Rate limits

async function rpcWithRetry(provider, method, params, maxRetries = 5) {
  for (let attempt = 0; attempt < maxRetries; attempt++) {
    try {
      return await provider.send(method, params);
    } catch (err) {
      if (err.status === 429 || err.code === "SERVER_ERROR") {
        const delay = Math.min(1000 * 2 ** attempt, 30_000);
        console.warn(`Rate limited, retrying in ${delay}ms...`);
        await new Promise(r => setTimeout(r, delay));
      } else {
        throw err;
      }
    }
  }
  throw new Error("Max retries exceeded");
}

const wsProvider = new ethers.WebSocketProvider("wss://rpc1.autheo.com:8546");
wsProvider.on("block", (blockNumber) => {
  console.log("New block:", blockNumber);
});

// Instead of one huge query from block 0 to latest:
const logs = await contract.queryFilter("Transfer", 0, "latest"); // ❌ may hit limits

// Use paginated chunks:
for (let from = 0; from < currentBlock; from += 5000) {
  const to = Math.min(from + 4999, currentBlock);
  const chunk = await contract.queryFilter("Transfer", from, to); // ✅
}

const endpoints = [
  "https://rpc1.autheo.com",
  "https://testnet-rpc2.autheo.com"
];

let index = 0;
function getProvider() {
  const url = endpoints[index % endpoints.length];
  index++;
  return new ethers.JsonRpcProvider(url);
}