.

The source code is available on GitHub.

Write Methods

initialize

function initialize(IPoolAddressesProvider provider) external virtual

Initializes the Pool.

Function is invoked by the proxy contract when the Pool contract is added to the PoolAddressesProvider of the market.

Caches the address of the PoolAddressesProvider in order to reduce gas consumption on subsequent operations.

Input Parameters:

supply

function supply(
    address asset,
    uint256 amount,
    address onBehalfOf,
    uint16 referralCode
) public virtual override

Supplies a certain amount of an asset into the protocol, minting the same amount of corresponding aTokens and transferring them to the onBehalfOf address. For example, if a user supplies 100 USDC and onBehalfOf address is the same as msg.sender, they will get 100 aUSDC in return.

The referralCode is emitted in Supply event and can be for third-party referral integrations. To activate the referral feature and obtain a unique referral code, integrators need to submit a proposal to Aave Governance.

Input Parameters:

supplyWithPermit

function supplyWithPermit(
    address asset,
    uint256 amount,
    address onBehalfOf,
    uint16 referralCode,
    uint256 deadline,
    uint8 permitV,
    bytes32 permitR,
    bytes32 permitS
) public virtual override

Supply with transfer approval of the asset to be supplied via permit function. This method removes the need for separate approval tx before supplying asset to the pool. See EIP-2612.

Input Parameters:

withdraw

function withdraw(address asset, uint256 amount, address to) public virtual override returns (uint256)

Withdraws an amount of underlying asset from the reserve, burning the equivalent aTokens owned. For example, if a user has 100 aUSDC and calls withdraw(), they will receive 100 USDC, burning the 100 aUSDC.

If user has any existing debt backed by the underlying token, then the maximum amount available to withdraw is the amount that will not leave user’s health factor < 1 after withdrawal.

Input Parameters:

Return Values:

borrow

function borrow(
    address asset,
    uint256 amount,
    uint256 interestRateMode,
    uint16 referralCode,
    address onBehalfOf
) public virtual override

Allows users to borrow a specific amount of the reserve underlying asset, provided the borrower has already supplied enough collateral, or they were given enough allowance by a credit delegator on the corresponding debt token (VariableDebtToken). For example, if a user borrows 100 USDC passing their own address as onBehalfOf, they will receive 100 USDC into their wallet and 100 variable debt tokens.

Input Parameters:

repay

function repay(
    address asset,
    uint256 amount,
    uint256 interestRateMode,
    address onBehalfOf
) public virtual override returns (uint256)

Repays a borrowed amount on a specific reserve, burning the equivalent debt tokens owned. For example, if a user repays 100 USDC, the 100 variable debt tokens owned by the onBehalfOf address will be burned.

Input Parameters:

repayWithPermit

function repayWithPermit(
    address asset,
    uint256 amount,
    uint256 interestRateMode,
    address onBehalfOf,
    uint256 deadline,
    uint8 permitV,
    bytes32 permitR,
    bytes32 permitS
) public virtual override returns (uint256)

Repay with transfer approval of the borrowed asset to be repaid, done via permit function. This method removes the need for separate approval tx before repaying asset to the pool. See EIP-2612.

Input Parameters:

Return Values:

repayWithATokens

function repayWithATokens(address asset, uint256 amount, uint256 interestRateMode
) public virtual override returns (uint256)

Allows a user to repay a borrowed amount on a specific reserve using the reserve aTokens, burning the equivalent debt tokens. For example, a user repays 100 USDC using 100 aUSDC, burning 100 variable debt tokens. Passing type(uint256).max as the amount will clean up any residual aToken dust balance, if the user aToken balance is not enough to cover the whole debt.

Input Parameters:

Return Values:

setUserUseReserveAsCollateral

function setUserUseReserveAsCollateral(address asset, bool useAsCollateral) public virtual override

Allows suppliers to enable/disable a specific supplied asset as collateral. Sets the asset of msg.sender to be used as collateral or not.

Input Parameters:

liquidationCall

function liquidationCall(
    address collateralAsset,
    address debtAsset,
    address user,
    uint256 debtToCover,
    bool receiveAToken
) public virtual override

Function to liquidate a non-healthy position collateral-wise, with Health Factor below 1.

When the health factor of a position is below 1, the caller (liquidator) repays the debtToCover amount of debt of the user getting liquidated. This is part or all of the outstanding borrowed amount on behalf of the borrower. The caller then receives a proportional amount of the collateralAsset (discounted amount of collateral) plus a liquidation bonus to cover market risk.

Liquidators can decide if they want to receive an equivalent amount of collateral aTokens instead of the underlying asset. When the liquidation is completed successfully, the health factor of the position is increased, bringing the health factor above 1.

Liquidators can repay up to 50% of the user’s total debt. The full debt of the reserve can be liquidated when the health factor is at or below 0.95, or when the user’s collateral or debt in the reserve is worth less than 2,000 base currency units (USD on most markets). The liquidation discount applies to this amount. See Liquidations.

• In most scenarios, profitable liquidators will choose to liquidate as much as they can.
• debtToCover parameter can be set to type(uint256).max and the protocol will proceed with the highest possible liquidation allowed by the close factor.
• To check a user’s health factor, use getUserAccountData().

Input Parameters:

flashLoan

function flashLoan(
    address receiverAddress,
    address[] calldata assets,
    uint256[] calldata amounts,
    uint256[] calldata interestRateModes,
    address onBehalfOf,
    bytes calldata params,
    uint16 referralCode
) public virtual override

Allows users to access liquidity of the pool for a given list of assets within one transaction, as long as the amount taken plus a fee is returned. The receiver must approve the Pool contract for at least the amount borrowed + fee, otherwise the transaction will revert.

The flash loan fee is waived for approved FLASH_BORROWER.

Input Parameters:

flashLoanSimple

function flashLoanSimple(
    address receiverAddress,
    address asset,
    uint256 amount,
    bytes calldata params,
    uint16 referralCode
) public virtual override

Allows users to access liquidity of the pool for a given asset within one transaction, as long as the amount taken plus a fee is returned. The receiver must approve the Pool contract for at least the amount borrowed + fee, otherwise the transaction will revert.

This function does not waive the fee for approved FLASH_BORROWER, nor does it allow for opening a debt position instead of repaying.

Input Parameters:

mintToTreasury

function mintToTreasury(address[] calldata assets) external virtual override

Mints the assets accrued through the reserve factor to the treasury in the form of aTokens for the given list of assets.

Input Parameters:

finalizeTransfer

function finalizeTransfer(
    address asset,
    address from,
    address to,
    uint256 scaledAmount,
    uint256 scaledBalanceFromBefore
) external virtual override

Validates and finalizes an aToken transfer. It is only callable by the overlying aToken of the asset.

Input Parameters:

setUserEMode

function setUserEMode(uint8 categoryId) external virtual override

Allows a user to use the protocol in efficiency mode. The category id must be a valid id already defined by Pool or Risk Admins.

Input Parameters:

initReserve

function initReserve(
    address asset,
    address aTokenAddress,
    address variableDebtAddress
) external virtual override onlyPoolConfigurator

Initializes a reserve, activating it, assigning an aToken and debt tokens. All reserves share the interest rate strategy returned by RESERVE_INTEREST_RATE_STRATEGY().

Input Parameters:

setConfiguration

function setConfiguration(address asset, DataTypes.ReserveConfigurationMap calldata configuration) external virtual override onlyPoolConfigurator

Sets the configuration bitmap of the reserve as a whole.

Input Parameters:

See the bit layout under getConfiguration.

updateFlashloanPremium

function updateFlashloanPremium(uint128 flashLoanPremium) external virtual override onlyPoolConfigurator

Updates the flash loan premium. The protocol treasury collects the whole premium, which is calculated on the total borrowed amount.

Input Parameters:

configureEModeCategory

function configureEModeCategory(uint8 id, DataTypes.EModeCategoryBaseConfiguration calldata category) external virtual override onlyPoolConfigurator

Configures a new eMode category or alters an existing one. In eMode, the protocol allows very high borrowing power to borrow assets of the same category. The category 0 is reserved for volatile heterogeneous assets and it’s always disabled.

Input Parameters:

The DataTypes.EModeCategoryBaseConfiguration struct is composed of the following fields:

configureEModeCategoryIsolated

function configureEModeCategoryIsolated(uint8 id, bool isolated) external virtual override onlyPoolConfigurator

Sets the isolated flag of an eMode category. When a category is isolated, users with collateral enabled on assets outside the category cannot enter it, and assets outside the category’s collateral bitmap are treated as LTV 0. Added in Aave V3.7.

Input Parameters:

rescueTokens

function rescueTokens(address token, address to, uint256 amount) external virtual override onlyPoolAdmin

Rescue and transfer tokens locked in this contract.

Input Parameters:

eliminateReserveDeficit

function eliminateReserveDeficit(address asset, uint256 amount) external override onlyUmbrella returns (uint256)

Covers the deficit of a specified reserve by burning the equivalent aToken amount for assets with virtual accounting enabled or the equivalent amount of underlying for assets with virtual accounting disabled (e.g. GHO). Only callable by address with onlyUmbrella modifier.

Input Parameters:

Return Values:

View Methods

getUserAccountData

function getUserAccountData(address user) external view virtual override returns (
    uint256 totalCollateralBase,
    uint256 totalDebtBase,
    uint256 availableBorrowsBase,
    uint256 currentLiquidationThreshold,
    uint256 ltv,
    uint256 healthFactor
)

Returns the user account data across all the reserves.

Input Parameters:

Return Values:

getConfiguration

function getConfiguration(address asset) external view virtual override returns (DataTypes.ReserveConfigurationMap memory)

Returns the configuration of the reserve.

Input Parameters:

Return Values:

The DataTypes.ReserveConfigurationMap struct is composed of the following fields:

getUserConfiguration

function getUserConfiguration(address user) external view virtual override returns (DataTypes.UserConfigurationMap memory)

Returns the configuration of the user across all the reserves.

Input Parameters:

Return Values:

The DataTypes.UserConfigurationMap struct is composed of the following fields:

For example, 0x40020 (binary 1000000000000100000) sets bit 5 and bit 18: bit 5 = 3rd reserve used as collateral, bit 18 = 10th reserve borrowed.

getReserveNormalizedIncome

function getReserveNormalizedIncome(address asset) external view virtual override returns (uint256)

Returns the ongoing normalized income for the reserve.

A value of 1e27 means there is no income. As time passes, the yield is accrued. A value of 2*1e27 means for each unit of asset, one unit of income has been accrued.

Input Parameters:

Return Values:

getReserveNormalizedVariableDebt

function getReserveNormalizedVariableDebt(address asset) external view virtual override returns (uint256)

Returns the normalized variable debt per unit of asset.

A value of 1e27 means there is no debt. As time passes, the debt is accrued. A value of 2*1e27 means that for each unit of debt, one unit worth of interest has been accumulated.

Input Parameters:

Return Values:

getReservesList

function getReservesList() external view virtual override returns (address[] memory)

Returns the list of the underlying assets of all the initialized reserves. It does not include dropped reserves.

Return Values:

getReserveAddressById

function getReserveAddressById(uint16 id) external view returns (address)

Returns the address of the underlying asset of a reserve by the reserve id as stored in the DataTypes.ReserveData struct.

Input Parameters:

Return Values:

getEModeCategoryData

function getEModeCategoryData(uint8 id) external view virtual override returns (DataTypes.EModeCategoryLegacy memory)

Returns the data of an eMode category.

Input Parameters:

Return Values:

The DataTypes.EModeCategoryLegacy struct is composed of the following fields:

getIsEModeCategoryIsolated

function getIsEModeCategoryIsolated(uint8 id) external view returns (bool)

Returns whether an eMode category is isolated. Added in Aave V3.7.

Input Parameters:

Return Values:

getReserveData

function getReserveData(address asset) external view virtual override returns (DataTypes.ReserveDataLegacy memory)

Returns the state and configuration of the reserve.

Input Parameters:

Return Values:

The DataTypes.ReserveDataLegacy struct is composed of the following fields:

getUserEMode

function getUserEMode(address user) external view virtual override returns (uint256)

Returns eMode the user is using. 0 is a non eMode category.

Input Parameters:

Return Values:

FLASHLOAN_PREMIUM_TOTAL

function FLASHLOAN_PREMIUM_TOTAL() public view virtual override returns (uint128)

Returns the percent of total flashloan premium paid by the borrower. The whole premium is accrued to the treasury.

Return Values:

FLASHLOAN_PREMIUM_TO_PROTOCOL

function FLASHLOAN_PREMIUM_TO_PROTOCOL() public view virtual override returns (uint128)

Returns the share of the flash loan premium sent to the treasury. Always 100_00 (100%) since Aave V3.4.

Return Values:

MAX_NUMBER_RESERVES

function MAX_NUMBER_RESERVES() public view virtual override returns (uint16)

Returns the maximum number of reserves supported to be listed in this Pool.

Return Values:

getLiquidationGracePeriod

function getLiquidationGracePeriod(address asset) external view virtual override returns (uint40)

Returns the liquidation grace period of the given asset

Input Parameters:

Return Values:

getReserveDeficit

function getReserveDeficit(address asset) external view returns (uint256);

Returns the current deficit of a reserve.

Input Parameters:

Return Values:

getReserveAToken

function getReserveAToken(address asset) external view returns (address);

Returns the aToken address of a reserve.

Input Parameters:

Return Values:

getReserveVariableDebtToken

function getReserveVariableDebtToken(address asset) external view returns (address);

Returns the variableDebtToken address of a reserve.

Input Parameters:

Return Values: