CurveFiAdapter_tricrypto2

Git Source

Extends: BaseAdapter

The CurveFiAdapter_tricrypto2 is designed to interact with the Curve.fi USDT/WBTC/ETH Pool.

This adapter enables users to harness the power of Curve.fi USDT/WBTC/ETH trading capabilities and integrate them into their financial strategies.

Structs

InitializeData

Defines the necessary data for initializing the Adapter.

struct InitializeData {
    address pool;
}

Members

Layout

Used to store crucial data for the Adapter's functionality in a specific storage slot.

struct Layout {
    ICurveFi_tricrypto2 pool;
    address lpToken;
    address[] coins;
}

Members

State Variables

STORAGE_SLOT

Unique identifier for the storage slot where the Layout struct is stored.

bytes32 internal immutable STORAGE_SLOT;

N_COINS

Constant value that defines the number of distinct assets (USDT/WBTC/ETH) that Curve.fi Pool handles.

uint256 private constant N_COINS = 3;

Constructor

Sets the value of the STORAGE_SLOT state variable.

The value is computed as the keccak256 hash of the abi encoding of:

• The Nexera-FI.CurveFiAdapter_tricrypto2 string literal
• The address of this contract (CurveFiAdapter_tricrypto2)

constructor();

Functions

initialize

Initializes the Adapter.

function initialize(bytes calldata initData_) external override;

Parameters

_deposit

Internal function for handling Deposit Operations.

This function is responsible for adding liquidity to the Curve.fi USDT/WBTC/ETH Pool, via invoking the add_liquidity method of the Pool.

Called by executeAction function.

function _deposit(
    IAdapter.TokenAmount[] calldata out,
    IAdapter.TokenAmount[] calldata expectedIn,
    bytes calldata /*extraData*/
) internal override;

Parameters

_withdraw

Internal function for handling Withdraw Operations.

This function is responsible for withdrawing liquidity from the Curve.fi USDT/WBTC/ETH Pool.

Called by executeAction function.

function _withdraw(
    IAdapter.TokenAmount[] calldata out,
    IAdapter.TokenAmount[] calldata expectedIn,
    bytes calldata /*extraData*/
) internal override;

Parameters

_withdrawOne

Helper function for withdrawing liquidity from the Curve.fi USDT/WBTC/ETH Pool when only a single expectedIn token is provided.

This function invokes the remove_liquidity_one_coin method of the Pool.

Called by _withdraw function.

function _withdrawOne(
    IAdapter.TokenAmount[] calldata out,
    IAdapter.TokenAmount[] calldata expectedIn
) private;

Parameters

_withdrawPoolProportions

Helper function for withdrawing liquidity from the Curve.fi USDT/WBTC/ETH Pool when more than a single expectedIn token is provided.

This function invokes the remove_liquidity method of the Pool.

Called by _withdraw function.

function _withdrawPoolProportions(
    IAdapter.TokenAmount[] calldata out,
    IAdapter.TokenAmount[] calldata expectedIn
) private;

Parameters

_swap

Internal function for handling Swap Operations.

This function is responsible for performing single-token swaps within the Curve.fi USDT/WBTC/ETH Pool via invoking the exchange method of the Pool.

function _swap(
    IAdapter.TokenAmount[] calldata out,
    IAdapter.TokenAmount[] calldata expectedIn,
    bytes calldata /*extraData*/
) internal override;

Parameters

_collect

This function always raises the OPERATION_NOT_SUPPORTED error, as Collect is not an action supported within the Curve.fi USDT/WBTC/ETH Pool.

Called by executeAction function.

function _collect(
    IAdapter.TokenAmount[] calldata,
    IAdapter.TokenAmount[] calldata,
    bytes calldata
) internal virtual override;

_operate

This function always raises the OPERATION_NOT_SUPPORTED error, as Operate is not an action supported within the Curve.fi USDT/WBTC/ETH Pool.

Called by executeAction function.

function _operate(
    IAdapter.TokenAmount[] calldata,
    IAdapter.TokenAmount[] calldata,
    bytes calldata 
) internal virtual override;

_approveOutTransfers

Private helper function used to approve token transfers to the the Curve.fi USDT/WBTC/ETH Pool.

Called by the following functions:

• _deposit
• _withdrawOne
• _withdrawPoolProportions
• _swap

function _approveOutTransfers(IAdapter.TokenAmount[] calldata out) private;

Parameters

_fillAmountsArray

Private helper function used to extract the amount values of the provided token compositions.

Called by the following functions:

• _deposit
• _withdrawPoolProportions

function _fillAmountsArray(IAdapter.TokenAmount[] calldata tokenAmounts)
    private
    view
    returns(uint256[N_COINS] memory amounts);

Parameters

Returns

_poolTokenAddreses

Private helper function used to retrieve the addresses of the assets supported within the Curve.fi USDT/WBTC/ETH Pool.

Called by _fillAmountsArray and _findTokenIndex functions.

function _poolTokenAddreses() private view returns(address[N_COINS] memory poolTokens);

Returns

_findTokenIndex

Private helper function used to find the index of a given token within the array of the assets' addresses (USDT, WBTC, ETH) that the _poolTokenAddreses function returns.

Reverts if token is not one of the supported assets : USDT, WBTC, ETH.

Called by withdrawOne and _swap functions.

function _findTokenIndex(address token) private view returns(uint256);

Parameters

Returns

_findAmount

Private helper function responsible for returning the amount associated with a specific token within an array of TokenAmount structures.

Returns 0 if token is not present in the tokenAmounts array.

Called by _fillAmountsArray function.

function _findAmount(IAdapter.TokenAmount[] calldata tokenAmounts, address token)
    private
    pure
    returns(uint256);

Parameters

Returns

layout

Retrieves a reference to the Layout struct stored at a specified storage slot.

function layout() internal view returns (Layout storage l);