Sample ERC-712 implementation

Description

This repository has followed this tutorial to create a simple ERC-712 implementation but has evolved a bit since then. The ERC-712 is an interface which defines how Non-fungible tokens (NFT) are implemented.

Prerequisites

• yarn
• Truffle npm install truffle -g or yarn global add truffle
• Ganache
• MetaMask Browser Extension or any other wallet capable of connecting to a local ethereum network

Hint: If you are using Visual Studio Code with the Solidity Extension you might need to adjust some settings: https://github.com/juanfranblanco/vscode-solidity#openzeppelin)

Install

After cloning this repository run: yarn install

If you are using windows and run into the issue that the openzepplin imports are not importing please open the project using WSL2 and try again

Run

First you need to start Ganache and copy a private key and import it into MetaMask. Keep Ganache running in the background. You will need to configure the local blockchain created by Ganache into MetaMask.

Deploy the smart contract: truffle migrate

Run the frontend: yarn serve

You should get prompted by MetaMask to connect a Wallet to this application. After connecting your wallet you can enter a new Color Hexcode into the field and hit "MINT". You should get prompted by MetaMask to confirm the transaction

Additional Commands:

To run the tests: truffle test

To overwrite the current deployed contract after a change: truffle migrate --reset

Deployment

To deploy this project to a public network you have to do some stuff. Deployment on the public test network ropsten is already preconfigured but a secrets.json is required at the root of the project. This file needs to look like this:

{ 
    "mnemonic": "<your-mnemonic>",
    "endpoint": "<your-project-endpoint>"
}

To generate a mnemonic you can run the command npx mnemonics. This will generate a phrase for you. Put the generated phrase into the mnemonic. It will look something like this: siege unaware display comic ball sing above view cradle alter chaos idea. The mnemonic is used to generate some wallet keys.

For deployment you will need some funds within your wallet. For public test networks you can use a faucet. I used this faucet for the ropsten test network. Receiving funds might differ from network to network. On this site you have to enter a public adress that you can get using your mnemonic. For the ropsten network enter the truffle console using truffle console --network ropsten. After entering the console run web3.eth.getAccounts(). You should see a list of adresses. Take the first and enter it into the faucet. After some time you should receive a bit of ETH. You can check your balance within the truffle console using web3.eth.getBalance("<wallet-address>")

Now your wallet it ready but you still need a node which can deploy the Smart Contract for you. For this i created an account on infura.io and created an Ethereum Project. After creating the project you should find a URL that looks something like this: wss://<public-network>.infura.io/ws/v3/<your-project-id>. Copy this and enter it into the endpoint field of your secrets.json.

Note: In theory you could also run your own node instead but i have no experience with it yet. :)

Now you are ready to deploy it! Go back into the truffle console using truffle console --network ropsten and run truffle migrate. After the process has finished you can get the address of the smart contract by using let c = await Color.deployed() followed by Color.address.

Don't forget to import the account you generated with the mnemonics into Metamask and switch to the network you deployed to.

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Hint: The /abis/Color.json folder retains the address of the Smart Contract on each different network.

Hint: If you want to use a different network other than ropsten you need to add it to truffle-config.js. You can use the ropsten configuration as a template

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Potential extensions:

• Owner of token can transfer it (webclient)
• Token owner can create offer or receive offer for their token

Interesting links:

• ERC721 interface: http://erc721.org/
• OpenZepplin library: https://github.com/OpenZeppelin/openzeppelin-contracts
• Truffle suite: https://www.trufflesuite.com/
• Deploying on a test network: https://www.youtube.com/watch?v=roHoOZXIxYs