IChainlinkVRF

Title: IChainlinkVRF

Author: Modified from Chainlink (https://github.com/smartcontractkit/chainlink-evm/blob/develop/contracts/src/v0.8/vrf/VRFConsumerBaseV2Plus.sol)

Interface for the ChainlinkVRF Diamond facet.

This module handles request tracking for Chainlink VRF V2.5 (subscription-funded). The rawFulfillRandomWords entry point is called by the coordinator and manages bookkeeping only; consumer facets that inherit ChainlinkVRF should override it to act on the randomness.

Functions

getConfig

Returns the current VRF configuration.

function getConfig() external view returns (VRFConfig memory);

Returns

Name	Type	Description
<none>	`VRFConfig`

getUserKey

Returns the user key associated with a pending VRF request.

function getUserKey(uint256 vrfRequestId) external view returns (bytes32);

Parameters

Name	Type	Description
vrfRequestId	`uint256`	The coordinator-assigned request ID.

Returns

Name	Type	Description
<none>	`bytes32`	The user-supplied key, or `bytes32(0)` if not found.

setConfig

Sets or replaces the VRF configuration.

Caller must hold DEFAULT_ADMIN_ROLE. Reverts VRFInvalidConfig if coordinator is zero, subscriptionId is zero, or keyHash is zero.

function setConfig(VRFConfig calldata config) external;

Parameters

Name	Type	Description
config	`VRFConfig`	The new VRF configuration.

requestRandomWords

Requests random words from the VRF coordinator.

Caller must hold DEFAULT_ADMIN_ROLE. Stores the userKey against the returned vrfRequestId so the fulfilment callback can look it up.

function requestRandomWords(bytes32 userKey, uint32 numWords) external returns (uint256 vrfRequestId);

Parameters

Name	Type	Description
userKey	`bytes32`	Arbitrary key the caller wants associated with this request.
numWords	`uint32`	Number of random words to request.

Returns

Name	Type	Description
vrfRequestId	`uint256`	The coordinator-assigned request ID.

rawFulfillRandomWords

Called by the VRF coordinator to deliver random words.

Verifies the caller is the configured coordinator, looks up the user key, clears the pending entry, and emits RandomWordsFulfilled. Consumer facets should override this function to consume the randomness.

function rawFulfillRandomWords(uint256 requestId, uint256[] calldata randomWords) external;

Parameters

Name	Type	Description
requestId	`uint256`	The coordinator-assigned request ID.
randomWords	`uint256[]`	The generated random words.

Events

VRFConfigSet

Emitted when the VRF configuration is updated.

event VRFConfigSet(address coordinator, uint256 subscriptionId, bytes32 keyHash);

Parameters

Name	Type	Description
coordinator	`address`	Address of the VRF coordinator.
subscriptionId	`uint256`	Subscription ID funding the requests.
keyHash	`bytes32`	Key hash identifying the oracle's VRF public key.

RandomWordsRequested

Emitted when random words are requested from the coordinator.

event RandomWordsRequested(uint256 indexed vrfRequestId, bytes32 indexed userKey, uint32 numWords);

Parameters

Name	Type	Description
vrfRequestId	`uint256`	The coordinator-assigned request ID.
userKey	`bytes32`	The caller-supplied key associated with this request.
numWords	`uint32`	The number of random words requested.

RandomWordsFulfilled

Emitted when the coordinator fulfils a request.

event RandomWordsFulfilled(uint256 indexed vrfRequestId, bytes32 indexed userKey);

Parameters

Name	Type	Description
vrfRequestId	`uint256`	The coordinator-assigned request ID.
userKey	`bytes32`	The caller-supplied key originally associated with this request.

Errors

VRFNotConfigured

VRF has not been configured (coordinator address is zero).

error VRFNotConfigured();

VRFOnlyCoordinator

rawFulfillRandomWords was called by an address other than the coordinator.

error VRFOnlyCoordinator(address caller);

Parameters

Name	Type	Description
caller	`address`	The unauthorised caller.

VRFRequestNotFound

The given VRF request ID has no pending entry.

error VRFRequestNotFound(uint256 vrfRequestId);

Parameters

Name	Type	Description
vrfRequestId	`uint256`	The unknown request ID.

VRFInvalidConfig

setConfig was called with an invalid configuration (zero coordinator, zero subscription ID, or zero key hash).

error VRFInvalidConfig();

VRFInvalidUserKey

requestRandomWords was called with a zero userKey.

bytes32(0) is the sentinel used by rawFulfillRandomWords to detect a missing pending request. Allowing a zero userKey would make the fulfillment callback indistinguishable from an unknown request ID.

error VRFInvalidUserKey();

Structs

VRFConfig

Full VRF subscription configuration.

struct VRFConfig {
        /// @notice Address of the VRF coordinator.
        address coordinator;
        /// @notice Subscription ID funding requests.
        uint256 subscriptionId;
        /// @notice Key hash identifying the oracle's VRF public key.
        bytes32 keyHash;
        /// @notice Minimum confirmations before the oracle responds.
        uint16 requestConfirmations;
        /// @notice Gas limit for the fulfillment callback.
        uint32 callbackGasLimit;
    }

Properties

Name	Type	Description
coordinator	`address`
subscriptionId	`uint256`
keyHash	`bytes32`
requestConfirmations	`uint16`
callbackGasLimit	`uint32`