This demo shows how to use Chainlink Keepers to automate funding an NFT contract so random collectibles can be created in a decentralized manner.
Please install or have installed the following:
- Install Brownie, if you haven't already. Here is a simple way to install brownie.
python3 -m pip install --user pipx
python3 -m pipx ensurepath
# restart your terminal
pipx install eth-brownieOr, if that doesn't work, via pip
pip install eth-brownie- Download the mix and install dependancies.
brownie bake chainlink-mix
cd chainlink-mix
pip install -r requirements.txtThis will open up a new Chainlink project. Or, you can clone from source:
git clone https://github.com/PatrickAlphaC/top-up-nft
cd top-up-nftIf you want to be able to deploy to testnets, do the following.
Set your WEB3_INFURA_PROJECT_ID, and PRIVATE_KEY environment variables.
You can get a WEB3_INFURA_PROJECT_ID by getting a free trial of Infura. At the moment, it does need to be infura with brownie. If you get lost, you can follow this guide to getting a project key. You can find your PRIVATE_KEY from your ethereum wallet like metamask.
You'll also need testnet ETH and LINK. You can get LINK and ETH into your wallet by using the faucets located here. If you're new to this, watch this video.. Look at the rinkeby and kovan sections for those specific testnet faucets.
You can add your environment variables to a .env file. You can use the .env.exmple as a template, just fill in the values and rename it to '.env'. Then, uncomment the line # dotenv: .env in brownie-config.yaml
Here is what your .env should look like:
export WEB3_INFURA_PROJECT_ID=<PROJECT_ID>
export PRIVATE_KEY=<PRIVATE_KEY>
AND THEN RUN source .env TO ACTIVATE THE ENV VARIABLES
(You'll need to do this everytime you open a new terminal, or learn how to set them easier)
WARNING
DO NOT SEND YOUR PRIVATE KEY WITH FUNDS IN IT ONTO GITHUB
Otherwise, you can build, test, and deploy on your local environment.
You'll need to register your contract with the Chainlink keeper network in order for this to function correctly on the keeper network.
Please see the Chainlink Keeper documentation on how to do this.
For local testing install ganache-cli
npm install -g ganache-clior
yarn add global ganache-clibrownie run scripts/collectible/deploy.py --network kovanThen, after registering with the keeper network, you'll automatically add LINK token to your contract. Then you can create collectibles with:
brownie run scripts/collectible/create_collectible.py
For local development, you might want to deploy mocks. You can run the script to deploy mocks. Depending on your setup, it might make sense to not deploy mocks if you're looking to fork a mainnet. It all depends on what you're looking to do though. Right now, the scripts automatically deploy a mock so they can run.
brownie test
For more information on effective testing with Chainlink, check out Testing Smart Contracts
Tests are really robust here! They work for local development and testnets. There are a few key differences between the testnets and the local networks. We utilize mocks so we can work with fake oracles on our testnets.
brownie testpip install black
pip install autoflake
autoflake --in-place --remove-unused-variables --remove-all-unused-imports -r .
black .
To get started with Brownie:
- Chainlink Documentation
- Check out the Chainlink documentation to get started from any level of smart contract engineering.
- Check out the other Brownie mixes that can be used as a starting point for your own contracts. They also provide example code to help you get started.
- "Getting Started with Brownie" is a good tutorial to help you familiarize yourself with Brownie.
- For more in-depth information, read the Brownie documentation.
Any questions? Join our Discord
This project is licensed under the MIT license.