Chainlink VRF API Reference [v1]

API reference for VRFConsumerBase.

Index

Constructors

| Name | Description | | --------------------------- | ----------------------------------- | | constructor | Initialize your consuming contract. |

Functions

| Name | Description | | --------------------------------------- | ------------------------------------------------------------ | | requestRandomness | Make a request to the VRFCoordinator. | | fulfillRandomness | Called by VRFCoordinator when it receives a valid VRF proof. |

Constructor

Initialize your consuming contract.

constructor(address _vrfCoordinator, address _link)

• _vrfCoordinator: Address of the Chainlink VRF Coordinator. See Chainlink VRF Addresses for details.
• _link: Address of the LINK token. See LINK Token Addresses for details.

Note: _seed has recently been deprecated.

Functions

requestRandomness

Make a request to the VRF coordinator.

function requestRandomness(bytes32 _keyHash, uint256 _fee)
    public returns (bytes32 requestId)

• _keyHash: The public key against which randomness is generated. See Chainlink VRF supported networks for details.
• _fee: The fee, in LINK, for the request. Specified by the oracle.
• RETURN: The ID unique to a single request.

fulfillRandomness

Called by VRFCoordinator when it receives a valid VRF proof. Override this function to act upon the random number generated by Chainlink VRF.

function fulfillRandomness(bytes32 requestId, uint256 randomness)
    internal virtual;

• requestId: The ID initially returned by requestRandomness.
• randomness: The random number generated by Chainlink VRF.

Reference

Maximizing security

Chainlink VRF provides powerful security guarantees and is easy to integrate. However, smart contract security is a nuanced topic. You can read about the top security considerations for VRF.