Mintar com viem

Minte NFTs na Chiliz Chain programaticamente usando TypeScript com viem ou ethers.js, um contrato ERC-721 implantado no Remix e Pinata para hospedagem IPFS.

Para desenvolvedores que preferem controle granular sobre o processo de mintagem, você pode usar TypeScript vanilla com viem, uma interface TypeScript para projetos baseados em EVM. A biblioteca Ethers.js também é uma abordagem robusta.

Usar vanilla requer um pouco mais de trabalho do que quando se usa frameworks como o thirdweb. Por exemplo, a menos que você execute seu próprio nó IPFS, precisará usar plataformas de armazenamento de NFT, que são pagas.

Este exemplo usa Pinata como host IPFS. Você também precisará implantar um contrato OpenZeppelin ERC-721 na Chiliz Chain por conta própria. O Remix IDE oferece um IDE no navegador para isso. Não se esqueça de verificar o contrato usando um block explorer!

Agora, vamos instalar o viem, o Pinata SDK e o módulo dotenv:

npm i viem pinata dotenv

Configure seu arquivo .env para funcionar com suas necessidades:

# Wallet / contract
PRIVATE_KEY=0xabc...                      # server-side only
CONTRACT_ADDRESS=0xYourErc721Address
RECIPIENT=0xRecipientOrLeaveEmpty         # optional; defaults to minter

# Pinata
PINATA_JWT=eyJhbGciOi...                  # JWT from Pinata dashboard
PINATA_GATEWAY=your-subdomain.mypinata.cloud

# Single mint
IMAGE_PATH=./art/image.png
NAME=My Chiliz NFT
DESCRIPTION=Minted on Chiliz with viem

# Batch mint
IMAGES_DIR=./art
NAME_PREFIX=My Chiliz NFT
BATCH_DESCRIPTION=Batch minted on Chiliz with viem

Agora, vamos mergulhar no código. Use como inspiração, não use como está!

Mintando um único NFT

import 'dotenv/config';
import fs from 'fs';
import path from 'path';

import { createWalletClient, createPublicClient, http, parseEventLogs } from 'viem';
import { privateKeyToAccount } from 'viem/accounts';
import type { Address } from 'viem';
import { chiliz, spicy } from 'viem/chains';
import { PinataSDK } from 'pinata';

// Minimal ABI: safeMint(to, uri) + tokenURI + Transfer
const abi = [
  { type: 'function', name: 'safeMint', stateMutability: 'nonpayable',
    inputs: [{ name: 'to', type: 'address' }, { name: 'uri', type: 'string' }], outputs: [] },
  { type: 'function', name: 'tokenURI', stateMutability: 'view',
    inputs: [{ name: 'tokenId', type: 'uint256' }], outputs: [{ type: 'string' }] },
  { type: 'event', name: 'Transfer',
    inputs: [
      { name: 'from', type: 'address', indexed: true },
      { name: 'to', type: 'address', indexed: true },
      { name: 'tokenId', type: 'uint256', indexed: true },
    ]},
] as const;

function guessMime(p: string) {
  const ext = path.extname(p).toLowerCase();
  if (ext === '.png') return 'image/png';
  if (ext === '.jpg' || ext === '.jpeg') return 'image/jpeg';
  if (ext === '.webp') return 'image/webp';
  if (ext === '.gif') return 'image/gif';
  if (ext === '.mp4') return 'video/mp4';
  if (ext === '.webm') return 'video/webm';
  return 'application/octet-stream';
}

async function main() {
  // Choose your network: use `spicy` for Spicy Testnet, switch to `chiliz` for Chiliz Chain Mainnet.
  const chain = spicy; // Change to `chiliz` for Mainnet

  const account = privateKeyToAccount(process.env.PRIVATE_KEY as `0x${string}`);
  const walletClient = createWalletClient({ account, chain, transport: http() });
  const publicClient = createPublicClient({ chain, transport: http() });

  const address = process.env.CONTRACT_ADDRESS as Address;
  const recipient = (process.env.RECIPIENT as Address) || account.address;

  // IPFS upload (Pinata)
  const pinata = new PinataSDK({
    pinataJwt: process.env.PINATA_JWT!,
    pinataGateway: process.env.PINATA_GATEWAY!,
  });

  const filePath = process.env.IMAGE_PATH!;
  const fileBlob = new Blob([fs.readFileSync(filePath)], { type: guessMime(filePath) });
  const fileObj = new File([fileBlob], path.basename(filePath), { type: guessMime(filePath) });

  const up = await pinata.upload.public.file(fileObj);
  const imageUri = `ipfs://${up.cid}`;

  const meta = await pinata.upload.public.json({
    name: process.env.NAME!,
    description: process.env.DESCRIPTION!,
    image: imageUri,
  });
  const metadataUri = `ipfs://${meta.cid}`;

  // Mint on-chain via viem
  const txHash = await walletClient.writeContract({
    address,
    abi,
    functionName: 'safeMint',
    args: [recipient, metadataUri],
  });

  const receipt = await publicClient.waitForTransactionReceipt({ hash: txHash });

  const ZERO = '0x0000000000000000000000000000000000000000';
  const logs = parseEventLogs({ abi, logs: receipt.logs, eventName: 'Transfer' });
  const mintLog = logs.find(l => (l.args as any).from?.toLowerCase?.() === ZERO);
  const tokenId = mintLog ? (mintLog.args as any).tokenId : undefined;

  console.log('tx:', txHash, '| tokenId:', tokenId ?? '(not parsed)', '| tokenURI:', metadataUri);
}

main().catch(err => (console.error(err), process.exit(1)));

Mintando uma coleção de NFTs

import 'dotenv/config';
import fs from 'fs';
import path from 'path';
// import { Blob } from 'buffer'; // Node 18: uncomment the next line to get Blob.

import { createWalletClient, createPublicClient, http, parseEventLogs } from 'viem';
import { privateKeyToAccount } from 'viem/accounts';
import type { Address } from 'viem';
import { chiliz, spicy } from 'viem/chains';
import { PinataSDK } from 'pinata';

// Minimal ABI: safeMint(to, uri) + tokenURI + Transfer
const abi = [
  { type: 'function', name: 'safeMint', stateMutability: 'nonpayable',
    inputs: [{ name: 'to', type: 'address' }, { name: 'uri', type: 'string' }], outputs: [] },
  { type: 'function', name: 'tokenURI', stateMutability: 'view',
    inputs: [{ name: 'tokenId', type: 'uint256' }], outputs: [{ type: 'string' }] },
  { type: 'event', name: 'Transfer',
    inputs: [
      { name: 'from', type: 'address', indexed: true },
      { name: 'to', type: 'address', indexed: true },
      { name: 'tokenId', type: 'uint256', indexed: true },
    ]},
] as const;

function guessMime(p: string) {
  const ext = path.extname(p).toLowerCase();
  if (ext === '.png') return 'image/png';
  if (ext === '.jpg' || ext === '.jpeg') return 'image/jpeg';
  if (ext === '.webp') return 'image/webp';
  if (ext === '.gif') return 'image/gif';
  if (ext === '.mp4') return 'video/mp4';
  if (ext === '.webm') return 'video/webm';
  return 'application/octet-stream';
}

async function main() {
  // Choose your network: use `spicy` for Spicy Testnet, switch to `chiliz` for Mainnet.
  const chain = spicy; // Change to `chiliz` for Mainnet

  const account = privateKeyToAccount(process.env.PRIVATE_KEY as `0x${string}`);
  const walletClient = createWalletClient({ account, chain, transport: http() });
  const publicClient = createPublicClient({ chain, transport: http() });

  const address = process.env.CONTRACT_ADDRESS as Address;
  const recipient = (process.env.RECIPIENT as Address) || account.address;

  // IPFS upload (Pinata)
  const pinata = new PinataSDK({
    pinataJwt: process.env.PINATA_JWT!,
    pinataGateway: process.env.PINATA_GATEWAY!, // optional; not needed for ipfs:// URIs
  });

  const filePath = process.env.IMAGE_PATH!;
  const fileBlob = new Blob([fs.readFileSync(filePath)], { type: guessMime(filePath) });

  // Pass a Blob directly
  const up = await pinata.upload.public.file(fileBlob);
  const imageUri = `ipfs://${up.cid}`;

  const meta = await pinata.upload.public.json({
    name: process.env.NAME!,
    description: process.env.DESCRIPTION!,
    image: imageUri,
  });
  const metadataUri = `ipfs://${meta.cid}`;

  // Mint on-chain via viem
  const txHash = await walletClient.writeContract({
    address,
    abi,
    functionName: 'safeMint',
    args: [recipient, metadataUri],
  });

  const receipt = await publicClient.waitForTransactionReceipt({ hash: txHash });

  const ZERO = '0x0000000000000000000000000000000000000000';
  const logs = parseEventLogs({ abi, logs: receipt.logs, eventName: 'Transfer' });
  const mintLog = logs.find(l => (l.args as any).from?.toLowerCase?.() === ZERO);
  const tokenId = mintLog ? (mintLog.args as any).tokenId : undefined;

  console.log('tx:', txHash, '| tokenId:', tokenId ?? '(not parsed)', '| tokenURI:', metadataUri);
}

main().catch(err => (console.error(err), process.exit(1)));