ICooler

Git Source

Functions

owner

This address owns the collateral in escrow.

function owner() external view returns (address);

collateral

This token is borrowed against.

function collateral() external view returns (IERC20);

debt

This token is lent.

function debt() external view returns (IERC20);

factory

This contract created the Cooler

function factory() external view returns (ICoolerFactory);

requestLoan

Request a loan with given parameters. Collateral is taken at time of request.

function requestLoan(uint256 amount_, uint256 interest_, uint256 loanToCollateral_, uint256 duration_)
    external
    returns (uint256 requestId);

Parameters

Name	Type	Description
amount_	uint256	of debt tokens to borrow.
interest_	uint256	to pay (annualized % of 'amount_'). Expressed in DECIMALS_INTEREST.
loanToCollateral_	uint256	debt tokens per collateral token pledged. Expressed in 10**collateral().decimals().
duration_	uint256	of loan tenure in seconds.

Returns

Name	Type	Description
requestId	uint256	of the created request. Equivalent to the index of request in requests[].

rescindRequest

Cancel a loan request and get the collateral back.

function rescindRequest(uint256 requestId_) external;

Parameters

Name	Type	Description
requestId_	uint256	index of request in requests[].

repayLoan

Repay a loan to get the collateral back.

Despite a malicious lender could reenter with the callback, the usage of msg.sender prevents any economical benefit to the attacker, since they would be repaying the loan themselves.

function repayLoan(uint256 loanId_, uint256 repayment_) external returns (uint256 collateral);

Parameters

Name	Type	Description
loanId_	uint256	index of loan in loans[].
repayment_	uint256	debt tokens to be repaid.

Returns

Name	Type	Description
collateral	uint256	given back to the borrower.

clearRequest

Fill a requested loan as a lender.

function clearRequest(uint256 reqID_, address recipient_, bool isCallback_) external returns (uint256 loanId);

Parameters

Name	Type	Description
reqID_	uint256	index of request in requests[].
recipient_	address	address to repay the loan to.
isCallback_	bool	true if the lender implements the CoolerCallback abstract. False otherwise.

Returns

Name	Type	Description
loanId	uint256	of the granted loan. Equivalent to the index of loan in loans[].

extendLoanTerms

Allow lender to extend a loan for the borrower. Doesn't require borrower permission because it doesn't have a negative impact for them.

Since this function solely impacts the expiration day, the lender should ensure that extension interest payments are done beforehand.

function extendLoanTerms(uint256 loanId_, uint8 times_) external;

Parameters

Name	Type	Description
loanId_	uint256	index of loan in loans[].
times_	uint8	that the fixed-term loan duration is extended.

claimDefaulted

Claim collateral upon loan default.

function claimDefaulted(uint256 loanID_)
    external
    returns (uint256 principal, uint256 interestDue, uint256 collateral, uint256 elapsed);

Parameters

Name	Type	Description
loanID_	uint256	index of loan in loans[].

Returns

Name	Type	Description
principal	uint256	defaulted debt by the borrower.
interestDue	uint256	collateral kept by the lender.
collateral	uint256	elapsed time since expiry.
elapsed	uint256	elapsed time since expiry.

collateralFor

Compute collateral needed for a desired loan amount at given loan to collateral ratio.

function collateralFor(uint256 principal_, uint256 loanToCollateral_) external view returns (uint256 collateral);

Parameters

Name	Type	Description
principal_	uint256	amount of debt tokens.
loanToCollateral_	uint256	ratio for loan. Expressed in 10**collateral().decimals().

Returns

Name	Type	Description
collateral	uint256	amount of collateral tokens required for the loan.

interestFor

Compute interest cost on amount for duration at given annualized rate.

function interestFor(uint256 principal_, uint256 rate_, uint256 duration_) external view returns (uint256 interest);

Parameters

Name	Type	Description
principal_	uint256	amount of debt tokens.
rate_	uint256	of interest (annualized).
duration_	uint256	of the loan in seconds.

Returns

Name	Type	Description
interest	uint256	in debt token terms.

hasExpired

Check if given loan has expired.

function hasExpired(uint256 loanID_) external view returns (bool);

Parameters

Name	Type	Description
loanID_	uint256	index of loan in loans[].

Returns

Name	Type	Description
<none>	bool	Expiration status.

isActive

Check if a given request is active.

function isActive(uint256 reqID_) external view returns (bool);

Parameters

Name	Type	Description
reqID_	uint256	index of request in requests[].

Returns

Name	Type	Description
<none>	bool	Active status.

getRequest

Getter for Request data as a struct.

function getRequest(uint256 reqID_) external view returns (Request memory);

Parameters

Name	Type	Description
reqID_	uint256	index of request in requests[].

Returns

Name	Type	Description
<none>	Request	Request struct.

getLoan

Getter for Loan data as a struct.

function getLoan(uint256 loanID_) external view returns (Loan memory);

Parameters

Name	Type	Description
loanID_	uint256	index of loan in loans[].

Returns

Name	Type	Description
<none>	Loan	Loan struct.

Errors

OnlyApproved

error OnlyApproved();

Deactivated

error Deactivated();

Default

error Default();

NotExpired

error NotExpired();

NotCoolerCallback

error NotCoolerCallback();

Structs

Request

A loan begins with a borrow request.

struct Request {
    uint256 amount; // Amount to be borrowed.
    uint256 interest; // Annualized percentage to be paid as interest.
    uint256 loanToCollateral; // Requested loan-to-collateral ratio.
    uint256 duration; // Time to repay the loan before it defaults.
    bool active; // Any lender can clear an active loan request.
    address requester; // The address that created the request.
}

Loan

A request is converted to a loan when a lender clears it.

struct Loan {
    Request request; // Loan terms specified in the request.
    uint256 principal; // Amount of principal debt owed to the lender.
    uint256 interestDue; // Interest owed to the lender.
    uint256 collateral; // Amount of collateral pledged.
    uint256 expiry; // Time when the loan defaults.
    address lender; // Lender's address.
    address recipient; // Recipient of repayments.
    bool callback; // If this is true, the lender must inherit CoolerCallback.
}