This is a section of the Cyfrin Foundry Solidity Course. ⭐️ (3:04:09) | Lesson 9: Foundry Smart Contract Lottery

• Chanilink VRF: to obtain a random number.
• Chainlink Automation: to automate the previous task and designate a winner.

vfr & upkeep id: 9316 / 80069385047514437119098851493706281179579006106039620986720070128060228298507

• Foundry Smart Contract Lottery
• Getting Started
  • Requirements
  • Quickstart
• Usage
  • Start a local node
  • Library
  • Deploy
  • Deploy - Other Network
  • Testing
    • Test Coverage
• Deployment to a testnet or mainnet
  • Scripts
  • Estimate gas
• Formatting
• Thank you!

• git
  • You'll know you did it right if you can run git --version and you see a response like git version x.x.x
• foundry
  • You'll know you did it right if you can run forge --version and you see a response like forge 0.2.0 (816e00b 2023-03-16T00:05:26.396218Z)

clone the repository, then :

cd foundry-smart-contract-lottery
forge build

make anvil

If you're having a hard time installing the chainlink library, you can optionally run this command.

forge install smartcontractkit/[email protected] --no-commit

This will default to your local node. You need to have it running in another terminal in order for it to deploy.

make deploy

See below

We talk about 4 test tiers in the video.

1. Unit
2. Integration
3. Forked
4. Staging

This repo we cover #1 and #3.

forge test

or

forge test --fork-url $SEPOLIA_RPC_URL

forge coverage

1. 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.

1. Get testnet ETH

Head over to faucets.chain.link and get some testnet ETH. You should see the ETH show up in your metamask.

2. 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.

3. 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.

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"

You can estimate how much gas things cost by running:

forge snapshot

And you'll see an output file called .gas-snapshot

To run code formatting:

forge fmt