Big Update: New Sepolia Faucet Located Here. \Kovan, Ropsten, and Rinkeby have been deprecated. Goerli Still works but we highly recommend Sepolia as its proof of stake based.
You'll need to verify via Twitter to get ETH & LINK. You can find Backup Faucets here.
Additionally, lesson 7 uses Chainlink VRF v1 instead of v2, you can find the docs for Chainlink VRFv1 here.
Welcome to the repository for the Ultimate Solidity, Blockchain, and Smart Contract - Beginner to Expert Full Course | Python Edition FreeCodeCamp course!
Table of Contents
- Table of Contents
- Resources For This Course
- Lesson 0: Welcome To Blockchain
- Lesson 1: Welcome to Remix! Simple Storage
- Lesson 2: Storage Factory
- Lesson 3: Fund Me
- Lesson 4: Web3.py Simple Storage
- Lesson 5: Brownie Simple Storage
- Lesson 6: Brownie Fund Me
- Lesson 7: SmartContract Lottery
- Lesson 8: Chainlink Mix
- Lesson 9: ERC20s, EIPs, and Token Standards
- Lesson 10: Defi & Aave
- Lesson 11: NFTs
- Lesson 12: Upgrades
- Bonus Lesson 13: Full Stack Defi
- Closing and Summary
Resources For This Course
Questions
- Github Discussions
- Ask questions and chat about the course here!
- Stack Exchange Ethereum
- Great place for asking technical questions about Ethereum
- StackOverflow
- Great place for asking technical questions overall
Windows Support
- Setup your windows environment
- Learn how to install all the tools you will need for this course on a windows machine
Hiccups/Issues from the Video
- Chronological Issues from the Video
- A list of known hiccups/issues you may encounter while implementing the content from the video
Lesson 0: Welcome To Blockchain
What is a Blockchain?
- Bitcoin Whitepaper
- Ethereum Whitepaper
- Hybrid Smart Contracts
- Blockchain Oracles
- What is a blockchain
Making Your First Transaction
-
Rinkeby Faucet (Check the link token contracts page)
- NOTE: You can always find the most up to date faucets at faucets.chain.link.
-
OR, use the Kovan ETH Faucet, just be sure to swap your metamask to kovan!
How Do Blockchains Work?
- Blockchain Demo
- Public / Private Keys
- Layer 2 and Rollups
- Decentralized Blockchain Oracles
- Block Rewards
- Run Your Own Ethereum Node
Consensus
The Future
Miscellaneous
Lesson 1: Welcome to Remix! Simple Storage
š» Code: https://github.com/PatrickAlphaC/simple_storage
Everything in this section can be read about in the Solidity Documentation
Remix
Basic Solidity
- Versioning
- Compiling
- Contract Declaration
- Types & Declaring Variables
uint256,int256,bool,string,address,bytes32
- Default Initializations
- Comments
- Functions
- Deploying a Contract
- Calling a public state-changing Function
- Visibility
- Scope
- View & Pure Functions
- Structs
- Intro to Storage
- Arrays - Dynamic & Fixed sized
- Compiler Errors and Warnings
- Memory
- Mappings
- SPDX License
- Recap
Deploying to a "Live" network
- A testnet or mainnet
- Find a faucet here
- Connecting Metamask
- Interacting with Deployed Contracts
- The EVM
Lesson 2: Storage Factory
š» Code: https://github.com/PatrickAlphaC/storage_factory
Inheritance, Factory Pattern, and Interacting with External Contracts
- Factory Pattern
- Imports
- Deploy a Contract From a Contract
- Interact With a Deployed Contract
- Recap
Lesson 3: Fund Me
š» Code: https://github.com/PatrickAlphaC/fund_me
Payable, msg.sender, msg.value, Units of Measure
- Payable
- Wei/Gwei/Eth Converter
- msg.sender & msg.value
Chainlink Oracles
- Decentralized Oracle Network Chainlink
- Blockchains can't make API calls
- Centralized Nodes are Points of Failure
- data.chain.link
- Getting External Data with Chainlink Oracles
Importing from NPM and Advanced Solidity
- Decimals/Floating Point Numbers in Solidity
- latestRoundData
- Importing from NPM in Remix
- Interfaces
- Introduction to ABIs
- Getting Price Feed Addresses
- getPrice
- Tuples
- Unused Tuple Variables
- Matching Units (WEI/GWEI/ETH)
- getConversionRate
- Matching Units (Continued)
- SafeMath & Integer Overflow
- using keyword
- Libraries
- SafeMath PSA
- Setting a Threshold
- Require
- Revert
- Withdraw Function
- Transfer
- Balance
- this
- Contract Owners
- Constructor
- ==
- Modifiers
- Resetting
- for loop
- Array Length
- Forcing a Transaction
- Recap
Lesson 4: Web3.py Simple Storage
š» Code: https://github.com/PatrickAlphaC/web3_py_simple_storage
Installing VSCode, Python, and Web3
- Developer Bootcamp Setup Instructions (metamask, vscode, python, nodejs..)
- VSCode
- VSCode Crash Course
- Extensions
- Short Cuts:
- Python
- Install Troubleshooting
- Terminal
- Making a directory/Folder
- Opening the folder up with VSCode
- Creating a new file
- Syntax Highlights
- Remember to save!
- Setting linting compile version
- VSCode Solidity Settings
- Formatting & Format on Save
- Solidity Prettier
- Python Black
- pip
Our First Python Script with Web3.py - Deploying a Contract
- Reading our solidity file
- Running a Python Script in the Terminal
- MaxOS Shortcuts
- Windows Shortcuts
- Linux Shortcuts
- Compiling in Python
- py-solc-x
- compile_standard
- Colorized Brackets
- JSON ABI
- Saving Compiled Code
- Formatting JSON
- Deploying in Python
- Get Bytecode
- Get ABI
- Choose Blockchain to Deploy To
- Local Ganache Chain
- Ganache UI
- Ganache Command Line
- Web3.py
- HTTP / RPC Provider
- Private Keys MUST start with "0x"
- Contract Object
- Building a Transaction
- Account Nonce
- Calling "Constructor"
- Transaction Parameters
- Signing the Transaction
- NEVER put your private key directly in your code
- Setting Environment Variables (Windows, Linux, MacOS)
- Exported Environment Variables Only Last the Duration of the Shell/Terminal
- Private Key PSA
- .env file
- .gitignore
- Loading .env File in Python
- Viewing our Transaction / Deployment in Ganache
- Waiting for Block Confirmations
Interacting with Our Contract in Python & Web3.py
- 2 Things you always need
- Contract Address
- Contract ABI
- Getting address from transaction receipt
- Calling a view function with web3.py
- Call vs Transact
- Updating State with Web3.py
- ganache-cli
- Installing Ganache
- Install Nodejs
- Install Yarn
- Working with ganache-cli
- Open a new terminal in the same window
- Deploying to a testnet
- Infura
- Alchemy
- Using Infura RPC URL / HTTP Provider
- Chain Ids
- Wow this seems like a lot of work... Is there a better way?
Lesson 5: Brownie Simple Storage
š» Code: https://github.com/PatrickAlphaC/brownie_simple_storage
Brownie Introduction
Installing Brownie
- Installing Brownie
- Install pipx
- pipx install eth-brownie
- Testing Successful Install
Brownie Simple Storage Project
- A new Brownie project with
brownie init- Project Basic Explanation
- Adding
SimpleStorage.solto thecontractsfolder - Compiling with
brownie compile - Brownie deploy script
def mainis brownie's entry point
- brownie defaults to a
developmentganachechain that it creates - Placing functions outside of the
mainfunction - brownie
accounts- 3 Ways to Add Accounts
accounts[0]: Brownie's "default" ganache accounts- Only works for local ganache
accounts.load("..."): Brownie's encrypted command line (MOST SECURE)- Run
brownie accounts new <name>and enter your private key and a password
- Run
accounts.add(config["wallets"]["from_key"]): Storing Private Keys as an environment variable, and pulling from ourbrownie-config.yaml- You'll need to add
dotenv: .envto yourbrownie-config.yamland have a.envfile
- You'll need to add
- 3 Ways to Add Accounts
- Importing a Contract
- Contract.Deploy
- View Function Call in Brownie
- State-Changing Function Call in Brownie / Contract Interaction
transaction.wait(1)
Testing Basics
test_simple_storage.py- Arrange, Act, Assert
assertbrownie testtest_updating_storage- Pytest / Brownie Test Tips
- Deploy to a Testnet
brownie networks list- Development vs Ethereum
- Development is temporary
- Ethereum networks persist
- RPC URL / HTTP Provider in Brownie
- The network flag
list index out of range
get_account()networks.show_active()- build/deployments
- Accessing previous deployments
- Interacting with contracts deployed in our brownie project
[Brownie console]
brownie console
Lesson 6: Brownie Fund Me
š» Code: https://github.com/PatrickAlphaC/brownie_fund_me
Introduction
- Setup
Dependencies, Deploying, and Networks
- Dependencies
- chainlink-brownie-contracts
- remappings
- Deploy Script (V1)
helpful_scripts.py__init__.py- Deploy to Rinkeby
- Contract Verification (
publish_source)- The Manual Way
- "Flattening"
- The Programmatic Way
- Getting an Etherscan API Key
ETHERSCAN_TOKEN- Interacting with Etherscan
- Deploying to Local Chains
- Introduction to Mocking
- Constructor Parameters
networksin ourbrownie-config.yaml- Copying Mock Contracts from chainlink-mix
- Deploying and using our mock
- Refactoring
- Deploying to a persistent ganache
- brownie attach
- Adding a persistent brownie network
- resetting a network build
Funding and Withdrawing Python Scripts
- Whoops! Let's fix an issue...
- Fund Script
- Withdraw Script
Testing across networks
test_can_fund_and_withdraw- default networks
- pytest
pip install pytest - pytest.skip
- brownie exceptions
mainnet-fork- Custom mainnet fork
- Adding a development brownie network
brownie networks add development mainnet-fork-dev cmd=ganache-cli host=http://127.0.0.1 fork='https://infura.io/v3/$WEB3_INFURA_PROJECT_ID' accounts=10 mnemonic=brownie port=8545
- Alchemy
brownie test --network mainnet-fork- brownie ganache vs local ganache vs mainnet-fork vs testnet...
Git
- Installing Git
- Creating a repository
- First time with git
- Adding our project to github
- Tweet it out!
Compatibility with Ganache UI
test_only_owner_can_withdraw()gives below error if the selected network is Ganache UI::
E ValueError: Execution reverted during call: 'VM Exception while processing transaction: revert'. This transaction will likely revert. If you wish to broadcast, include `allow_revert:True` as a transaction parameter.Lesson 7: SmartContract Lottery
š» Code: https://github.com/PatrickAlphaC/smartcontract-lottery
Introduction
- Add a
README.md - Defining the project
- Is it decentralized?
Lottery.sol
- basic setup
- Main Functions
- address payable[]
- getEntranceFee & Setup
- Chainlink Price Feed
- brownie-config
- SPDX
- Matching Units of Measure
- Can't just divide
- Test early and often
- Quick Math Sanity Check
- deleting networks
- Alchemy again
- Enum
startLottery- Openzeppelin... Is this the first openzeppelin reference?
- Openzeppelin Contracts Github
- Randomness
- Pseudorandomness
blockkeywordblock.difficultyblock.timestamp
keccack256- True Randomness with Chainlink VRF
- VRFConsumerBase.sol
- Chainlink VRF Remix Version
- Inheriting Constructors
- Oracle Gas & Transaction Gas
- Why didn't we pay gas on the price feeds?
- Chainlink Node Fees
- Request And Receive Introduction
- Kovan Faucets
- Funding Chainlink Contracts
- Request And Receive Explanation
- A Clarification
endLotteryreturns (type variableName)fulfillRandomnessoverride- Modulo Operation (Mod Operation %)
- Paying the lottery winner
- Resetting the lottery
Testing Lottery.sol
deploy_lottery.pyget_account()refactoredget_contractcontract_to_mockContract.from_abi
- Adding the parameters to deploying to lottery
vrfCoordinatorMockand adding mocksLinkTokenand Mocks- Successful Ganache Deployment!
- Python Lottery Scripts/Functions
start_lottery- Brownie tip: Remember to
tx.wait(1)your last transaction enter_lotteryend_lottery
- Funding with LINK
- brownie interfaces
- Waiting for callback
- Integration Tests & Unit Tests
- Test all lines of code
test_get_entrance_feepytest.skip(again)test_cant_enter_unless_startedtest_can_start_and_enter_lotterytest_can_pick_winner_correctly- Events and Logs
callBackWithRandomness
Lottery.sol Testnet Deployment
topics- conftest.py
Lesson 8: Chainlink Mix
š» Code: https://github.com/smartcontractkit/chainlink-mix
Brownie Mixes
Lesson 9: ERC20s, EIPs, and Token Standards
š» Code: https://github.com/PatrickAlphaC/erc20-brownie-py
- ERC20/EIP20 Standard
- What is an ERC20?
- Creating an ERC20
- OpenZeppelin ERC20
- Solidity 0.8
- I Challenge you to code this yourself!
deploy_token.py- Copy paste
helpful_scripts.py - Viewing our token in metamask
- Adding to an exchange
Lesson 10: Defi & Aave
*NOTE: This repo is now archived as kovan is no longer supported. You can still follow along with the learning, but know the code may not work the same on a different testnet.
š» Code: https://github.com/PatrickAlphaC/aave_brownie_py_freecode
Defi Intro
- Defipulse
- Defillama
- Aave Testnet Site
- Paraswap
- Decentralized Exchange
Aave UI
- Kovan ETH
- What is Aave?
- Borrowing and Lending
- Connecting to Aave
- Depositing Tokens / Lending
- Checking your transaction is correct
- WETH Gateway
- Interest Bearing Token (aToken)
- Collateral
- DAI
- Stablecoin
- Wrapped Bitcoin (wBTC)
- Why borrow tokens?
- Blockchain Fintech Tutorial
- DISCLAIMER ABOUT BORROWING
- Borrowing Tokens
- Liquidations
- Your health factor must be above 1
- Solvent
- Stable vs Variable Interest Rate
- Repaying our borrows/loans
- Reward token / governance token
- Governance
Programmatic Interactions with Aave
- Quant Defi Engineer
- Aave Documentation
- Setup
- Converting ETH -> WETH
get_weth.py- IWETH
- Kovan WETH Token Address: 0xd0a1e359811322d97991e03f863a0c30c2cf029c
- Mainnet WETH Token Address: 0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2
- Converting WETH -> ETH with
withdraw aave_borrow.py- LendingPool
- LendingPoolAddressProvider
- LendingPool and LendingPoolAddressProvider Addresses
- Fixing import dependencies
- Aave Github
- ERC20 Approve Function
- IERC20 from Patrick's repo
deposit- getUserAccountData
- Liquidation Threshold
- Risk Parameters
- Borrowing DAI
- Getting DAI Conversion Rate
- borrow
- Mainnet DAI Address: 0x6b175474e89094c44da98b954eedeac495271d0f
- Aave Testnet Token Addresses
- Repaying
- Kovan Run
- Viewing the transactions
Testing
Lesson 11: NFTs
š» Code: https://github.com/PatrickAlphaC/nft-demo
Non-Technical Explainer
- End-to-end article
- What is an NFT?
- ERC721
- Token URI
- Token Metadata Example
- IPFS
Simple NFT
- brownie mix
- Initial Setup
SimpleCollectible.sol- OpenZeppelin ERC721
- Pug Image
- NFT Constructor
- NFT is a type of factory pattern
createCollectible_safeMint
- TokenURI & Metadata
- Opensea listing example
- Is this decentralized?
- Ethereum Size and dStorage
- You need to have your NFT attributes both on-chain and inside your tokenURI metadata
deploy_and_create.py- TokenURI used for the demo: https://ipfs.io/ipfs/Qmd9MCGtdVz2miNumBHDbvj8bigSgTwnr4SbyH6DNnpWdt?filename=0-PUG.json
- IPFS Companion
- Rinkeby Deployment
- Opensea Example
SimpleCollectible Testing
- What else with NFTs?
Advanced NFT
AdvancedCollectible.sol- Dungeons and Dragons Example
- Double Inherited Constructors
createCollectible(Advanced)tokenIdToBreed
- Working with in-flight Chainlink VRF requests
- Download the NFT images from the nft-mix
setTokenURI_isApprovedOrOwner
- Emit events when you update mappings
indexedevent keyword
Advanced deploy_and_create
- Move
OPENSEA_URLtohelpful_scripts - Deploying AdvancedCollectible
- Opensea testnet is only compatible with Rinkeby
- Rinkeby Chainlink VRF Contract Addresses
- Speeding through adding functions from previous projects
- Deploy to Rinkeby
create_collectible.py- A quick unit test
- A quick integration test
Creating Metadata & IPFS
create_metadata.pyget_breed- Metadata Folder
metadata_template- NFT Metadata Attributes
- Checking if Metadata file already exists
- Uploading to IPFS
upload_to_ipfs- Download IPFS Command Line
- Download IPFS Desktop
- HTTP IPFS Docs
ipfs daemon- Pinata
- Pinata Docs
- Refactoring to not re-upload to IPFS
- Setting the TokenURI
- End-To-End Manual Testnet Test
- Viewing on Opensea
Lesson 12: Upgrades
š» Code: https://github.com/PatrickAlphaC/upgrades-mix
Introduction to upgrading smart contracts
- Original Video
- Smart Contracts can be upgraded!
- Does this mean they are not immutable?
- Trail of Bits on Upgradeable Smart Contracts
- The "Not Really Upgrading" / Parameterization Method
- The Social Yeet / Migration Method
- Contract Migration
- Proxies
- DelegateCall
- Terminology:
- Implementation Contract
- Proxy Contract
- User
- Admin
- Gotchas:
- Storage Clashes
- Function Selector
- Function Selector Clashes
- Proxy Patterns:
- Transparent Proxy Pattern
- Universal Upgrade Proxy Standard
- Diamond/Multi-Facet Proxy
Upgrades-mix and code
- Setup
Box.solBoxV2.sol- Getting the proxy contracts
- Openzeppelin Proxy Github
01_deploy_box.py- Hooking up a proxy to our implementation contract
- (Optional) Creating a Gnosis Safe
- Initializers
- Encoding Initializer Function
- Assigning ABI to a proxy
- Running the script
- Upgrade Python Function
Testing Upgrades
- Testing our proxy
- Testing our upgrades
Upgrades on a testnet
Bonus Lesson 13: Full Stack Defi
Note: This section is archived as kovan is now deprecated. If you're looking to learn more Full-stack, check out the full stack portions of the hardhat/javascript video.
Link to hardhat/javascript video with more full-stack examples: https://github.com/smartcontractkit/full-blockchain-solidity-course-js
š» Code: https://github.com/PatrickAlphaC/defi-stake-yield-brownie-freecode
- FreeCodeCamp React
- What are we building?
- Setup
DappToken.solTokenFarm.soltokenIsAllowedaddAllowedTokens- mapping of a mapping
stakeTokensissueTokensgetUserTotalValuegetUserSingleTokenValuegetTokenValuesetPriceFeedContractunStakeTokens- Can this be reentrancy attacked?
Defi Stake Yield Brownie Scripts & Tests
deploy.py- Deploying DappToken
- Deploying TokenFarm
- Adding allowed tokens
- ERC20 Kovan Faucet
- If the link above does not work, you can get another ERC20 token using this faucet: Weenus ERC20 Faucet
- Mocking our ERC20s
Testing our Defi Stake Yield Brownie Dapp
test_set_price_feed_contracttest_stake_tokens- Fixtures
test_issue_tokens- Now you try on tests!
Front End / Full Stack
- Front End Introduction
- Typescript
- React
- useDapp
- npx
- yarn
create-react-app- Layout
- Testing Front End
- yarn && yarn start
- Connecting our wallets
- Install useDapp
- Header Component
- Connect Button
- Material-UI
- Making our button nicer
Main.tsx- Sending
brownie-config&buildfolder to our UI - Helper Config
- TypeScript error suppression
- Getting addresses
- Ethers
- Only support kovan
- Sending
YourWalletsupportedTokens- State Hooks
- Showing tokens
WalletBalanceethersproject/unitsBalanceMsg- Stake Form
- Calling
approve useContractFunctionuseEffect- Notifications
- Make it pretty
- Alerts
Shoutout to Matt for the help on the front end!
Closing and Summary
Security
- Best Practices
- Attacks
- Damn Vulnerable Defi
- Ethernaut
- Some Auditors
Where do I go now?
Learning More
- CryptoZombies
- Dapp University
- ChainShot
- Ivan on Tech
- Eat the Blocks
- Patrick Collins
- Austin Griffith
- Nader Dabit
- Ethereum.org
Community
Hackathons
Be sure to check out project grant programs!
Vyper
And make today an amazing day!