eth_getCode

Fetches the compiled bytecode of smart contracts deployed on IoTeX One network. This method is crucial for contract verification, security auditing, and analyzing DeFi protocols on IoTeX's high-performance Layer 2 solution.

Parameters

Parameter	Type	Required	Description
address	string	Yes	The 20-byte contract address (0x-prefixed hex string)
blockNumber/blockTag	string	Yes	Block number in hex (e.g., "0x1b4") or block tag: "latest", "earliest", "pending", "safe", "finalized"

Block Tags

• latest - Most recent block in the canonical chain
• earliest - Genesis block
• pending - Pending state/transactions
• safe - Latest safe head block (IoTeX)
• finalized - Latest finalized block (IoTeX)

Returns

Returns the contract bytecode as a hex-encoded string. Externally Owned Accounts (EOAs) return "0x".

Type	Description
string	Hex-encoded contract bytecode starting with "0x". Returns "0x" for EOA addresses

Code Examples

cURL

# Get bytecode for USDC contract on IoTeX
curl -X POST https://api-iotex-mainnet.n.dwellir.com/YOUR_API_KEY \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_getCode",
    "params": [
      "0xaf88d065e77c8cC2239327C5EDb3A432268e5831",
      "latest"
    ],
    "id": 1
  }'

JavaScript

// Get bytecode for Uniswap V3 Router on IoTeX
const response = await fetch('https://api-iotex-mainnet.n.dwellir.com/YOUR_API_KEY', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({
    jsonrpc: '2.0',
    method: 'eth_getCode',
    params: [
      '0xE592427A0AEce92De3Edee1F18E0157C05861564',
      'latest'
    ],
    id: 1
  })
});

const data = await response.json();
console.log('Uniswap Router bytecode:', data.result);

// Verify contract deployment
if (data.result === '0x') {
  console.log('No contract found at this address');
} else {
  console.log('Contract verified on IoTeX');
  console.log(`Bytecode size: ${(data.result.length - 2) / 2} bytes`);
}

Python

import requests
import json

# Get bytecode for GMX token contract on IoTeX
url = "https://api-iotex-mainnet.n.dwellir.com/YOUR_API_KEY"
payload = {
    "jsonrpc": "2.0",
    "method": "eth_getCode",
    "params": [
        "0xfc5A1A6EB076a2C7aD06eD22C90d7E710E35ad0a",  # GMX token
        "latest"
    ],
    "id": 1
}

response = requests.post(url, json=payload)
result = response.json()

if result['result'] == '0x':
    print("Address is an EOA")
else:
    bytecode = result['result']
    print(f"GMX Contract bytecode: {bytecode[:100]}...")
    print(f"Contract size: {(len(bytecode) - 2) // 2} bytes")
    
    # Check for proxy patterns
    if "363d3d373d3d3d363d73" in bytecode:
        print("Detected: Minimal proxy pattern")
    elif "608060405234801561001057600080fd5b50" in bytecode:
        print("Detected: Standard Solidity contract")

Response Example

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "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}

Important Notes

EOA vs Contract Addresses

• Contract addresses: Return the deployed smart contract bytecode
• EOA addresses: Return "0x" as they contain no executable code
• Essential for distinguishing between user accounts and smart contracts

Use Cases

• DeFi protocol analysis: Examine deployed protocol logic on IoTeX
• Contract verification: Validate source code against deployed bytecode
• Security auditing: Analyze contract patterns and potential vulnerabilities
• Proxy contract detection: Identify upgradeable proxy implementations

IoTeX-Specific Considerations

• IoTeX One uses Optimistic Rollup technology for scalability
• Bytecode format is fully compatible with Ethereum
• Lower gas costs enable complex smart contract interactions
• Full EVM compatibility ensures seamless contract deployment

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