CoolerV2Migrator

Inherits: IERC3156FlashBorrower, ICoolerV2Migrator, ReentrancyGuard, Owned, IEnabler

Title: CoolerV2Migrator

A contract that migrates debt from Olympus Cooler V1 facilities to Cooler V2. This is compatible with all three versions of Cooler V1.

This contract uses the IERC3156FlashBorrower interface to interact with Maker flashloans. The debt token of MonoCooler is assumed to be USDS. If that is changed in the future, this contract will need to be re-deployed.

Constants

CHREG

The Clearinghouse registry module

CHREGv1 public immutable CHREG;

DAI

The DAI token

ERC20 public immutable DAI;

USDS

The USDS token

ERC20 public immutable USDS;

GOHM

The gOHM token

ERC20 public immutable GOHM;

MIGRATOR

The DAI <> USDS Migrator

IDaiUsdsMigrator public immutable MIGRATOR;

FLASH

The ERC3156 flash loan provider

IERC3156FlashLender public immutable FLASH;

COOLERV2

The Cooler V2 contract

IMonoCooler public immutable COOLERV2;

MAX_LOANS

This constant is used when iterating through the loans of a Cooler

This is used to prevent infinite loops, and is an appropriate upper bound as the maximum number of loans seen per Cooler is less than 50.

uint8 internal constant MAX_LOANS = type(uint8).max;

State Variables

isEnabled

Whether the contract is enabled

bool public isEnabled;

_COOLER_FACTORIES

The list of CoolerFactories

address[] internal _COOLER_FACTORIES;

Functions

constructor

constructor(
        address owner_,
        address coolerV2_,
        address dai_,
        address usds_,
        address gohm_,
        address migrator_,
        address flash_,
        address chreg_,
        address[] memory coolerFactories_
    ) Owned(owner_);

Parameters

Name	Type	Description
owner_	`address`
coolerV2_	`address`
dai_	`address`
usds_	`address`
gohm_	`address`
migrator_	`address`
flash_	`address`
chreg_	`address`
coolerFactories_	`address[]`

previewConsolidate

Preview the consolidation of a set of loans.

function previewConsolidate(
        address[] memory coolers_
    ) external view onlyEnabled returns (uint256 collateralAmount, uint256 borrowAmount);

Parameters

Name	Type	Description
coolers_	`address[]`	The Coolers to consolidate the loans from.

Returns

Name	Type	Description
collateralAmount	`uint256`	The amount of collateral that will be migrated into Cooler V2.
borrowAmount	`uint256`	The amount of debt that will be borrowed from Cooler V2.

consolidate

Consolidate Cooler V1 loans into Cooler V2

This function supports consolidation of loans from multiple Clearinghouses and Coolers, provided that the caller is the owner.

The funds for paying interest owed and fees will be borrowed from Cooler V2.

It is expected that the caller will have already provided approval for this contract to spend the required tokens. See previewConsolidate() for more details.

This function will revert if:
Any of the Coolers are not owned by the caller.
Any of the Coolers have not been created by the CoolerFactory.
Any of the Coolers have a different lender than an Olympus Clearinghouse.
A duplicate Cooler is provided.
The owner of the destination Cooler V2 has not provided authorization for this contract to manage their Cooler V2 position.
The caller has not approved this contract to spend the collateral token, gOHM.
The contract is not active.
Re-entrancy is detected.

function consolidate(
        address[] memory coolers_,
        address newOwner_,
        IMonoCooler.Authorization memory authorization_,
        IMonoCooler.Signature calldata signature_,
        IDLGTEv1.DelegationRequest[] calldata delegationRequests_
    ) external onlyEnabled nonReentrant;

Parameters

Name	Type	Description
coolers_	`address[]`	The Coolers from which the loans will be migrated.
newOwner_	`address`	Address of the owner of the Cooler V2 position. This can be the same as the caller, or a different address.
authorization_	`IMonoCooler.Authorization`	Authorization parameters for the new owner. Set the `account` field to the zero address to indicate that authorization has already been provided through `IMonoCooler.setAuthorization()`.
signature_	`IMonoCooler.Signature`	Authorization signature for the new owner. Ignored if `authorization_.account` is the zero address.
delegationRequests_	`IDLGTEv1.DelegationRequest[]`	Delegation requests for the new owner.

onFlashLoan

This function reverts if:
The caller is not the flash loan provider
The initiator is not this contract

function onFlashLoan(
        address initiator_,
        address, // flashloan token is only DAI
        uint256 amount_,
        uint256, // lender fee is 0
        bytes calldata params_
    ) external override returns (bytes32);

Parameters

Name	Type	Description
initiator_	`address`	The initiator of the loan.
_	`address`	The loan currency.
amount_	`uint256`	The amount of tokens lent.
_	`uint256`	The additional amount of tokens to repay.
params_	`bytes`	Arbitrary data structure, intended to contain user-defined parameters.

Returns

Name	Type	Description
<none>	`bytes32`	The keccak256 hash of "ERC3156FlashBorrower.onFlashLoan"

_handleRepayments

function _handleRepayments(
        Cooler cooler_,
        ERC20 debtToken_,
        uint256 numLoans_
    ) internal returns (uint256 principal, uint256 interest, uint256 collateral);

Parameters

Name	Type	Description
cooler_	`Cooler`
debtToken_	`ERC20`
numLoans_	`uint256`

Returns

Name	Type	Description
principal	`uint256`
interest	`uint256`
collateral	`uint256`

_getDebtForCooler

function _getDebtForCooler(
        Cooler cooler_,
        address[] memory clearinghouses_
    )
        internal
        view
        returns (
            uint256 coolerPrincipal,
            uint256 coolerInterest,
            uint256 coolerCollateral,
            address debtToken,
            uint8 numLoans
        );

Parameters

Name	Type	Description
cooler_	`Cooler`
clearinghouses_	`address[]`

Returns

Name	Type	Description
coolerPrincipal	`uint256`
coolerInterest	`uint256`
coolerCollateral	`uint256`
debtToken	`address`
numLoans	`uint8`

_isValidCooler

Check if a given cooler was created by the CoolerFactory

function _isValidCooler(address cooler_) internal view returns (bool);

Parameters

Name	Type	Description
cooler_	`address`	Cooler contract

Returns

Name	Type	Description
<none>	`bool`	bool Whether the cooler was created by the CoolerFactory

_inArray

function _inArray(address[] memory array_, address item_) internal pure returns (bool);

Parameters

Name	Type	Description
array_	`address[]`
item_	`address`

Returns

Name	Type	Description
<none>	`bool`

_getClearinghouses

Get all of the clearinghouses in the registry

function _getClearinghouses() internal view returns (address[] memory clearinghouses);

Returns

Name	Type	Description
clearinghouses	`address[]`	The list of clearinghouses

addCoolerFactory

Add a CoolerFactory to the migrator

function addCoolerFactory(address coolerFactory_) external onlyOwner;

Parameters

Name	Type	Description
coolerFactory_	`address`	The CoolerFactory to add

removeCoolerFactory

Remove a CoolerFactory from the migrator

function removeCoolerFactory(address coolerFactory_) external onlyOwner;

Parameters

Name	Type	Description
coolerFactory_	`address`	The CoolerFactory to remove

getCoolerFactories

Get the list of CoolerFactories

function getCoolerFactories() external view returns (address[] memory coolerFactories);

Returns

Name	Type	Description
coolerFactories	`address[]`	The list of CoolerFactories

onlyEnabled

modifier onlyEnabled();

enable

Enables the contract

Implementing contracts should implement permissioning logic

function enable(bytes calldata) external onlyOwner;

Parameters

Name	Type	Description
_	`bytes`	Optional data to pass to a custom enable function

disable

Disables the contract

Implementing contracts should implement permissioning logic

function disable(bytes calldata) external onlyEnabled onlyOwner;

Parameters

Name	Type	Description
_	`bytes`	Optional data to pass to a custom disable function

Structs

CoolerData

Data structure used to store data about a Cooler

struct CoolerData {
        Cooler cooler;
        ERC20 debtToken;
        uint8 numLoans;
    }

Properties

Name	Type	Description
cooler	`Cooler`
debtToken	`ERC20`
numLoans	`uint8`

CoolerTotal

Temporary storage for the principal and interest for each debt token

struct CoolerTotal {
        uint256 daiPrincipal;
        uint256 daiInterest;
        uint256 usdsPrincipal;
        uint256 usdsInterest;
    }

Properties

Name	Type	Description
daiPrincipal	`uint256`
daiInterest	`uint256`
usdsPrincipal	`uint256`
usdsInterest	`uint256`

FlashLoanData

Data structure used for flashloan parameters

struct FlashLoanData {
        CoolerData[] coolers;
        address currentOwner;
        address newOwner;
        uint256 usdsRequired;
        IDLGTEv1.DelegationRequest[] delegationRequests;
    }

Properties

Name	Type	Description
coolers	`CoolerData[]`
currentOwner	`address`
newOwner	`address`
usdsRequired	`uint256`
delegationRequests	`IDLGTEv1.DelegationRequest[]`

CoolerV2Migrator

Constants​

CHREG​

DAI​

USDS​

GOHM​

MIGRATOR​

FLASH​

COOLERV2​

MAX_LOANS​

State Variables​

isEnabled​

_COOLER_FACTORIES​

Functions​

constructor​

previewConsolidate​

consolidate​

onFlashLoan​

_handleRepayments​

_getDebtForCooler​

_isValidCooler​

_inArray​

_getClearinghouses​

addCoolerFactory​

removeCoolerFactory​

getCoolerFactories​

onlyEnabled​

enable​

disable​

Structs​

CoolerData​

CoolerTotal​

FlashLoanData​

Constants

CHREG

DAI

USDS

GOHM

MIGRATOR

FLASH

COOLERV2

MAX_LOANS

State Variables

isEnabled

_COOLER_FACTORIES

Functions

constructor

previewConsolidate

consolidate

onFlashLoan

_handleRepayments

_getDebtForCooler

_isValidCooler

_inArray

_getClearinghouses

addCoolerFactory

removeCoolerFactory

getCoolerFactories

onlyEnabled

enable

disable

Structs

CoolerData

CoolerTotal

FlashLoanData