SaveContract

A CLI tool to download verified smart contract source code from Etherscan and other Etherscan-powered block explorers using the official V2 API.

Features

• Multi-Chain Support: Download contracts from Ethereum, Base, Arbitrum, Polygon, and any other chain supported by the Etherscan V2 API.
• Correct File Structure: Automatically parses the Standard JSON Input format to recreate the correct directory structure and file paths.
• Easy to Use: Simple and intuitive command-line interface.
• Environment Variable Support: Configure your API key once in a .env file.

Installation

You can run savecontract directly using npx without installation.

npx savecontract --address <contract_address> [options]

Or, you can install it globally for easier access:

npm install -g savecontract

Usage

Basic Command

savecontract --address <contract_address> --chainid <chain> --apikey <your_api_key> --output <directory>

Arguments and Options

| Long Flag | Short Flag | Description | Default | | ----------- | ------------ | ----------------------------------------------------------- | ------------------ | | --address | -a | (Required) The contract address to download. | - | | --chainid | -c, -cid | Chain ID or name (e.g., "1", "ethereum", "8453", "base"). | "1" (Ethereum) | | --output | -o | The output directory for the contract files. | ./smartcontracts | | --apikey | -k | Your Etherscan API key. Overrides the environment variable. | - | | --module | -m | API module to use. | "contract" | | --action | | API action to use. | "getsourcecode" | | --help | -h | Show help. | - | | --version | -v | Show version number. | - |

API Key Setup

An Etherscan API key (from the free tier) is required. You can provide it in two ways:

1. Via Command Line (highest priority):

   savecontract -a 0x... -k YOUR_API_KEY

2. Via .env file (recommended): Create a .env file in the directory where you are running the command and add your key:

   ETHERSCAN_API_KEY=YOUR_API_KEY

Examples

1. Download a contract from Base mainnet:

npx savecontract -a 0x03059433BCdB6144624cC2443159D9445C32b7a8 -c base -o ./base_contracts

(This assumes your API key is in a .env file)

2. Download a contract from Ethereum mainnet (default chain):

npx savecontract -a 0xBB9bc244D798123fDe783fCc1C72d3Bb8C189413

3. Specify API key directly for a contract on Polygon:

npx savecontract --address 0x... --chainid polygon --apikey YOUR_API_KEY

Supported Chains

This tool supports any chain available on the Etherscan V2 API. Use either the chain ID or one of the convenient names below:

| Chain Name | Chain ID | | ------------------------- | ----------- | | Ethereum Mainnet | 1 | | Sepolia Testnet | 11155111 | | Holesky Testnet | 17000 | | Hoodi Testnet | 560048 | | Abstract Mainnet | 2741 | | Abstract Sepolia Testnet | 11124 | | ApeChain Curtis Testnet | 33111 | | ApeChain Mainnet | 33139 | | Arbitrum Nova Mainnet | 42170 | | Arbitrum One Mainnet | 42161 | | Arbitrum Sepolia Testnet | 421614 | | Avalanche C-Chain | 43114 | | Avalanche Fuji Testnet | 43113 | | Base Mainnet | 8453 | | Base Sepolia Testnet | 84532 | | Berachain Mainnet | 80094 | | Berachain Bepolia Testnet | 80069 | | BitTorrent Chain Mainnet | 199 | | BitTorrent Chain Testnet | 1028 | | Blast Mainnet | 81457 | | Blast Sepolia Testnet | 168587773 | | BNB Smart Chain Mainnet | 56 | | BNB Smart Chain Testnet | 97 | | Celo Alfajores Testnet | 44787 | | Celo Mainnet | 42220 | | Cronos Mainnet | 25 | | Fraxtal Mainnet | 252 | | Fraxtal Testnet | 2522 | | Gnosis | 100 | | HyperEVM | 999 | | Linea Mainnet | 59144 | | Linea Sepolia Testnet | 59141 | | Mantle Mainnet | 5000 | | Mantle Sepolia Testnet | 5003 | | Memecore Mainnet | 4352 | | Memecore Testnet | 43521 | | Moonbase Alpha Testnet | 1287 | | Monad Testnet | 10143 | | Moonbeam Mainnet | 1284 | | Moonriver Mainnet | 1285 | | OP Mainnet | 10 | | OP Sepolia Testnet | 11155420 | | Polygon Amoy Testnet | 80002 | | Polygon Mainnet | 137 | | Katana Mainnet | 747474 | | Scroll Mainnet | 534352 | | Scroll Sepolia Testnet | 534351 | | Sonic Blaze Testnet | 57054 | | Sonic Mainnet | 146 | | Sophon Mainnet | 50104 | | Sophon Sepolia Testnet | 531050104 | | Swellchain Mainnet | 1923 | | Swellchain Testnet | 1924 | | Taiko Hekla L2 Testnet | 167009 | | Taiko Mainnet | 167000 | | Unichain Mainnet | 130 | | Unichain Sepolia Testnet | 1301 | | WEMIX3.0 Mainnet | 1111 | | WEMIX3.0 Testnet | 1112 | | World Mainnet | 480 | | World Sepolia Testnet | 4801 | | Xai Mainnet | 660279 | | Xai Sepolia Testnet | 37714555429 | | XDC Apothem Testnet | 51 | | XDC Mainnet | 50 | | zkSync Mainnet | 324 | | zkSync Sepolia Testnet | 300 | | opBNB Mainnet | 204 | | opBNB Testnet | 5611 |

License

MIT