Cooler
This contract handles the cooldown required before withdrawal of eTokens
For each withdrawal position it mints an NFT. The owner of the NFT is who receives the funds when the withdrawal is executed. The value of the eTokens at the execution time can be higher or lower than the value of the eTokens when the withdrawal was scheduled, due to earnings and losses during the cooldown period. If the resulting amount is lower, the LP (owner of the NFT) will receive less. If the value is higher than the value at the schedule period, the LP will receive ONLY the value at the schedule time, and the difference will be distributed to the remaining LPs of the token.
Types
WithdrawalRequest
Struct to store info about the withdrawal request
There's one of this for each request (each NFT). It contains the request amount and the request time and expiration.
struct WithdrawalRequest {
ETKLib.Scale scaleAtRequest;
contract IEToken etk;
uint128 requestedAmount;
uint40 requestedAt;
uint40 expiration;
}Variables
_withdrawalRequests
mapping(uint256 => struct Cooler.WithdrawalRequest) _withdrawalRequestsMapping with the WithdrawalRequest info
_cooldownPeriods
mapping(contract IEToken => uint40) _cooldownPeriodsMapping with the cooldown period (in seconds) for each eToken
_pendingWithdrawals
mapping(contract IEToken => uint256) _pendingWithdrawalsMapping with the aggregate amount of pending withdrawals per eToken
_nextTokenId
uint256 _nextTokenIdIt used for the withdrawal NFTs, starts at 1.
Events
CooldownPeriodChanged
event CooldownPeriodChanged(contract IEToken eToken, uint40 oldCooldownPeriod, uint40 newCooldownPeriod)Event emitted when the cooldown period is changed
Parameters
| Name | Type | Description |
|---|---|---|
| eToken | contract IEToken | The EToken contract address for which the cooldown period was modified |
| oldCooldownPeriod | uint40 | The previous cooldown period value (in seconds) |
| newCooldownPeriod | uint40 | The new cooldown period value (in seconds) |
WithdrawalRequested
event WithdrawalRequested(contract IEToken eToken, uint256 tokenId, address owner, uint40 when, ETKLib.Scale scaleAtRequest, uint256 amount)Event emitted when a withdrawal is requested
Parameters
| Name | Type | Description |
|---|---|---|
| eToken | contract IEToken | The EToken contract from which the withdrawal is being requested |
| tokenId | uint256 | The NFT id of the withdrawal position created |
| owner | address | The owner initiating the withdrawal request |
| when | uint40 | The timestamp when the withdrawal can be executed |
| scaleAtRequest | ETKLib.Scale | The token scale (see {EToken.getCurrentScale(true)}) at the time of the withdrawal request |
| amount | uint256 | The amount of eTokens being requested for withdrawal |
WithdrawalExecuted
event WithdrawalExecuted(contract IEToken eToken, uint256 tokenId, address receiver, uint256 amountRequested, uint256 amountWithdrawn)Event emitted when a withdrawal is executed
Parameters
| Name | Type | Description |
|---|---|---|
| eToken | contract IEToken | The EToken contract from which the withdrawal was processed |
| tokenId | uint256 | The unique identifier of the token position that was withdrawn |
| receiver | address | The address that received the withdrawn funds |
| amountRequested | uint256 | The original amount of eTokens requested for withdrawal |
| amountWithdrawn | uint256 | The actual amount withdrawn to the receiver |
Errors
WithdrawalRequestEarlierThanMin
error WithdrawalRequestEarlierThanMin(uint40 minRequestTime, uint40 timeRequested)Error produced when requesting a withdrawal earlier than the minimum withdrawal period
InvalidEToken
error InvalidEToken(contract IEToken eToken)Error produced when requesting a withdrawal from an eToken that doesn't have address(this) as cooler
InvalidWithdrawalRequest
error InvalidWithdrawalRequest(uint256 tokenId)Error produced when trying to execute a withdrawal of an non-existent or already used NFT
WithdrawalNotReady
error WithdrawalNotReady(uint256 tokenId, uint40 expiration)Error produced when trying to execute a withdrawal ahead of time (WithdrawalRequest.when)
CannotDoZeroWithdrawals
error CannotDoZeroWithdrawals()Error produced when trying to schedule a withdrawal with zero amount
Public Functions
constructor
constructor(contract IPolicyPool policyPool_) publicinitialize
function initialize(string name_, string symbol_) public virtualInitializes the Cooler contract
Parameters
| Name | Type | Description |
|---|---|---|
| name_ | string | ERC721 name attribute of the NFT collection |
| symbol_ | string | ERC721 symbol attribute of the NFT collection |
supportsInterface
function supportsInterface(bytes4 interfaceId) public view virtual returns (bool)pendingWithdrawals
function pendingWithdrawals(contract IEToken eToken) external view returns (uint256)Returns the amount of pending (scheduled) withdrawals for a given eToken
Parameters
| Name | Type | Description |
|---|---|---|
| eToken | contract IEToken | The eToken (see {EToken}) |
Return Values
| Name | Type | Description |
|---|---|---|
| [0] | uint256 | The amount in currency that is pending |
cooldownPeriod
function cooldownPeriod(contract IEToken eToken, address, uint256) public view returns (uint40)Returns the cooldown period in seconds required for withdrawals in a given eToken
Parameters
| Name | Type | Description |
|---|---|---|
| eToken | contract IEToken | The eToken (see {EToken}) |
| address | ||
| uint256 |
Return Values
| Name | Type | Description |
|---|---|---|
| [0] | uint40 | The cooldown period in seconds |
setCooldownPeriod
function setCooldownPeriod(contract IEToken eToken, uint40 newCooldownPeriod) externalSets the cooldown period for a specific EToken
Parameters
| Name | Type | Description |
|---|---|---|
| eToken | contract IEToken | The EToken contract address to configure the cooldown period for |
| newCooldownPeriod | uint40 | The new cooldown period duration in seconds |
Emits
- CooldownPeriodChanged
- event with the old and new cooldown periods
scheduleWithdrawalWithPermit
function scheduleWithdrawalWithPermit(contract IEToken eToken, uint40 when, uint256 amount, uint256 deadline, uint8 v, bytes32 r, bytes32 s) external returns (uint256 tokenId)Schedules a withdrawal using EIP-2612 permit for gasless approval
This function allows users to schedule withdrawals without prior ERC20 approvals by using EIP-2612 permit signatures for gasless transactions
Parameters
| Name | Type | Description |
|---|---|---|
| eToken | contract IEToken | The EToken contract from which to withdraw |
| when | uint40 | The timestamp when the withdrawal should be executable (when =0 uses the minimum cooldown period) |
| amount | uint256 | The amount of eTokens to withdraw |
| deadline | uint256 | The expiration timestamp for the permit signature |
| v | uint8 | The recovery byte of the signature |
| r | bytes32 | The R component of the signature |
| s | bytes32 | The S component of the signature |
Return Values
| Name | Type | Description |
|---|---|---|
| tokenId | uint256 | The NFT ID of the token representing the withdrawal position |
Emits
- WithdrawalRequested
scheduleWithdrawal
function scheduleWithdrawal(contract IEToken eToken, uint40 when, uint256 amount) external returns (uint256 tokenId)Schedules a withdrawal
Parameters
| Name | Type | Description |
|---|---|---|
| eToken | contract IEToken | The EToken contract from which to withdraw |
| when | uint40 | The timestamp when the withdrawal should be executable (when =0 uses the minimum cooldown period) |
| amount | uint256 | The amount of eTokens to withdraw |
Return Values
| Name | Type | Description |
|---|---|---|
| tokenId | uint256 | The NFT ID of the token representing the withdrawal position |
Emits
- WithdrawalRequested
executeWithdrawal
function executeWithdrawal(uint256 tokenId) externalExecutes a previously scheduled withdrawal after the cooldown period has elapsed
This function processes a withdrawal request that has completed its cooldown period, transferring the underlying tokens to the token owner and cleaning up the withdrawal state.
Parameters
| Name | Type | Description |
|---|---|---|
| tokenId | uint256 | The ID of the token representing the withdrawal position to execute |
Pre-conditions
- The withdrawal request must exist (
request.requestedAt != 0) - The cooldown period must have elapsed (
block.timestamp >= request.expiration)
Emits
- WithdrawalExecuted
- with the requested and actual withdrawn amounts
getCurrentValue
function getCurrentValue(uint256 tokenId) external view returns (uint256)Returns the current withdrawable value for a given withdrawal position
Parameters
| Name | Type | Description |
|---|---|---|
| tokenId | uint256 | The ID of the token representing the withdrawal position |
Return Values
| Name | Type | Description |
|---|---|---|
| [0] | uint256 | The current withdrawable amount in underlying tokens |
getWithdrawalRequestInfo
function getWithdrawalRequestInfo(uint256 tokenId) external view returns (struct Cooler.WithdrawalRequest)Returns the information of a pending withdrawal request
Parameters
| Name | Type | Description |
|---|---|---|
| tokenId | uint256 | The ID of the token representing the withdrawal position |
Return Values
| Name | Type | Description |
|---|---|---|
| [0] | struct Cooler.WithdrawalRequest | The information about the withdrawal request |
Private Functions
__Cooler_init
function __Cooler_init(string name_, string symbol_) internal_scheduleWithdrawal
function _scheduleWithdrawal(contract IEToken eToken, uint40 when, uint256 amount) internal returns (uint256 tokenId)_computeCurrentValue
function _computeCurrentValue(struct Cooler.WithdrawalRequest request) internal view returns (uint256)