Skip to main content

Error Handling & Best Practices

Essential error handling patterns and best practices for Oko SDKs.

Common Error Types​

User Rejection​

try {
  await provider.request({
    method: "eth_sendTransaction",
    params: [transaction],
  });
} catch (error) {
  if (error.code === ProviderRpcErrorCode.UserRejectedRequest) {
    console.log("User rejected transaction");
  }
}

Insufficient Funds​

try {
  await provider.request({
    method: "eth_sendTransaction",
    params: [transaction],
  });
} catch (error) {
  if (error.message.match(/insufficient|funds|balance/i)) {
    console.log("Insufficient balance");
  }
}

Gas Estimation​

try {
  const gasEstimate = await provider.request({
    method: "eth_estimateGas",
    params: [transaction],
  });
  const gasEstimate = await publicClient.estimateGas(transaction);
  const gasLimit = (BigInt(gasEstimate) * BigInt(120)) / BigInt(100); // 20% margin
} catch (error) {
  // Fallback to default gas
  const gasLimit = BigInt(21000);
}

Transaction Monitoring​

export async function monitorTransaction(hash, publicClient, timeout = 60000) {
  const startTime = Date.now();

  while (Date.now() - startTime < timeout) {
    try {
      const receipt = await provider.request({
        method: "eth_getTransactionReceipt",
        params: [hash],
      });

      if (receipt) {
        return {
          status: receipt.status === "0x1" ? "success" : "failed",
          receipt,
        };
      }
    } catch (error) {
      // Transaction not yet mined
    }

    await new Promise((resolve) => setTimeout(resolve, 2000));
  }

  return { status: "timeout" };
}

Best Practices​

Always Handle Errors​

// Good
try {
  const result = await walletClient.sendTransaction(transaction);
  console.log("Transaction sent:", result);
} catch (error) {
  console.error("Transaction failed:", error);
  // Show user-friendly error message
}

// Bad
const result = await walletClient.sendTransaction(transaction); // Unhandled promise

Provide User Feedback​

const [isLoading, setIsLoading] = useState(false);
const [error, setError] = useState(null);

const handleTransaction = async () => {
  setIsLoading(true);
  setError(null);

  try {
    const result = await walletClient.sendTransaction(transaction);
    // Show success message
  } catch (err) {
    setError(err.message);
    // Show error message
  } finally {
    setIsLoading(false);
  }
};

Log Errors for Debugging​

try {
  await walletClient.sendTransaction(transaction);
} catch (error) {
  console.error("Transaction failed:", {
    error: error.message,
    code: error.code,
    transaction,
    timestamp: new Date().toISOString(),
  });
  throw error;
}

Next Steps​