Link to video - https://youtu.be/bPOOvyVpI9U
First deploy the logic contract (MyContract). Then deploy the Proxy contract. In the arguments for Proxy contract's constructor, send the calldata and address of MyContract. To compute the calldata, run this in the remix console -
web3.utils.sha3('initialize()').substr(0, 10)
If the initialization function is different for your contract, change the initialize() to your contract's function name.
| <!DOCTYPE html> | |
| <html> | |
| <head> | |
| <meta charset="utf-8"> | |
| <meta name="viewport" content="width=device-width, initial-scale=1"> | |
| <title>Connect to Proxy</title> | |
| <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.1.3/dist/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-1BmE4kWBq78iYhFldvKuhfTAU6auU8tT94WrHftjDbrCEXSU1oBoqyl2QvZ6jIW3" crossorigin="anonymous"> | |
| <script src="https://cdn.jsdelivr.net/npm/web3@latest/dist/web3.min.js"></script> | |
| </head> | |
| <body> | |
| <div class="container mt-5"> | |
| <div class="row"> | |
| <div class="col-6 offset-3"> | |
| <div id="beforeconnect"> | |
| <button class="btn btn-primary mt-3" id="connect">connect</button> | |
| </div> | |
| <div id="afterconnect"> | |
| <div> | |
| <button class="btn btn-primary mt-3" id="increment">increment</button> | |
| </div> | |
| <div> | |
| <button class="btn btn-primary mt-3" id="current">Get Current Value</button> | |
| <h3>Current Value: <span id="currentVal"></span></h3> | |
| </div> | |
| </div> | |
| </div> | |
| </div> | |
| </div> | |
| <script type="text/javascript"> | |
| document.getElementById('afterconnect').hidden = true | |
| var account = null; | |
| var contract = null; | |
| const connect = async () => { | |
| if (window.ethereum) { | |
| await window.ethereum.send('eth_requestAccounts'); | |
| window.web3 = new Web3(window.ethereum); | |
| var accounts = await web3.eth.getAccounts(); | |
| account = accounts[0]; | |
| contract = new web3.eth.Contract(ABI, ADDRESS); | |
| document.getElementById('beforeconnect').hidden = true | |
| document.getElementById('afterconnect').hidden = false | |
| document.getElementById('current').onclick = current; | |
| document.getElementById('increment').onclick = increment; | |
| await current() | |
| } else { | |
| alert('Metamask not detected') | |
| } | |
| } | |
| const increment = async () => { | |
| if (contract) { | |
| await contract.methods.increment().send({ from: account }); | |
| await current() | |
| } | |
| } | |
| const current = async () => { | |
| if (contract) { | |
| var count = await contract.methods.count().call() | |
| document.getElementById('currentVal').innerHTML = count; | |
| } | |
| } | |
| document.getElementById('connect').onclick = connect; | |
| var ADDRESS = '0xf54B9DccD560E20b89CfF60B92ce339c9E3d866D' | |
| var ABI = [{"inputs":[],"name":"count","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"decrement","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"increment","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"initalized","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"initialize","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"owner","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"proxiableUUID","outputs":[{"internalType":"bytes32","name":"","type":"bytes32"}],"stateMutability":"pure","type":"function"},{"inputs":[{"internalType":"address","name":"newCode","type":"address"}],"name":"updateCode","outputs":[],"stateMutability":"nonpayable","type":"function"}] | |
| </script> | |
| <style type="text/css"> | |
| </style> | |
| </body> | |
| </html> |
| //SPDX-License-Identifier: MIT | |
| pragma solidity ^0.8.1; | |
| import "./Proxiable.sol"; | |
| contract MyContract is Proxiable { | |
| address public owner; | |
| uint public count; | |
| bool public initalized = false; | |
| function initialize() public { | |
| require(owner == address(0), "Already initalized"); | |
| require(!initalized, "Already initalized"); | |
| owner = msg.sender; | |
| initalized = true; | |
| } | |
| function increment() public { | |
| count++; | |
| } | |
| function updateCode(address newCode) onlyOwner public { | |
| updateCodeAddress(newCode); | |
| } | |
| modifier onlyOwner() { | |
| require(msg.sender == owner, "Only owner is allowed to perform this action"); | |
| _; | |
| } | |
| } |
| //SPDX-License-Identifier: MIT | |
| pragma solidity ^0.8.1; | |
| import "./Proxiable.sol"; | |
| contract MyContract2 is Proxiable { | |
| address public owner; | |
| uint public count; | |
| bool public initalized = false; | |
| function initialize() public { | |
| require(owner == address(0), "Already initalized"); | |
| require(!initalized, "Already initalized"); | |
| owner = msg.sender; | |
| initalized = true; | |
| } | |
| function increment() public { | |
| count++; | |
| } | |
| function decrement() public { | |
| count--; | |
| } | |
| function updateCode(address newCode) onlyOwner public { | |
| updateCodeAddress(newCode); | |
| } | |
| modifier onlyOwner() { | |
| require(msg.sender == owner, "Only owner is allowed to perform this action"); | |
| _; | |
| } | |
| } |
| //SPDX-License-Identifier: MIT | |
| pragma solidity ^0.8.1; | |
| contract Proxiable { | |
| // Code position in storage is keccak256("PROXIABLE") = "0xc5f16f0fcc639fa48a6947836d9850f504798523bf8c9a3a87d5876cf622bcf7" | |
| function updateCodeAddress(address newAddress) internal { | |
| require( | |
| bytes32(0xc5f16f0fcc639fa48a6947836d9850f504798523bf8c9a3a87d5876cf622bcf7) == Proxiable(newAddress).proxiableUUID(), | |
| "Not compatible" | |
| ); | |
| assembly { // solium-disable-line | |
| sstore(0xc5f16f0fcc639fa48a6947836d9850f504798523bf8c9a3a87d5876cf622bcf7, newAddress) | |
| } | |
| } | |
| function proxiableUUID() public pure returns (bytes32) { | |
| return 0xc5f16f0fcc639fa48a6947836d9850f504798523bf8c9a3a87d5876cf622bcf7; | |
| } | |
| } |
| //SPDX-License-Identifier: MIT | |
| pragma solidity ^0.8.1; | |
| contract Proxy { | |
| // Code position in storage is keccak256("PROXIABLE") = "0xc5f16f0fcc639fa48a6947836d9850f504798523bf8c9a3a87d5876cf622bcf7" | |
| constructor(bytes memory constructData, address contractLogic) { | |
| // save the code address | |
| assembly { // solium-disable-line | |
| sstore(0xc5f16f0fcc639fa48a6947836d9850f504798523bf8c9a3a87d5876cf622bcf7, contractLogic) | |
| } | |
| (bool success, bytes memory result ) = contractLogic.delegatecall(constructData); // solium-disable-line | |
| require(success, "Construction failed"); | |
| } | |
| fallback() external payable { | |
| assembly { // solium-disable-line | |
| let contractLogic := sload(0xc5f16f0fcc639fa48a6947836d9850f504798523bf8c9a3a87d5876cf622bcf7) | |
| calldatacopy(0x0, 0x0, calldatasize()) | |
| let success := delegatecall(sub(gas(), 10000), contractLogic, 0x0, calldatasize(), 0, 0) | |
| let retSz := returndatasize() | |
| returndatacopy(0, 0, retSz) | |
| switch success | |
| case 0 { | |
| revert(0, retSz) | |
| } | |
| default { | |
| return(0, retSz) | |
| } | |
| } | |
| } | |
| } |