Arbitrum - Leading Ethereum L2 Scaling Solution

// Watch for transaction confirmation
async function waitForTransaction(txHash) {
  const receipt = await provider.waitForTransaction(txHash, 1);

  // L2 specific: Check L1 data availability
  if (receipt.l1Fee) {
    console.log('L1 data cost:', receipt.l1Fee);
  }

  return receipt;
}

// Estimate L2 execution gas
const l2Gas = await provider.estimateGas(tx);

// Get current L1 data fee (Arbitrum specific)
const l1DataFee = await provider.send('eth_estimateL1Fee', [tx]);

// Total cost = L2 execution + L1 data posting
const totalCost = l2Gas + BigInt(l1DataFee);

// Query events with automatic retry and pagination
async function getEvents(contract, eventName, fromBlock = 0) {
  const filter = contract.filters[eventName]();
  const events = [];
  const batchSize = 2000; // Arbitrum recommended batch size

  for (let i = fromBlock; i <= currentBlock; i += batchSize) {
    const batch = await contract.queryFilter(
      filter,
      i,
      Math.min(i + batchSize - 1, currentBlock)
    );
    events.push(...batch);
  }

  return events;
}

const batch = [
  { method: 'eth_blockNumber', params: [] },
  { method: 'eth_gasPrice', params: [] },
  { method: 'eth_getBalance', params: [address, 'latest'] }
];

const results = await provider.send(batch);

// Singleton pattern for provider
class ArbitrumProvider {
  static instance = null;

  static getInstance() {
    if (!this.instance) {
      this.instance = new JsonRpcProvider(
        'https://api-arbitrum-mainnet-archive.n.dwellir.com/YOUR_API_KEY'
      );
    }
    return this.instance;
  }
}

const cache = new Map();

async function getCachedBlockData(blockNumber) {
  const key = `block_${blockNumber}`;

  if (!cache.has(key)) {
    const block = await provider.getBlock(blockNumber);
    cache.set(key, block);
  }

  return cache.get(key);
}

// Always account for L1 fees in balance checks
const balance = await provider.getBalance(address);
const l1Fee = await provider.send('eth_estimateL1Fee', [tx]);
const l2Gas = await provider.estimateGas(tx);
const totalRequired = l2Gas + BigInt(l1Fee) + tx.value;

if (balance < totalRequired) {
  throw new Error(`Need ${totalRequired - balance} more ETH`);
}

// Get current fee data
const feeData = await provider.getFeeData();

const tx = {
  to: recipient,
  value: amount,
  maxFeePerGas: feeData.maxFeePerGas,
  maxPriorityFeePerGas: feeData.maxPriorityFeePerGas,
  gasLimit: 21000n
};

async function callWithRetry(fn, maxRetries = 3) {
  for (let i = 0; i < maxRetries; i++) {
    try {
      return await fn();
    } catch (error) {
      if (error.code === 429 && i < maxRetries - 1) {
        await new Promise(r => setTimeout(r, 2 ** i * 1000));
      } else {
        throw error;
      }
    }
  }
}

// Before (Ethereum)
const provider = new JsonRpcProvider('https://eth-rpc.example.com');

// After (Arbitrum)
const provider = new JsonRpcProvider(
  'https://api-arbitrum-mainnet-archive.n.dwellir.com/YOUR_API_KEY'
);

// Smart contracts work identically
// Same tooling and libraries
// Note: Different chain ID (42161)
// Note: Separate block numbers
// Note: L1 data fees apply