AbstractFactory

Git Source

Author: cosimo.demedici.eth (https://github.com/ninfa-labs/ninfa-contracts)

Abstract implementation for clone factory contracts

State Variables

_TOTAL_BPS

uint256 private constant _TOTAL_BPS = 10_000;

_salesFeeRecipient

fee recipient for sales

address private _salesFeeRecipient;

_salesFeeBps

fee fraction for sales fee calculation (e.g. 1000 = 10%)

uint256 private _salesFeeBps;

_mastersWhitelist

whitelisted implementations' addresses; i.e. allowlist of clonable contracts

mapping(address => bool) private _mastersWhitelist;

_clonesDeployed

cloned instances' addresses, needed by external contracts for access control

mapping(address => bool) private _clonesDeployed;

Functions

constructor

The constructor sets the sales fee information.

ownership information must be set in derived contracts.

constructor(uint256 salesFeeBps_, address salesFeeRecipient_);

Parameters

Name	Type	Description
salesFeeBps_	uint256	The numerator of the fee fraction.
salesFeeRecipient_	address	The address to receive the fee.

salesFeeInfo

*sets contract-wide fee information defined as a percentage (of the sale price), in order for self-sovereign contracts to be able to pay a fee to the factory if needed, this allows clones to fetch up to date fee information rather than hardcoding it. e.g. see {ERC1155OpenEdition-mint}, here is an extract:

(bool success, bytes memory returnData) =
FACTORY.call(abi.encodeWithSignature("salesFeeInfo(uint256)", msg.value));
require(success);
(address feeRecipient, uint256 feeAmount) = abi.decode(returnData, (address, uint256));
feeRecipient.sendValue(feeAmount);
```*


```solidity
function salesFeeInfo(uint256 _salePrice) external view returns (address, uint256);

Parameters

Name	Type	Description
_salePrice	uint256	The price of the sale.

exists

Checks if a contract instance exists.

This function may be used by other contracts for access control, i.e. a marketplace like contract using this factory as a source of truth for whitelisted collections.

function exists(address _clone) external view returns (bool);

Parameters

Name	Type	Description
_clone	address	Address of the instance to check.

Returns

Name	Type	Description
<none>	bool	A boolean indicating if the instance exists.

predictDeterministicAddress

Predicts the deterministic address for a given implementation and salt.

function predictDeterministicAddress(address _master, bytes32 _salt) external view returns (address);

Parameters

Name	Type	Description
_master	address	The address of the master implementation.
_salt	bytes32	The salt to use for prediction.

Returns

Name	Type	Description
<none>	address	The predicted address.

_cloneDeterministic

Clone function to create a new instance of a contract.

"Using the same implementation and salt multiple time will revert, since the clones cannot be cloneed twice at the same address." - https://docs.openzeppelin.com/contracts/4.x/api/proxy#Clones-cloneDeterministic-address-bytes32-

Initializes clones upon deployment via a low-level call (more gas-efficient) to invoke the initialize function atomically, because a constructor cannot be used while deploying proxy contracts such as clones.

function _cloneDeterministic(address _master, bytes32 _salt, bytes calldata _data) internal returns (address clone_);

Parameters

Name	Type	Description
_master	address	MUST be one of this factory's whhitelisted collections
_salt	bytes32	_salt is a random number of our choice. generated with https://web3js.readthedocs.io/en/v1.2.11/web3-utils.html#randomhex _salt could also be dynamically calculated in order to avoid duplicate clones and for a way of finding predictable clones if salt the parameters are known, for example: address _clone = erc1155Minter.cloneDeterministic(†bytes32(keccak256(abi.encode(_name, _symbol, _msgSender))));
_data	bytes	The initialization data for the clone. It is the calldata that will be passed to the clone's initialize function.

_setMaster

The function selector is calculated as bytes4(keccak256('initialize(bytes)')) == 0x439fab91

Whitelist or unwhitelist a master implementation.

External visibility because it is meant to be needed by all derived contracts, i.e. no point in having a public getter for it, to avoid extra code.

function _setMaster(address _master, bool _isWhitelisted) internal;

Parameters

Name	Type	Description
_master	address	Address of the master implementation to whitelist.
_isWhitelisted	bool	Bool to set the implementation as whitelisted or not.

_setSalesFeeInfo

see {AbstractFactory-salesFeeInfo}

function _setSalesFeeInfo(address salesFeeRecipient_, uint256 salesFeeBps_) internal;

Parameters

Name	Type	Description
salesFeeRecipient_	address	The address to receive the fee.
salesFeeBps_	uint256	The numerator of the fee fraction.

Events

NewClone

Event emitted when a new clone is created.

event NewClone(address master, address instance, address owner);

Parameters

Name	Type	Description
master	address	The address of the master implementation.
instance	address	The address of the new clone.
owner	address	is needed in order to keep a local database of owners to instance addresses; this avoids keeping track of them on-chain via a mapping.

MastersWhitelistUpdated

Event emitted when a master implementation is updated.

event MastersWhitelistUpdated(address master, bool isWhitelisted);

Parameters

Name	Type	Description
master	address	The address of the master implementation.
isWhitelisted	bool	Bool to set the implementation as whitelisted or not.

SalesFeeInfoUpdated

Event emitted when the sales fee information is updated.

event SalesFeeInfoUpdated(address feeRecipient, uint256 salesFeeBps);

Parameters

Name	Type	Description
feeRecipient	address	The address to receive the fee.
salesFeeBps	uint256	The numerator of the fee fraction.