Contract verification on Etherscan in Blockchain / Solidity - Mini Project: Build & Apply

Contract verification on Etherscan

📖 Scenario: You have just deployed a smart contract on the Ethereum blockchain. To make your contract's source code public and allow others to verify it, you need to verify your contract on Etherscan.This project will guide you through the steps to prepare and submit your contract for verification on Etherscan.

🎯 Goal: Learn how to prepare your smart contract source code and metadata, and submit it to Etherscan for verification.

📋 What You'll Learn

Have a deployed smart contract address

Have the exact source code of the deployed contract

Know the compiler version used for deployment

Understand how to use Etherscan's contract verification interface

💡 Why This Matters

🌍 Real World

Verifying your smart contract on Etherscan makes your code public and trustworthy. It helps users and developers see exactly what your contract does.

💼 Career

Blockchain developers often need to verify contracts to ensure transparency and security. This skill is essential for roles involving smart contract deployment and auditing.

1

Prepare the contract source code

Create a string variable called source_code that contains the exact Solidity source code of your deployed contract. Use triple quotes to include multiple lines.

Blockchain / Solidity

# Your code here

Need a hint?

Use triple quotes ''' to write the full Solidity code as a string.

2

Specify the compiler version

Create a string variable called compiler_version and set it to the exact Solidity compiler version used to deploy the contract, for example, "v0.8.0+commit.c7dfd78e".

Blockchain / Solidity

source_code = '''
pragma solidity ^0.8.0;

contract SimpleStorage {
    uint256 public storedData;

    function set(uint256 x) public {
        storedData = x;
    }

    function get() public view returns (uint256) {
        return storedData;
    }
}
'''
# Your code here

Need a hint?

Check your deployment logs or compiler settings to find the exact compiler version string.

3

Prepare the verification metadata

Create a dictionary called verification_data with keys "address", "sourceCode", and "compilerVersion". Set "address" to the deployed contract address "0x1234567890abcdef1234567890abcdef12345678", "sourceCode" to the source_code variable, and "compilerVersion" to the compiler_version variable.

Blockchain / Solidity

source_code = '''
pragma solidity ^0.8.0;

contract SimpleStorage {
    uint256 public storedData;

    function set(uint256 x) public {
        storedData = x;
    }

    function get() public view returns (uint256) {
        return storedData;
    }
}
'''

compiler_version = "v0.8.0+commit.c7dfd78e"

# Your code here

Need a hint?

Use a dictionary with the exact keys and values as described.

4

Print the verification data

Write a print statement to display the verification_data dictionary.

Blockchain / Solidity

source_code = '''
pragma solidity ^0.8.0;

contract SimpleStorage {
    uint256 public storedData;

    function set(uint256 x) public {
        storedData = x;
    }

    function get() public view returns (uint256) {
        return storedData;
    }
}
'''

compiler_version = "v0.8.0+commit.c7dfd78e"

verification_data = {
    "address": "0x1234567890abcdef1234567890abcdef12345678",
    "sourceCode": source_code,
    "compilerVersion": compiler_version
}

# Your code here

Need a hint?

Use print(verification_data) to show the dictionary.