chainlink - 如何配置 perform upkeep 以了解在 chainlink keepers 中调用哪个函数？

Question

我希望 Chainlink Keeper 根据一些参数调用一个函数，所以我的 checkUpkeep 函数如下:

function checkUpkeep(
        bytes calldata checkData
    ) external view override returns (
        bool upkeepNeeded, bytes memory performData
    ) {
        if (getPrice() == roundMoonPrice[coinRound]) {
            upkeepNeeded = true;
            return (true, performData) ;`//should perform upkeep for the setTime() function`
        } if (roundWinningIndex[coinRound].length != 0) {
            upkeepNeeded = true;
            return (true, performData);`//should perform upkep for the a withdrawal function
        }

如何配置执行维护以了解调用哪个函数？我如何确保它调用正确的函数？

Answer 1

您可以通过多种方式让管理员调用正确的函数。一种方法是在您的 performData 中添加信息，指定要调用的函数。

performUpkeep 看起来像这样:

function performUpkeep(bytes calldata performData) external override {
        // conditional to call one function
        // conditional to call a different function
    }

1。更好的方式

当 Chainlink 守护者调用 checkUpkeep 时，他们将 performData 的返回信息传递给 performUpkeep 的输入。你可以encode几乎任何东西都可以作为输入传递给 performUpkeep 函数。

例如，您可以将一个数字传递给与要调用的函数相对应的 performUpkeep:

function checkUpkeep(
        bytes calldata checkData
    ) external view override returns (
        bool upkeepNeeded, bytes memory performData
    ) {
        if (getPrice() == roundMoonPrice[coinRound]) {
            upkeepNeeded = true;
            performData = abi.encodePacked(uint256(0); // This is the new line
            return (true, performData) ;
        } if (roundWinningIndex[coinRound].length != 0) {
            upkeepNeeded = true;
            performData = abi.encodePacked(uint256(1); // This is the new line
            return (true, performData);
        }

然后，在您的 performUpkeep 中:

function performUpkeep(bytes calldata performData) external override {
        uint256 decodedValue = abi.decode(performData, (uint256));
        if(decodedValue == 0){
            setTime();
        } 
        if(decodedValue == 1){
            withdraw();
        }
    }

我们编码和解码我们的 performData 对象。事实上，我们也可以使用多个参数以及使用 more clever encoding per the solidity docs.

2。不太好，但更容易理解的方式

否则，如果编码太棘手，您可以对存储变量做一些事情。这并不理想，因为多次调用 performUpkeep 会争夺存储变量。

例如:

uint256 public functionToCall = 0;

function checkUpkeep(
        bytes calldata checkData
    ) external view override returns (
        bool upkeepNeeded, bytes memory performData
    ) {
        if (getPrice() == roundMoonPrice[coinRound]) {
            upkeepNeeded = true;
            functionToCall = 0;
            return (true, performData) ;
        } if (roundWinningIndex[coinRound].length != 0) {
            upkeepNeeded = true;
            functionToCall = 1;
            return (true, performData);
        }

然后:

function performUpkeep(bytes calldata performData) external override {
        if(functionToCall == 0){
            setTime();
        } 
        if(functionToCall == 1){
            withdraw();
        }
    }