GhoAToken
The implementation of the interest bearing token for the Aave Protocol.
GHO cannot be supplied to the Aave Protocol. However, the GhoAToken is required as it contains logic for GHO to work as a reserve with the Aave Protocol.
The GhoAToken contract inherits the VersionedInitializable, ScaledBalanceTokenBase and EIP712Base contracts, and the IGhoAToken interface.
This page shows the public constant state variables, external write and view methods, and the 'not permitted methods' within the GhoAToken contract. The source code is available on GitHub.
Constant State Variables
The external state variables.
PERMIT_TYPEHASH
bytes32 public constant PERMIT_TYPEHASH =
keccak256('Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)')
ATOKEN_REVISION
uint256 public constant ATOKEN_REVISION = 0x1
Write Methods
initialize
function initialize(
IPool initializingPool,
address treasury,
address underlyingAsset,
IAaveIncentivesController incentivesController,
uint8 aTokenDecimals,
string calldata aTokenName,
string calldata aTokenSymbol,
bytes calldata params
) external override initializer
Initializes the aToken.
Emits the Initialized event.
Input Parameters:
| Name | Type | Description |
|---|---|---|
| initializingPool | IPool | The pool contract that is initializing this contract |
| treasury | address | The address of the Aave treasury, receiving the fees on this aToken |
| underlyingAsset | address | The address of the underlying asset of this aToken, GHO |
| incentivesController | IAaveIncentivesController | The smart contract managing potential incentives distribution |
| aTokenDecimals | uint8 | The decimals of the aToken, same as the underlying asset’s, 18 |
| aTokenName | string | The name of the aToken, ghoAToken |
| aTokenSymbol | string | The symbol of the aToken, GHO |
| params | bytes | A set of encoded parameters for additional initialization |
transferUnderlyingTo
function transferUnderlyingTo(address target, uint256 amount) external virtual override onlyPool
Transfers the underlying asset to target.
It performs a mint of GHO on behalf of the target. Used by the Pool to transfer assets in borrow().
Input Parameters:
| Name | Type | Description |
|---|---|---|
| target | address | The recipient of the underlying token |
| amount | uint256 | The amount getting transferred |
handleRepayment
function handleRepayment(
address user,
address onBehalfOf,
uint256 amount
) external virtual override onlyPool
Handles the underlying received by the aToken after the transfer has been completed.
This function transfers the debt interest repaid by a user to the GHO treasury. It burns all the repaid GHO.
Input Parameters:
| Name | Type | Description |
|---|---|---|
| user | address | The user executing the repayment |
| onBehalfOf | address | The address of the user who will get their debt reduced/removed. |
| amount | uint256 | The amount getting repaid |
distributeFeesToTreasury
function distributeFeesToTreasury() external virtual override
Distribute accumulated fees to the GHO treasury.
Emits the FeesDistributedToTreasury event.
rescueTokens
function rescueTokens(address token, address to, uint256 amount) external override onlyPoolAdmin
Rescues and transfers the tokens locked in this contract to the recipient.
The underlying asset, GHO, cannot be rescued.
Input 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 |
setVariableDebtToken
function setVariableDebtToken(address ghoVariableDebtToken) external override onlyPoolAdmin
Sets a reference to the GHO variable debt token. The variable debt token must not already be set.
Emits the VariableDebtTokenSet event.
Input Parameters:
| Name | Type | Description |
|---|---|---|
| ghoVariableDebtToken | address | The address of the GHOVariableDebtToken |
updateGhoTreasury
function updateGhoTreasury(address newGhoTreasury) external override onlyPoolAdmin
Updates the address of the GHO treasury, where interest earned by the protocol is sent.
Emits the GhoTreasuryUpdated event.
Input Parameters:
| Name | Type | Description |
|---|---|---|
| newGhoTreasury | address | The address of the GhoTreasury |
View Methods
The balanceOf and totalSupply methods, both return zero. The reason is that GHO cannot be supplied to the Aave Protocol. However, the GhoAToken is required as it contains logic for GHO to work as a reserve with the Aave Protocol.
balanceOf
function balanceOf(
address user
) public view virtual override(IncentivizedERC20, IERC20) returns (uint256)
Returns zero at GhoAToken.
Standard ERC20 method.
Input Parameters:
| Name | Type | Description |
|---|---|---|
| user | address | The address of the user |
Return Values:
| Type | Description |
|---|---|
uint256 | 0 |
totalSupply
function totalSupply() public view virtual override(IncentivizedERC20, IERC20) returns (uint256)
Returns zero at GhoAToken.
Standard ERC20 method.
Return Values:
| Type | Description |
|---|---|
uint256 | 0 |
RESERVE_TREASURY_ADDRESS
function RESERVE_TREASURY_ADDRESS() external view override returns (address)
Returns the address of the Aave treasury.
Return Values:
| Type | Description |
|---|---|
address | The address of the Aave treasury |
UNDERLYING_ASSET_ADDRESS
function UNDERLYING_ASSET_ADDRESS() external view override returns (address)
Returns the address of GHO as it is the underlying asset of this aToken.
Return Values:
| Type | Description |
|---|---|
address | The address of the underlying asset, GHO |
DOMAIN_SEPARATOR
function DOMAIN_SEPARATOR() public view override(IAToken, EIP712Base) returns (bytes32)
Overrides the base function to fully implement IAToken.
Gets the domain separator for the token. Return cached value if chainId matches cache, otherwise recomputes separator.
See EIP712Base.DOMAIN_SEPARATOR() for more detailed documentation.
Return Values:
| Type | Description |
|---|---|
bytes32 | The domain separator of the token on the current chain |
nonces
function nonces(address owner) public view override(IAToken, EIP712Base) returns (uint256)
Overrides the base function to fully implement IAToken.
Returns the nonce of the owner.
See EIP712Base.nonces() for more detailed documentation.
Input Parameters:
| Name | Type | Description |
|---|---|---|
| owner | address | The address of the owner |
Return Values:
| Type | Description |
|---|---|
uint256 | The nonce of the owner |
getVariableDebtToken
function getVariableDebtToken() external view override returns (address)
Returns the address of the GHO variable debt token.
Return Values:
| Type | Description |
|---|---|
address | The address of the GhoVariableDebtToken contract |
getGhoTreasury
function getGhoTreasury() external view override returns (address) {
Returns the address of the GHO treasury.
Return Values:
| Type | Description |
|---|---|
address | The address of the GhoTreasury contract |
NOT PERMITTED METHODS
The following methods automatically revert with the error from Aave V3 OPERATION_NOT_SUPPORTED as they are not permitted to be executed.
For example, mint() is not permitted as it is not possible to supply GHO into the pool.
mint
function mint(
address caller,
address onBehalfOf,
uint256 amount,
uint256 index
) external virtual override onlyPool returns (bool)
Not permitted by design.
burn
function burn(
address from,
address receiverOfUnderlying,
uint256 amount,
uint256 index
) external virtual override onlyPool
Not permitted by design.
mintToTreasury
function mintToTreasury(uint256 amount, uint256 index) external virtual override onlyPool
Not permitted by design.
transferOnLiquidation
function transferOnLiquidation(
address from,
address to,
uint256 value
) external virtual override onlyPool
Not permitted by design.
permit
function permit(
address owner,
address spender,
uint256 value,
uint256 deadline,
uint8 v,
bytes32 r,
bytes32 s
) external
Not permitted by design.