Awesome
! Updates from Video
- V2.5 of Chainlink VRF uses a
uint256
as a subId instead of auint64
this repo has a comment to reflect that. We added a mock in case you'd like to work with version 2.5.- We use
0.1.0
of thefoundry-devops
package which doesn't need to haveffi=true
Foundry Smart Contract Lottery
This is a section of the Cyfrin Foundry Solidity Course.
⭐️ (3:04:09) | Lesson 9: Foundry Smart Contract Lottery
- Foundry Smart Contract Lottery
- Getting Started
- Usage
- Deployment to a testnet or mainnet
- Formatting
- Additional Info:
- Thank you!
Getting Started
Requirements
- git
- You'll know you did it right if you can run
git --version
and you see a response likegit version x.x.x
- You'll know you did it right if you can run
- foundry
- You'll know you did it right if you can run
forge --version
and you see a response likeforge 0.2.0 (816e00b 2023-03-16T00:05:26.396218Z)
- You'll know you did it right if you can run
Quickstart
git clone https://github.com/Cyfrin/foundry-smart-contract-lottery-cu
cd foundry-smart-contract-lottery-cu
forge build
Optional Gitpod
If you can't or don't want to run and install locally, you can work with this repo in Gitpod. If you do this, you can skip the clone this repo
part.
Usage
Start a local node
make anvil
Library
If you're having a hard time installing the chainlink library, you can optionally run this command.
forge install smartcontractkit/chainlink-brownie-contracts@0.6.1 --no-commit
Deploy
This will default to your local node. You need to have it running in another terminal in order for it to deploy.
make deploy
Deploy - Other Network
Testing
We talk about 4 test tiers in the video.
- Unit
- Integration
- Forked
- Staging
This repo we cover #1 and #3.
forge test
or
forge test --fork-url $SEPOLIA_RPC_URL
Test Coverage
forge coverage
Deployment to a testnet or mainnet
- Setup environment variables
You'll want to set your SEPOLIA_RPC_URL
and PRIVATE_KEY
as environment variables. You can add them to a .env
file, similar to what you see in .env.example
.
PRIVATE_KEY
: The private key of your account (like from metamask). NOTE: FOR DEVELOPMENT, PLEASE USE A KEY THAT DOESN'T HAVE ANY REAL FUNDS ASSOCIATED WITH IT.- You can learn how to export it here.
SEPOLIA_RPC_URL
: This is url of the sepolia testnet node you're working with. You can get setup with one for free from Alchemy
Optionally, add your ETHERSCAN_API_KEY
if you want to verify your contract on Etherscan.
- Get testnet ETH
Head over to faucets.chain.link and get some testnet ETH. You should see the ETH show up in your metamask.
- Deploy
make deploy ARGS="--network sepolia"
This will setup a ChainlinkVRF Subscription for you. If you already have one, update it in the scripts/HelperConfig.s.sol
file. It will also automatically add your contract as a consumer.
- Register a Chainlink Automation Upkeep
You can follow the documentation if you get lost.
Go to automation.chain.link and register a new upkeep. Choose Custom logic
as your trigger mechanism for automation. Your UI will look something like this once completed:
Scripts
After deploying to a testnet or local net, you can run the scripts.
Using cast deployed locally example:
cast send <RAFFLE_CONTRACT_ADDRESS> "enterRaffle()" --value 0.1ether --private-key <PRIVATE_KEY> --rpc-url $SEPOLIA_RPC_URL
or, to create a ChainlinkVRF Subscription:
make createSubscription ARGS="--network sepolia"
Estimate gas
You can estimate how much gas things cost by running:
forge snapshot
And you'll see an output file called .gas-snapshot
Formatting
To run code formatting:
forge fmt
Additional Info:
Some users were having a confusion that whether Chainlink-brownie-contracts is an official Chainlink repository or not. Here is the info.
Chainlink-brownie-contracts is an official repo. The repository is owned and maintained by the chainlink team for this very purpose, and gets releases from the proper chainlink release process. You can see it's still the smartcontractkit
org as well.
https://github.com/smartcontractkit/chainlink-brownie-contracts
Let's talk about what "Official" means
The "official" release process is that chainlink deploys it's packages to npm. So technically, even downloading directly from smartcontractkit/chainlink
is wrong, because it could be using unreleased code.
So, then you have two options:
- Download from NPM and have your codebase have dependencies foreign to foundry
- Download from the chainlink-brownie-contracts repo which already downloads from npm and then packages it nicely for you to use in foundry.
Summary
- That is an official repo maintained by the same org
- It downloads from the official release cycle
chainlink/contracts
use (npm) and packages it nicely for digestion from foundry.
Thank you!
If you appreciated this, feel free to follow me or donate!
ETH/Arbitrum/Optimism/Polygon/etc Address: 0x9680201d9c93d65a3603d2088d125e955c73BD65