Pool Contract Interface

Main point of interaction with Bend.

Users can:

• Supply
• Withdraw
• Borrow
• Repay
• Enable/disable their supplied assets as collateral rebalance stable rate borrow positions
• Liquidate positions

supply

Supplies an amount of underlying asset into the reserve, receiving in return overlying aTokens.

• E.g. User supplies 100 $HONEY and gets in return 100 a$HONEY

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

Parameters

Name	Type	Description
asset	address	The address of the underlying asset to supply
amount	uint256	The amount to be supplied
onBehalfOf	address	The address that will receive the aTokens, same as msg.sender if the user wants to receive them on his own wallet, or a different address if the beneficiary of aTokens is a different wallet
referralCode	uint16	Code used to register the integrator originating the operation, for potential rewards. 0 if the action is executed directly by the user, without any middle-man

supplyWithPermit

Supply with transfer approval of asset to be supplied done via permit function see: https://eips.ethereum.org/EIPS/eip-2612 and https://eips.ethereum.org/EIPS/eip-713

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

Parameters

Name	Type	Description
asset	address	The address of the underlying asset to supply
amount	uint256	The amount to be supplied
onBehalfOf	address	The address that will receive the aTokens, same as msg.sender if the user wants to receive them on his own wallet, or a different address if the beneficiary of aTokens is a different wallet
referralCode	uint16	Code used to register the integrator originating the operation, for potential rewards. 0 if the action is executed directly by the user, without any middle-man
deadline	uint256	The deadline timestamp that the permit is valid
permitV	uint8	The V parameter of ERC712 permit sig
permitR	bytes32	The R parameter of ERC712 permit sig
permitS	bytes32	The S parameter of ERC712 permit sig

withdraw

Withdraws an amount of underlying asset from the reserve, burning the equivalent aTokens owned E.g. User has 100 a$HONEY, calls withdraw() and receives 100 $HONEY, burning the 100 $aHONEY

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

Parameters

Name	Type	Description
asset	address	The address of the underlying asset to withdraw
amount	uint256	The underlying amount to be withdrawn - Send the value type(uint256).max in order to withdraw the whole aToken balance
to	address	The address that will receive the underlying, same as msg.sender if the user wants to receive it on his own wallet, or a different address if the beneficiary is a different wallet

Returns

Name	Type	Description
<none>	uint256	The final amount withdrawn

borrow

Allows users to borrow a specific amount of the reserve underlying asset, provided that the borrower already supplied enough collateral, or he was given enough allowance by a credit delegator on the corresponding debt token (StableDebtToken or VariableDebtToken)

• E.g. User borrows 100 $HONEY passing as onBehalfOf his own address, receiving the 100 $HONEY in his wallet and 100 stable/variable debt tokens, depending on the interestRateMode

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

Parameters

Name	Type	Description
asset	address	The address of the underlying asset to borrow
amount	uint256	The amount to be borrowed
interestRateMode	uint256	The interest rate mode at which the user wants to borrow: 1 for Stable, 2 for Variable
referralCode	uint16	The code used to register the integrator originating the operation, for potential rewards. 0 if the action is executed directly by the user, without any middle-man
onBehalfOf	address	The address of the user who will receive the debt. Should be the address of the borrower itself calling the function if he wants to borrow against his own collateral, or the address of the credit delegator if he has been given credit delegation allowance

repay

Repays a borrowed amount on a specific reserve, burning the equivalent debt tokens owned

• E.g. User repays 100 $HONEY, burning 100 variable/stable debt tokens of the onBehalfOf address

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

Parameters

Name	Type	Description
asset	address	The address of the borrowed underlying asset previously borrowed
amount	uint256	The amount to repay - Send the value type(uint256).max in order to repay the whole debt for asset on the specific debtMode
interestRateMode	uint256	The interest rate mode at of the debt the user wants to repay: 1 for Stable, 2 for Variable
onBehalfOf	address	The address of the user who will get his debt reduced/removed. Should be the address of the user calling the function if he wants to reduce/remove his own debt, or the address of any other borrower whose debt should be removed

Returns

Name	Type	Description
<none>	uint256	The final amount repaid

repayWithPermit

Repay with transfer approval of asset to be repaid done via permit function see: https://eips.ethereum.org/EIPS/eip-2612 and https://eips.ethereum.org/EIPS/eip-713

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

Parameters

Name	Type	Description
asset	address	The address of the borrowed underlying asset previously borrowed
amount	uint256	The amount to repay - Send the value type(uint256).max in order to repay the whole debt for asset on the specific debtMode
interestRateMode	uint256	The interest rate mode at of the debt the user wants to repay: 1 for Stable, 2 for Variable
onBehalfOf	address	Address of the user who will get his debt reduced/removed. Should be the address of the user calling the function if he wants to reduce/remove his own debt, or the address of any other borrower whose debt should be removed
deadline	uint256	The deadline timestamp that the permit is valid
permitV	uint8	The V parameter of ERC712 permit sig
permitR	bytes32	The R parameter of ERC712 permit sig
permitS	bytes32	The S parameter of ERC712 permit sig

Returns

Name	Type	Description
<none>	uint256	The final amount repaid

repayWithATokens

Repays a borrowed amount on a specific reserve using the reserve aTokens, burning the equivalent debt tokens

• E.g. User repays 100 $HONEY using 100 a$HONEY, burning 100 variable/stable debt tokens

Passing uint256.max as amount will clean up any residual aToken dust balance, if the user aToken balance is not enough to cover the whole debt

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

Parameters

Name	Type	Description
asset	address	The address of the borrowed underlying asset previously borrowed
amount	uint256	The amount to repay - Send the value type(uint256).max in order to repay the whole debt for asset on the specific debtMode
interestRateMode	uint256	The interest rate mode at of the debt the user wants to repay: 1 for Stable, 2 for Variable

Returns

Name	Type	Description
<none>	uint256	The final amount repaid

setUserUseReserveAsCollateral

Allows suppliers to enable/disable a specific supplied asset as collateral

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

Parameters

Name	Type	Description
asset	address	The address of the underlying asset supplied
useAsCollateral	bool	True if the user wants to use the supply as collateral, false otherwise

liquidationCall

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

• The caller (liquidator) covers debtToCover amount of debt of the user getting liquidated, and receives a proportionally amount of the collateralAsset plus a bonus to cover market risk

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

Parameters

Name	Type	Description
collateralAsset	address	The address of the underlying asset used as collateral, to receive as result of the liquidation
debtAsset	address	The address of the underlying borrowed asset to be repaid with the liquidation
user	address	The address of the borrower getting liquidated
debtToCover	uint256	The debt amount of borrowed asset the liquidator wants to cover
receiveAToken	bool	True if the liquidators wants to receive the collateral aTokens, false if he wants to receive the underlying collateral asset directly

getReserveData

Returns the state and configuration of the reserve

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

Parameters

Name	Type	Description
asset	address	The address of the underlying asset of the reserve

Returns

Name	Type	Description
<none>	DataTypes.ReserveData	The state and configuration data of the reserve

getUserAccountData

Returns the user account data across all the reserves

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

Parameters

Name	Type	Description
user	address	The address of the user

Returns

Name	Type	Description
totalCollateralBase	uint256	The total collateral of the user in the base currency used by the price feed
totalDebtBase	uint256	The total debt of the user in the base currency used by the price feed
availableBorrowsBase	uint256	The borrowing power left of the user in the base currency used by the price feed
currentLiquidationThreshold	uint256	The liquidation threshold of the user
ltv	uint256	The loan to value of The user
healthFactor	uint256	The current health factor of the user

getConfiguration

Returns the configuration of the reserve

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

Parameters

Name	Type	Description
asset	address	The address of the underlying asset of the reserve

Returns

Name	Type	Description
<none>	DataTypes.ReserveConfigurationMap	The configuration of the reserve

getUserConfiguration

Returns the configuration of the user across all the reserves

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

Parameters

Name	Type	Description
user	address	The user address

Returns

Name	Type	Description
<none>	DataTypes.UserConfigurationMap	The configuration of the user

getReserveNormalizedIncome

Returns the normalized income of the reserve

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

Parameters

Name	Type	Description
asset	address	The address of the underlying asset of the reserve

Returns

Name	Type	Description
<none>	uint256	The reserve's normalized income

getReserveNormalizedVariableDebt

Returns the normalized variable debt per unit of asset

WARNING: This function is intended to be used primarily by the protocol itself to get a "dynamic" variable index based on time, current stored index and virtual rate at the current moment (approx. a borrower would get if opening a position). This means that is always used in combination with variable debt supply/balances. If using this function externally, consider that is possible to have an increasing normalized variable debt that is not equivalent to how the variable debt index would be updated in storage (e.g. only updates with non-zero variable debt supply)

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

Parameters

Name	Type	Description
asset	address	The address of the underlying asset of the reserve

Returns

Name	Type	Description
<none>	uint256	The reserve normalized variable debt

getReservesList

Returns the list of the underlying assets of all the initialized reserves

It does not include dropped reserves

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

Returns

Name	Type	Description
<none>	address[]	The addresses of the underlying assets of the initialized reserves

getReserveAddressById

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

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

Parameters

Name	Type	Description
id	uint16	The id of the reserve as stored in the DataTypes.ReserveData struct

Returns

Name	Type	Description
<none>	address	The address of the reserve associated with id

MAX_STABLE_RATE_BORROW_SIZE_PERCENT

Returns the percentage of available liquidity that can be borrowed at once at stable rate

function MAX_STABLE_RATE_BORROW_SIZE_PERCENT() public view virtual override returns (uint256);

Returns

Name	Type	Description
<none>	uint256	The percentage of available liquidity to borrow, expressed in bps

MAX_NUMBER_RESERVES

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

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

Returns

Name	Type	Description
<none>	uint16	The maximum number of reserves supported

finalizeTransfer

Validates and finalizes an aToken transfer

Only callable by the overlying aToken of the asset

function finalizeTransfer(
    address asset,
    address from,
    address to,
    uint256 amount,
    uint256 balanceFromBefore,
    uint256 balanceToBefore
) external virtual override;

Parameters

Name	Type	Description
asset	address	The address of the underlying asset of the aToken
from	address	The user from which the aTokens are transferred
to	address	The user receiving the aTokens
amount	uint256	The amount being transferred/withdrawn
balanceFromBefore	uint256	The aToken balance of the from user before the transfer
balanceToBefore	uint256	The aToken balance of the to user before the transfer

initReserve

Initializes a reserve, activating it, assigning an aToken and debt tokens and an interest rate strategy

Only callable by the PoolConfigurator contract

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

Parameters

Name	Type	Description
asset	address	The address of the underlying asset of the reserve
aTokenAddress	address	The address of the aToken that will be assigned to the reserve
stableDebtAddress	address	The address of the StableDebtToken that will be assigned to the reserve
variableDebtAddress	address	The address of the VariableDebtToken that will be assigned to the reserve
interestRateStrategyAddress	address	The address of the interest rate strategy contract

dropReserve

Drop a reserve

Only callable by the PoolConfigurator contract

function dropReserve(address asset) external virtual override onlyPoolConfigurator;

Parameters

Name	Type	Description
asset	address	The address of the underlying asset of the reserve

setConfiguration

Sets the configuration bitmap of the reserve as a whole

Only callable by the PoolConfigurator contract

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

Parameters

Name	Type	Description
asset	address	The address of the underlying asset of the reserve
configuration	DataTypes.ReserveConfigurationMap	The new configuration bitmap

rescueTokens

Rescue and transfer tokens locked in this contract

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

Parameters

Name	Type	Description
token	address	The address of the token
to	address	The address of the recipient
amount	uint256	The amount of token to transfer

deposit

Supplies an amount of underlying asset into the reserve, receiving in return overlying aTokens.

• E.g. User supplies 100 $HONEY and gets in return 100 a$HONEY

Deprecated: maintained for compatibility purposes

function deposit(address asset, uint256 amount, address onBehalfOf, uint16 referralCode) external virtual override;

Parameters

Name	Type	Description
asset	address	The address of the underlying asset to supply
amount	uint256	The amount to be supplied
onBehalfOf	address	The address that will receive the aTokens, same as msg.sender if the user wants to receive them on his own wallet, or a different address if the beneficiary of aTokens is a different wallet
referralCode	uint16	Code used to register the integrator originating the operation, for potential rewards. 0 if the action is executed directly by the user, without any middle-man

mintToPOLFeeCollector

function mintToPOLFeeCollector(address[] assets) external virtual

Mints the assets accrued through the reserve factor to the POL fee collector in the form of aTokens

Parameters

Name	Type	Description
assets	address[]	The list of reserves for which the minting needs to be executed