Callable contract's function not exists in ABI

Question

I want to programmatically mint a NFT on Sea Drop on OpenSea.

Here is a sample contract that I deployed to test out mint function Sepolia Etherscan

Here is the mint page OpenSea

If I switch to Write contract tab on Etherscan to directly interact with the smart contract, I can see a mint function listed in ABI, which is called mintSeaDrop, and it takes two arguments (minter and quantity)

With that function, I wrote a simple script to mint that NFT, but the result transaction always gets reverted!

const ethers = require("ethers");

const abi = [
  {
    inputs: [
      { internalType: "address", name: "minter", type: "address" },
      { internalType: "uint256", name: "quantity", type: "uint256" },
    ],
    name: "mintSeaDrop",
    outputs: [],
    stateMutability: "nonpayable",
    type: "function",
  },
];

const ca = "0x3be7fe2ebb70b38d2df12e83e31d8b859a6607a0";
const provider = new ethers.JsonRpcProvider("https://rpc-sepolia.rockx.com");
const wallet = new ethers.Wallet(privateKey, provider);

const contract = new ethers.Contract(ca, abi, wallet);
const minter = wallet.address;
const quantity = 1;

async function mintToken() {
  try {
    const tx = await contract.mintPublic(ca, minter, minter, quantity);
    await tx.wait();
    console.log("Minted token");
  } catch (error) {
    console.error("Error minting token", error);
  }
}

mintToken();

After a while of researching, I found out that when I click mint on OpenSea, MetaMask asks me to confirm to mint the NFT, I switch to Hexdecimal tab to check out, the function that actually gets called is Mint Public, takes 4 parameters (it is not listed in the ABI).

The function Mint Public is in the file ISeaDrop.sol according to Etherscan, but I don't know how to call it from the ABI since it is not listed here.

Is there any advice?

Answer 1

You can get a hint regarding the 4 parameters being passed by decoding a previous transaction, like this:

Here's the revised code with the ABI of the mintPublic function, and passing the parameters while calling the function accordingly:

const ethers = require("ethers");
const privateKey = "PRIVATE_KEY"
const abi = [
    { "inputs": [{ "internalType": "address", "name": "nftContract", "type": "address" }, { "internalType": "address", "name": "feeRecipient", "type": "address" }, { "internalType": "address", "name": "minterIfNotPayer", "type": "address" }, { "internalType": "uint256", "name": "quantity", "type": "uint256" }], "name": "mintPublic", "outputs": [], "stateMutability": "payable", "type": "function" }
];

const seaDropContract = "0x00005EA00Ac477B1030CE78506496e8C2dE24bf5"
const nftContract = "0x3be7fe2ebb70b38d2df12e83e31d8b859a6607a0";
const provider = new ethers.JsonRpcProvider("https://rpc-sepolia.rockx.com");
const wallet = new ethers.Wallet(privateKey, provider);

const contract = new ethers.Contract(seaDropContract, abi, wallet);
const minter = wallet.address;
const feeRecipient = "0x0000a26b00c1F0DF003000390027140000fAa719";
const minterIfNotPayer = ethers.ZeroAddress;
const quantity = 1;

async function mintToken() {
    try {
        const tx = await contract.mintPublic(nftContract, feeRecipient, minterIfNotPayer, quantity);
        const receipt = await tx.wait();
        console.log(`Minted token at ${receipt.hash}`);
    } catch (error) {
        console.error("Error minting token", error);
    }
}

mintToken();

P.S. mintPublic function is inside the SeaDrop contract, not the NFT contract.

---

To push the gas for faster minting of the NFT, you can specify a higher gas price when sending the transaction. This can be done by adding a buffer to the existing gas price, and pass the total value as the gasPrice parameter to the transaction. Here's how you can modify your code to do that:

async function mintToken() {
    try {
        const gasPriceBuffer = ethers.toBigInt(100000000000); // Adjust the buffer as needed
        const gasData = await provider.getFeeData();
        const gasPrice = gasData.gasPrice + gasPriceBuffer;
        const tx = await contract.mintPublic(nftContract, feeRecipient, minterIfNotPayer, quantity, { gasPrice: gasPrice });
        const receipt = await tx.wait();
        console.log(`Minted token at ${receipt.hash}`);
    } catch (error) {
        console.error("Error minting token", error);
    }
}