GhoFlashMinter

This contract enables FlashMinting of GHO. It is based heavily on the EIP3156 reference implementation.

The GhoFlashMinter contract inherits the IGhoFlashMinter interface.

This page shows the public constant and immutable state variables, and external write and view methods within the GhoFlashMinter contract. The source code is available on GitHub.

Constant State Variables

CALLBACK_SUCCESS

bytes32 public constant CALLBACK_SUCCESS = keccak256('ERC3156FlashBorrower.onFlashLoan')

Hash of the ERC3156FlashBorrower.onFlashLoan that must be returned by the onFlashLoan callback.

MAX_FEE

  uint256 public constant MAX_FEE = 1e4

The maximum percentage fee of the FlashMinted amount that the flashFee can be set to (in bps).

Immutable State Variables

ADDRESSES_PROVIDER

IPoolAddressesProvider public immutable override ADDRESSES_PROVIDER

The address of the PoolAddressesProvider.

GHO_TOKEN

IGhoToken public immutable GHO_TOKEN

The address of the GhoToken.

Write Methods

flashLoan

function flashLoan(
    IERC3156FlashBorrower receiver,
    address token,
    uint256 amount,
    bytes calldata data
) external override returns (bool)

Initiates a FlashMint. GHO is the only supported token.

From the IERC3156FlashLender interface.

Emits the FlashMint event.

Input Parameters:

Name	Type	Description
receiver	IERC3156FlashBorrower	The receiver of the tokens in the loan, and the receiver of the callback
token	address	The loan currency. Only GHO is supported
amount	uint256	The amount of tokens to FlashMint
data	bytes	Arbitrary data structure, intended to contain user-defined parameters

Return Values:

Type	Description
bool	Returns true if the operation was successful. If failed, reverts.

distributeFeesToTreasury

function distributeFeesToTreasury() external override

Distribute accumulated fees to the GHO treasury.

Emits the FeesDistributedToTreasury event.

updateFee

function updateFee(uint256 newFee) external override onlyPoolAdmin

Updates the percentage fee. It is the percentage of the flash-minted amount that needs to be repaid. The fee is expressed in bps. A value of 100, results in 1.00%.

The newFee must be less than the MAX_FEE.

Emits the FeeUpdated event.

Input Parameters:

Name	Type	Description
newFee	uint256	The new percentage fee (in bps)

updateGhoTreasury

function updateGhoTreasury(address newGhoTreasury) external override onlyPoolAdmin

Updates the address of the GHO treasury, where FlashMint fees are sent.

Emits the GhoTreasuryUpdated event.

Input Parameters:

Name	Type	Description
newGhoTreasury	address	The address of the GhoTreasury

View Methods

maxFlashLoan

function maxFlashLoan(address token) external view override returns (uint256)

The amount of currency available to be FlashMinted. GHO is the only supported token. Returns 0 if any other address other than GHO is passed.

From the IERC3156FlashLender interface.

Input Parameters:

Name	Type	Description
token	address	The loan currency (GHO)

Return Values:

Type	Description
uint256	The amount of token that can be FlashMinted.

flashFee

function flashFee(address token, uint256 amount) external view override returns (uint256)

The fee to be charged for a given loan. GHO is the only supported token.

From the IERC3156FlashLender interface.

Input Parameters:

Name	Type	Description
token	address	The loan currency
amount	uint256	The amount of tokens lent

Return Values:

Type	Description
uint256	The amount of token to be charged for the loan, on top of the returned principal

getFee

function getFee() external view override returns (uint256)

Returns the percentage of each flash mint taken as a fee.

Return Values:

Type	Description
uint256	The percentage fee of the FlashMinted amount that needs to be repaid, on top of the principal (in bps)

getGhoTreasury

function getGhoTreasury() external view override returns (address)

Returns the address of the GHO treasury, the recipient of fee distributions.

Return Values:

Type	Description
address	The address of the GhoTreasury contract