Default and Custom

A contract can use either the Default Extension or a Custom Extension.

Default Extension

The default extension has been developed to be used by individual wallets and other hosts that do not require customized methods, features or integrations. It is deployed and cloned through the Factory contract. To use the default extension, clone it with the cloneFarmDefaultExtension function:

function cloneFarmDefaultExtension() public override returns(address clonedExtension) {
    emit ExtensionCloned(clonedExtension = _clone(farmDefaultExtension));
}

The default extension's main functions are:

• Init function

This establishes the three main initial data parameters:

• a boolean value; (true) if the reward token will be minted, (false) if sent from a reserve

• the host address;

• the treasury address

function init(bool byMint, address host, address treasury) public virtual override {

• setHost

This is used to update the extension host.

function setHost(address host) public virtual override hostOnly {

• setTreasury

This is used to update the treasury.

function setTreasury(address treasury) public virtual override hostOnly {

• data

This function returns: the farming contract address deployed; whether the reward tokens are minted or if they come (true) from a reserve (false); the host address; the treasury address; and the reward token address.

function data() view public virtual override returns(address farmMainContract, bool byMint, address host, address treasury, address rewardTokenAddress) {
    return (_farmMainContract, _byMint, _host, _treasury, _rewardTokenAddress);
}

• setFarmingSetups

This is used to create, update or disable the farming setups of a contract.

function setFarmingSetups(FarmingSetupConfiguration[] memory farmingSetups) public virtual override hostOnly {

• transferTo

This allows the extension to transfer reward tokens to the contract. If they will be sent from a reserve, the _safeTransfer function is called to transfer them; if they will be minted, the _mintAndTransfer function is called to first mint and then transfer them. This qualifies a setup for activation.

function transferTo(uint256 amount) public virtual override farmMainOnly {

return _byMint ? _mintAndTransfer(_rewardTokenAddress, _farmMainContract, amount) : _safeTransfer(_rewardTokenAddress, _farmMainContract, amount);

• backToYou

The backToYou function is called in the Farming contract to retrieve reward tokens, in case the amount of reward tokens sent by the extension to the Farming contract is not sufficient to activate the setup(s). See here for more info.

function backToYou(uint256 amount) payable public virtual override farmMainOnly {

• _mintAndTransfer

This calls the classic IERC20 mint method on the passed ERC20 token address.

function _mintAndTransfer(address erc20TokenAddress, address recipient, uint256 value) internal virtual {

• _burn

This calls the classic IERC20 burn method on the passed ERC20 token address.

function _burn(address erc20TokenAddress, uint256 value) internal virtual {

Custom Extension

Custom extensions allow for the integration of Covenant farming contracts with external protocols like DFOs, DAOs, dApps and custom smart contracts. The extension is the de facto integration mode.

For more details, see the Organization-Based Farming Extension Contract section.