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RafflFactory

Git Source

Inherits: AutomationCompatibleInterface, VRFConsumerBaseV2Plus, FactoryFeeManager

Author: JA (@ubinatus)

Raffl is a decentralized platform built on the Ethereum blockchain, allowing users to create and participate in raffles/lotteries with complete transparency, security, and fairness.

The RafflFactory contract can be used to create raffle contracts, leveraging Chainlink VRF and Chainlink Automations.

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State Variables

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keyHash

Max gas to bump to

bytes32 keyHash;

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callbackGasLimit

Callback gas limit for the Chainlink VRF

uint32 callbackGasLimit = 500_000;

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requestConfirmations

Number of requests confirmations for the Chainlink VRF

uint16 requestConfirmations = 3;

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subscriptionId

Chainlink subscription ID

uint256 public subscriptionId;

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implementation

The address that will be used as a delegate call target for Raffls.

address public immutable implementation;

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_salt

It will be used as the salt for create2

bytes32 internal _salt;

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_raffles

Maps the created Raffls addresses

mapping(address => bool) internal _raffles;

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_requestIds

Maps the VRF requestId to the Raffls address

mapping(uint256 => address) internal _requestIds;

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_activeRaffles

Stores the active raffles, which upkeep is pending to be performed

ActiveRaffle[] internal _activeRaffles;

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Functions

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constructor

*Creates a Raffl factory contract. Requirements:

• implementationAddress has to be a contract.
• feeCollectorAddress can’t be address 0x0.
• poolFeePercentage must be within 0 and maxFee range.
• vrfCoordinator can’t be address 0x0.*

constructor(
    address implementationAddress,
    address feeCollectorAddress,
    uint64 creationFeeValue,
    uint64 poolFeePercentage,
    address vrfCoordinator,
    bytes32 _keyHash,
    uint256 _subscriptionId
)
    VRFConsumerBaseV2Plus(vrfCoordinator);

Parameters

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nextSalt

Increments the salt one step.

function nextSalt() public;

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createRaffle

Creates new Raffl contracts. Requirements:

• underlyingTokenAddress cannot be the zero address.
• timestamps must be given in ascending order.
• percentages must be given in ascending order and the last one must always be 1 eth, where 1 eth equals to 100%.

function createRaffle(
    address entryToken,
    uint256 entryPrice,
    uint256 minEntries,
    uint256 deadline,
    IRaffl.Prize[] calldata prizes,
    IRaffl.TokenGate[] calldata tokenGates,
    IRaffl.ExtraRecipient calldata extraRecipient
)
    external
    payable
    returns (address raffle);

Parameters

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activeRaffles

Exposes the ActiveRaffles

function activeRaffles() public view returns (ActiveRaffle[] memory);

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handleSubscription

Sets the Chainlink VRF subscription settings

function handleSubscription(
    uint64 _subscriptionId,
    bytes32 _keyHash,
    uint32 _callbackGasLimit,
    uint16 _requestConfirmations
)
    external
    onlyOwner;

Parameters

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checkUpkeep

Method called by the Chainlink Automation Nodes to check if performUpkeep must be done.

Performs the computation to the array of _activeRaffles. This opens the possibility of having several checkUpkeeps done at the same time.

function checkUpkeep(bytes calldata checkData)
    external
    view
    override
    returns (bool upkeepNeeded, bytes memory performData);

Parameters

Returns

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performUpkeep

Permissionless write method usually called by the Chainlink Automation Nodes.

Either starts the draw for a raffle or cancels the raffle if criteria is not met.

function performUpkeep(bytes calldata performData) external override;

Parameters

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fulfillRandomWords

Method called by the Chainlink VRF Coordinator

function fulfillRandomWords(uint256 requestId, uint256[] memory randomWords) internal override;

Parameters

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_burnActiveRaffle

Helper function to remove a raffle from the _activeRaffles array

Move the last element to the deleted stop and removes the last element

function _burnActiveRaffle(uint256 i) internal;

Parameters

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setFeeCollector

FUNCTIONS

*Set address of fee collector. Requirements:

• msg.sender has to be the owner of the factory.
• newFeeCollector can’t be address 0x0.*

function setFeeCollector(address newFeeCollector) external override onlyOwner;

Parameters

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Events

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RaffleCreated

event RaffleCreated(address raffle);

Parameters

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Structs

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ActiveRaffle

raffle the address of the raffle

deadline is the timestamp that marks the start time to perform the upkeep effect.

struct ActiveRaffle {
    address raffle;
    uint256 deadline;
}