Lesson 9: Lottery Smart Contract: Issues with chainlink keepers

[ejim11]

Please I don't know why the chainlink keepers is not looking out for checkUpkeep. Everything returns true but it does not call the perform upkeep

[aaankeet]

@ejim11 Please Provide more info (error and code). So we have a better understanding of you problem.

[ejim11]

These are my checkUpkeep and performUpkeep functions. The code doesn't produce any error. chainlink keepers just fails to check the checkUpkeep function.

function checkUpkeep(
        bytes memory /*checkData*/
    ) public override returns (bool upkeepNeeded, bytes memory /* performData */) {
        bool isOpen = RaffleState.OPEN == s_raffleState;
        bool timePassed = (block.timestamp - s_lastTimeStamp) > i_interval;
        bool hasPlayers = s_players.length > 0;
        bool hasBalance = address(this).balance > 0;
        upkeepNeeded = (isOpen && hasPlayers && hasBalance && timePassed);
        return (upkeepNeeded, "0x0");
    }

    /**
     *@dev This function is called by the chainlink keepers when upkeep is needed
     *
     */
    function performUpkeep(bytes memory /* performData */) external override {
        // request random number
        // Once we get it, do something with it
        // 2 txns process

        (bool upkeepNeeded, ) = checkUpkeep("");

        if (!upkeepNeeded) {
            revert Raffle__UpkeepNotNeeded(
                address(this).balance,
                s_players.length,
                uint256(s_raffleState)
            );
        }

        s_raffleState = RaffleState.CALCULATING;

        uint256 requestId = i_vrfcoordinator.requestRandomWords(
            i_gasLane, //gasLane
            i_subscriptionId,
            REQUEST_CORFIMATIONS,
            i_callbackGasLimit,
            NUM_WORDS
        );

        emit RequestedRaffleWinner(requestId);
    }

This is my deploy script

module.exports = async function ({ getNamedAccounts, deployments }) {
    const { deploy, log } = deployments
    const { deployer } = await getNamedAccounts()

    const chainId = network.config.chainId

    const VRF_SUB_FUND_AMOUNT = ethers.utils.parseEther("40")

    let vrfCoordinatorV2Address, subscriptionId

    if (developmentChains.includes(network.name)) {
        const vrfCoordinatorV2Mock = await ethers.getContract("VRFCoordinatorV2Mock")

        vrfCoordinatorV2Address = vrfCoordinatorV2Mock.address

        const transactionResponse = await vrfCoordinatorV2Mock.createSubscription()

        const transactionReceipt = await transactionResponse.wait(1)

        subscriptionId = transactionReceipt.events[0].args.subId

        // fund subscription
        await vrfCoordinatorV2Mock.fundSubscription(subscriptionId, VRF_SUB_FUND_AMOUNT)
    } else {
        vrfCoordinatorV2Address = networkConfig[chainId]["vrfCoordinatorV2"]

        subscriptionId = networkConfig[chainId]["subscriptionId"]
    }

    const entranceFee = networkConfig[chainId]["entranceFee"]
    const gasLane = networkConfig[chainId]["gasLane"]
    const callbackGasLimit = networkConfig[chainId]["callbackGasLimit"]
    const interval = networkConfig[chainId]["interval"]

    const args = [
        vrfCoordinatorV2Address,
        entranceFee,
        gasLane,
        subscriptionId,
        callbackGasLimit,
        interval,
    ]

    const raffle = await deploy("Raffle", {
        from: deployer,
        args: args,
        log: true,
        waitConfirmations: network.config.blockConfirmations || 1,
    })

    if (!developmentChains.includes(network.name) && process.env.ETHERSCAN_KEY) {
        log("Verifying......")
        await verify(raffle.address, args)
    }

    log("----------------------------")
}

And my hardhat-helper-config file

const networkConfig = {
    11155111: {
        name: "sepolia",
        vrfCoordinatorV2: "0x8103B0A8A00be2DDC778e6e7eaa21791Cd364625",
        entranceFee: ethers.utils.parseEther("0.01"),
        gasLane: "0x474e34a077df58807dbe9c96d3c009b23b3c6d0cce433e59bbf5b34f823bc56c",
        subscriptionId: "2835",
        callbackGasLimit: "500000000",
        interval: 30,
    },
    31337: {
        name: "hardhat",
        entranceFee: ethers.utils.parseEther("0.01"),
        gasLane: "0x474e34a077df58807dbe9c96d3c009b23b3c6d0cce433e59bbf5b34f823bc56c",
        callbackGasLimit: "500000",
        interval: "30",
    },
}

Incase I missed anything, pls you can show me. The contract deploys properly and everything works fine till i enter the raffle and the perform upkeep function is not called which is most likely due to the checkUpkeep not returning upkeepNeeded as true though it passes all the criterea.

thank you.

[aaankeet]

@ejim11 callBackGasLimit is way too high, maximum for sepolia is 2,500,000 change it to 500,000 in your hardhat-helper-config.
and make sure other variables are properly initialized that are being used in request requestRandomWords()

[ejim11]

@aaankeet okay, but it was actually at 500000 before and it didn't work. I put it back and try again tho. Thanks

[aaankeet]

make sure other variables are properly initialized that are being used in request requestRandomWords()
if still doesn't work let me know.

[ejim11]

alright, i will do that

[ejim11]

@aaankeet It finally worked after doing as you told about the callbackGasLimit. Thank you very much.

[aaankeet]

@ejim11 would you mind marking it as answered?