wstETHPriceProvider

Overview

License: MIT

contract wstETHPriceProvider is PriceProvider, Initializable, AccessControlUpgradeable

Price provider that uses chainlink

This contract is used to get the price of wstETH in USD.

Events info

GrantModeratorRole

event GrantModeratorRole(address indexed newModerator)

Emitted when the moderator role is granted to a new account.

Parameters:

Name	Type	Description
newModerator	address	The address to which moderator role is granted.

RevokeModeratorRole

event RevokeModeratorRole(address indexed moderator)

Emitted when the moderator role is revoked from an account.

Parameters:

Name	Type	Description
moderator	address	The address from which moderator role is revoked.

SetTokenAndAggregator

event SetTokenAndAggregator(address indexed token, address[] aggregatorPath)

Emitted when the wstETH address and aggregator path are set.

Parameters:

Name	Type	Description
token	address	The address of the wstETH token contract.
aggregatorPath	address[]	The array of aggregator addresses to get the price feed for wstETH in USD.

SetTimeOut

event SetTimeOut(address indexed aggregatorPath, uint256 newTimeOut)

Emitted when the time out for a Chainlink aggregator path is set.

Parameters:

Name	Type	Description
aggregatorPath	address	The address of the Chainlink aggregator path.
newTimeOut	uint256	The new time out value in seconds.

Constants info

MODERATOR_ROLE (0x797669c9)

bytes32 constant MODERATOR_ROLE = keccak256("MODERATOR_ROLE")

DESCRIPTION (0xf1ae8856)

string constant DESCRIPTION = "Price provider that uses chainlink"

MAX_PRICE_PATH_LENGTH (0x01a9a5d3)

uint8 constant MAX_PRICE_PATH_LENGTH = 5

State variables info

usdDecimals (0x66a4b6c0)

uint8 usdDecimals

wstETH (0x4aa07e64)

address wstETH

aggregatorPath (0x004645ff)

address[] aggregatorPath

timeOuts (0x2a6377a9)

mapping(address => uint256) timeOuts

Modifiers info

onlyAdmin

modifier onlyAdmin()

Modifier to restrict access to functions to only the contract admin.

onlyModerator

modifier onlyModerator()

Modifier to restrict access to functions to only the moderator role. The caller must have the moderator role to execute the function.

Functions info

initialize (0x946d9204)

function initialize(
    address _wstETH,
    address[] memory _aggregatorPath
) public initializer

Initializes the wstETH price provider contract with the given wstETH address and aggregator path.

Parameters:

Name	Type	Description
_wstETH	address	The address of the wstETH token contract.
_aggregatorPath	address[]	The array of aggregator addresses to get the price feed for wstETH in USD.

grantModerator (0x6981c7ae)

function grantModerator(address newModerator) public onlyAdmin

Grants the moderator role to a new address.

Parameters:

Name	Type	Description
newModerator	address	The address of the new moderator.

revokeModerator (0x36445636)

function revokeModerator(address moderator) public onlyAdmin

Revokes the moderator role from an address.

Parameters:

Name	Type	Description
moderator	address	The address of the moderator to be revoked.

addAggregatorPath (0xbe04eba7)

function addAggregatorPath(
    address[] memory _aggregatorPath
) public onlyModerator

Adds a new aggregator path for the price oracle.

Requirements:

• Only the moderator can call this function.

• The length of the aggregator path must not exceed MAX_PRICE_PATH_LENGTH.

Parameters:

Name	Type	Description
_aggregatorPath	address[]	The new aggregator path to be added.

setTimeOut (0x60c74154)

function setTimeOut(
    address aggregatorPath_,
    uint256 newTimeOut
) external onlyModerator

Sets the timeout value corresponding to the aggregatorPath.

Example: ETH/USD have a new answer is written when the off-chain data moves more than the 0.5% deviation threshold or 3600 seconds have passed since the last answer was written on-chain. So, the timeOut value for each aggregator will be equal to the heartbeat threshold value plus a period of time to make the transaction update the price, that time period can be 60s or a little more.

Parameters:

Name	Type	Description
aggregatorPath_	address	The address of chainlink aggregator contract.
newTimeOut	uint256	It is the amount of time it takes for a new round of aggregation to start after a specified
amount of time since the last update plus a period of time waiting for new price update transactions to execute.

isActive (0x9f8a13d7)

function isActive(address token) public view override returns (bool)

Checks if the given token is active.

Parameters:

Name	Type	Description
token	address	The address of the token to check.

Return values:

Name	Type	Description
[0]	bool	A boolean indicating whether the token is active or not.

getPriceSTETH (0xcd78d6d4)

function getPriceSTETH() public view returns (uint256 priceMantissa)

Returns the price of stETH in USD.

Return values:

Name	Type	Description
priceMantissa	uint256	The price of stETH in USD as a mantissa value.

getPrice (0x41976e09)

function getPrice(
    address token
) public view override returns (uint256 priceMantissa, uint8 priceDecimals)

Returns the price of the given token in USD.

Parameters:

Name	Type	Description
token	address	The address of the token to get the price for.

Return values:

Name	Type	Description
priceMantissa	uint256	The price of the token in USD, scaled by 1e18.
priceDecimals	uint8	The number of decimals in the USD price.

getEvaluation (0x81fd01ea)

function getEvaluation(
    address token,
    uint256 tokenAmount
) public view override returns (uint256 evaluation)

Returns the evaluation of a given token amount in USD.

Parameters:

Name	Type	Description
token	address	The address of the token to evaluate.
tokenAmount	uint256	The amount of tokens to evaluate.

Return values:

Name	Type	Description
evaluation	uint256	The evaluation of the token amount in USD.

getPriceDecimals (0x1b30aafc)

function getPriceDecimals() public view override returns (uint8)

Returns the number of decimals used for the USD price.

Return values:

Name	Type	Description
[0]	uint8	The number of decimals used for the USD price.

getLatestPrice (0x16345f18)

function getLatestPrice(
    address aggregatorPath_
) public view virtual returns (uint256)

Returns the latest price after performing sanity check and staleness check.

Parameters:

Name	Type	Description
aggregatorPath_	address	The address of chainlink aggregator contract.

Return values:

Name	Type	Description
[0]	uint256	The latest price (answer).