ERC20 101

Introduction

Welcome! This is an automated workshop that will explain how to deploy and ERC20 token, and customize it to perform specific functions. It is aimed at developpers that have never written code in Solidity, but who understand its syntax.

How to work on this TD

Introduction

The TD has two components:

• An ERC20 token, ticker TD-ERC20-101, that is used to keep track of points
• An evaluator contract, that is able to mint and distribute TD-ERC20-101 points

Your objective is to gather as many TD-ERC20-101 points as possible. Please note :

• The 'transfer' function of TD-ERC20-101 has been disabled to encourage you to finish the TD with only one address
• You can answer the various questions of this workshop with different ERC20 contracts. However, an evaluated address has only one evaluated ERC20 contract at a time. To change the evaluated ERC20 contract associated with your address, call submitExercice() with that specific address.
• In order to receive points, you will have to do execute code in Evaluator.sol such that the function TDERC20.distributeTokens(msg.sender, n); is triggered, and distributes n points.
• This repo contains an interface IExerciceSolution.sol. Your ERC20 contract will have to conform to this interface in order to validate the exercice; that is, your contract needs to implement all the functions described in IExerciceSolution.sol.
• A high level description of what is expected for each exercice is in this readme. A low level description of what is expected can be inferred by reading the code in Evaluator.sol.
• The Evaluator contract sometimes needs to make payments to buy your tokens. Make sure he has enough ETH to do so! If not, you can send ETH directly to the contract.

Getting to work

• Clone the repo on your machine
• Install the required packages npm install truffle, npm install @openzeppelin/contracts@3.4.1 , npm install @truffle/hdwallet-provider
• Renam example-truffle-config.js to truffle-config.js . That is now your truffle config file.
• Configure a seed for deployment of contracts in your truffle config file
• Register for an infura key and set it up in your truffle config file
• Download and launch Ganache
• Test that you are able to connect to the goerli network with truffle console
• Test that you are able to connect to the goerli network with truffle console --network goerli
• To deploy a contract, configure a migration in the migration folder. Look at the way the TD is deploy and try to iterate
• Test your deployment in Ganache truffle migrate
• Deploy on goerli truffle migrate --network goerli --skip-dry-run

Points list

Setting up

• Create a git repository and share it with the teacher
• Install truffle and create an empty truffle project (2 pts). Create an infura API key to be able to deploy to the goerli testnet These points will be attributed manually if you do not manage to have your contract interact with the evaluator, or automatically in the first question.

ERC20 basics

• Call ex1_getTickerAndSupply() in the evaluator contract to receive a random ticker for your ERC20 token, as well as an initial token supply (1 pt). You can read your assigned ticker and supply in Evaluator.sol by calling getters readTicker() and readSupply()
• Create an ERC20 token contract with the proper ticker and supply (2 pt)
• Deploy it to the goerli testnet (1 pts)
• Call submitExercice() in the Evaluator to configure the contract you want evaluated (Previous 5 points are attributed at that step)
• Call ex2_testErc20TickerAndSupply() in the evaluator to receive your points (2 pts)

Distributing and selling tokens

• Create a getToken() function in your contract, deploy it, and call the ex3_testGetToken() function that distributes token to the caller (2 pts).
• Create a buyToken() function in your contract, deploy it, and call the ex4_testBuyToken() function that lets the caller send an arbitrary amount of ETH, and distributes a proportionate amount of token (2 pts).

Creating an ICO allow list

• Create a customer allow listing function. Only allow listed users should be able to call getToken()
• Call ex5_testDenyListing() in the evaluator to show he can't buy tokens using buyTokens() (1 pt)
• Allow the evaluator to buy tokens
• Call ex6_testAllowListing()in the evaluator to show he can now buy tokens buyTokens() (2 pt)

Creating multi tier allow list

• Create a customer multi tier listing function. Only allow listed users should be able to call buyToken(); and customers should receive a different amount of token based on their level
• Call ex7_testDenyListing() in the evaluator to show he can't buy tokens using buyTokens() (1 pt)
• Add the evaluator in the first tier. He should now be able to buy N tokens for Y amount of ETH
• Call ex8_testTier1Listing() in the evaluator to show he can now buy tokens(2 pt)
• Add the evaluator in the second tier. He should now be able to buy 2N tokens for Y amount of ETH
• Call ex9_testTier2Listing() in the evaluator to show he can now buy more tokens(2 pt)

All in one

• Finish all the workshop in a single transaction! Write a contract that implements a function called completeWorkshop() when called. Call ex10_allInOne() from this contract. All points are credited to the validating contract (2pt)

Extra points

Extra points if you find bugs / corrections this TD can benefit from, and submit a PR to make it better. Ideas:

• Adding a way to check the code of a specific contract was only used once (no copying)

TD addresses

• Points contracts 0x09f14a40Fd672B5B056FF8b5c343498452CAC4b2
• Evaluator 0x7C5629d850eCD1E640b1572bC0d4ac5210b38FA5