sahilrajput03

Upgradable contracts - UUPS (better than Transparent Proxy)

Source: Official Openzeppelin youtube channel

All resources related to Upgradability from Openzeppelin: Click here

Depending on where we put the upgradeTo() function we decide b/w two types of upgradable smart contracts.

sahilrajput03

sahilrajput03

Commentary on ERC721

Source: ethereum.org

Implementation on Openzeppelin:

• Openzeppelin Implementation: Click here, Cleaned by me

Every ERC-721 compliant contract must implement the ERC721 and ERC165 interfaces:

• Methods:

sahilrajput03

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC721/ERC721.sol)

pragma solidity ^0.8.0;

import './IERC721.sol';
import './IERC721Receiver.sol';
import './extensions/IERC721Metadata.sol';
import '../../utils/Address.sol';
import '../../utils/Context.sol';

sahilrajput03

Commentary on ERC20

Source: ethereum.org

• Methods:

  - name(): OPTIONAL, Returns the name of the token - e.g. "MyToken". ALSO: `function name() public view returns (string)`
  - symbol(): OPTIONAL, Returns the symbol of the token. E.g. “HIX”. ALSO: `function symbol() public view returns (string)`
  - decimals(): OPTIONAL, Returns the number of decimals the token uses - e.g. 8, means to divide the token amount by 100000000 to get its user representation. ALSO: `function decimals() public view returns (uint8)`
  - totalSupply(): Returns the total token supply. ALSO: `function totalSupply() public view returns (uint256)`

sahilrajput03

// source: http://stackoverflow.com/a/11058858
function ab2str(buf) {
  return String.fromCharCode.apply(null, new Uint16Array(buf));
}

sahilrajput03

Commentary on ERC1155 - Multi Token Standard

Source: ethereum.org

• Implementation on Openzeppelin: Click here
• Implementation with Video Tutorial: @youtube Click here

Smart contracts implementing the ERC-1155 standard MUST implement all of the functions in the ERC1155 interface.

Smart contracts implementing the ERC-1155 standard MUST implement the ERC-165 supportsInterface function and MUST return the constant value true if 0xd9b67a26 is passed through the interfaceID argument.

sahilrajput03

Quick Links:

• ERC 1155 @ Openzeppelin Docs: https://docs.openzeppelin.com/contracts/3.x/ERC1155
• Morali.io - A faster way to develop dapps
• tldr; This youtube guy is from Morali.io
• ERC721 vs. ERC1155 by EatTheBlocks: Click here

Amazing explanation of ERC721

sahilrajput03

sahilrajput03

Get a Free SSL Certificate With Let’s Encrypt

Let’s Encrypt is a free, automated, and open Certificate Authority.

1. Install tools for using the Let's Encrypt certificates using Certbot

  sudo apt-get update \
  sudo apt-get install software-properties-common