Remix Testing ChainLink VRF v2 Direct Funding Method

Question

I'm using ChainLink VRF V2 Direct Funding method to generate random number.

I'm facing problem while generate random number, that my random number request is not getting full-filled after confirming transaction.

// An example of a consumer contract that directly pays for each request.
pragma solidity ^0.8.7;

import "@chainlink/contracts/src/v0.8/ConfirmedOwner.sol";
import "@chainlink/contracts/src/v0.8/VRFV2WrapperConsumerBase.sol";

/**
 * Request testnet LINK and ETH here: https://faucets.chain.link/
 * Find information on LINK Token Contracts and get the latest ETH and LINK faucets here: https://docs.chain.link/docs/link-token-contracts/
 */

/**
 * THIS IS AN EXAMPLE CONTRACT THAT USES HARDCODED VALUES FOR CLARITY.
 * THIS IS AN EXAMPLE CONTRACT THAT USES UN-AUDITED CODE.
 * DO NOT USE THIS CODE IN PRODUCTION.
 */

contract VRFv2DirectFundingConsumer is
    VRFV2WrapperConsumerBase,
    ConfirmedOwner
{
    event RequestSent(uint256 requestId, uint32 numWords);
    event RequestFulfilled(
        uint256 requestId,
        uint256[] randomWords,
        uint256 payment
    );

    struct RequestStatus {
        uint256 paid; // amount paid in link
        bool fulfilled; // whether the request has been successfully fulfilled
        uint256[] randomWords;
    }
    mapping(uint256 => RequestStatus)
        public s_requests; /* requestId --> requestStatus */

    // past requests Id.
    uint256[] public requestIds;
    uint256 public lastRequestId;

    // Depends on the number of requested values that you want sent to the
    // fulfillRandomWords() function. Test and adjust
    // this limit based on the network that you select, the size of the request,
    // and the processing of the callback request in the fulfillRandomWords()
    // function.
    uint32 callbackGasLimit = 100000;

    // The default is 3, but you can set this higher.
    uint16 requestConfirmations = 3;

    // For this example, retrieve 2 random values in one request.
    // Cannot exceed VRFV2Wrapper.getConfig().maxNumWords.
    uint32 numWords = 2;

    // Address LINK - hardcoded for Sepolia
    address linkAddress = 0x779877A7B0D9E8603169DdbD7836e478b4624789;

    // address WRAPPER - hardcoded for Sepolia
    address wrapperAddress = 0xab18414CD93297B0d12ac29E63Ca20f515b3DB46;

    constructor()
        ConfirmedOwner(msg.sender)
        VRFV2WrapperConsumerBase(linkAddress, wrapperAddress)
    {}

    function requestRandomWords()
        external
        onlyOwner
        returns (uint256 requestId)
    {
        requestId = requestRandomness(
            callbackGasLimit,
            requestConfirmations,
            numWords
        );
        s_requests[requestId] = RequestStatus({
            paid: VRF_V2_WRAPPER.calculateRequestPrice(callbackGasLimit),
            randomWords: new uint256[](0),
            fulfilled: false
        });
        requestIds.push(requestId);
        lastRequestId = requestId;
        emit RequestSent(requestId, numWords);
        return requestId;
    }

    function fulfillRandomWords(
        uint256 _requestId,
        uint256[] memory _randomWords
    ) internal override {
        require(s_requests[_requestId].paid > 0, "request not found");
        s_requests[_requestId].fulfilled = true;
        s_requests[_requestId].randomWords = _randomWords;
        emit RequestFulfilled(
            _requestId,
            _randomWords,
            s_requests[_requestId].paid
        );
    }

    function getRequestStatus(
        uint256 _requestId
    )
        external
        view
        returns (uint256 paid, bool fulfilled, uint256[] memory randomWords)
    {
        require(s_requests[_requestId].paid > 0, "request not found");
        RequestStatus memory request = s_requests[_requestId];
        return (request.paid, request.fulfilled, request.randomWords);
    }

    /**
     * Allow withdraw of Link tokens from the contract
     */
    function withdrawLink() public onlyOwner {
        LinkTokenInterface link = LinkTokenInterface(linkAddress);
        require(
            link.transfer(msg.sender, link.balanceOf(address(this))),
            "Unable to transfer"
        );
    }
}

Thanks in Advance

Answer 1

make sure you have enough LINK if you have so the problem is that you have to change the gas limit of your Metamask to 400,000 because remix doesn't calculate it correctly.

Look at this part of the doc. https://i.stack.imgur.com/Ub106.png