Contracts

Before we start programming the frontend of the application, we need to compile the contracts and deploy them.

Compile

In the "Preparations" step, we prepared 2 contracts, our main application and a Proxy to work with ETH on the CKB layer. We'll compile them first.

Creation / Transfer

  • In the app root directory, create (if it doesn't already exist) a folder named contracts.

    cd <project-name>
mkdir contracts

  • Move the previously prepared contracts to this folder. The folder with contracts should look like this:

    • contracts/FancyNames.sol
    • contracts/SudtERC20Proxy.sol

Compile Script

Modify the package.json file so that you can compile contracts with a simple command.

  • add the command to the scripts object in this file
"compile": "truffle compile"
  • after making the change, the beginning of your package.json file should look similar to the example below.
{
  "name": "NervosDAPP",
  "version": "1.0.0",
  "private": true,
  "scripts": {
    "dev": "nuxt",
    "build": "nuxt generate",
    "start": "nuxt start",
    "compile": "truffle compile"
  },

  ...
  • Now we can compile the contracts. In the root of the project, execute the following code.
cd <project-name>
yarn compile

cd <project-name>
npm compile

Verification

If everything went well in the main directory of the project there should be a directory: build/contracts in which there are files:

  • build/contracts/Context.json
  • build/contracts/ERC20.json
  • build/contracts/FancyNames.json
  • build/contracts/IERC20.json

If something went wrong, retrace all steps.

Deploys

In the "Preparations" step, we prepared 2 contracts, our main application and a Proxy to work with ETH on the CKB layer. We'll compile them first.

Script

  • Create a file named deploy.js with the following content:

Carefully! You need to make some changes to this file.

  • The first is to replace the string in the code: <$CONTRACT$> with the following value:

    • ERC20.json – Proxy Contract
    • FancyNames.json – dApp Contract

  • If you are creating the deploy proxy contract, uncomment the line containing the arguments variable.

require('dotenv').config();

const Web3 = require('web3');
const { PolyjuiceHttpProvider, PolyjuiceAccounts } = require("@polyjuice-provider/web3");

const CompiledContractArtifact = require(`./build/contracts/<$CONTRACT$>`);

const polyjuiceConfig = {
    rollupTypeHash: process.env.ROLLUP_TYPE_HASH,
    ethAccountLockCodeHash: process.env.ETH_ACCOUNT_LOCK_CODE_HASH,
    web3Url: process.env.GODWOKEN_RPC_URL
};
  
const provider = new PolyjuiceHttpProvider(
    process.env.GODWOKEN_RPC_URL,
    polyjuiceConfig,
);

const web3 = new Web3(provider);

web3.eth.accounts = new PolyjuiceAccounts(polyjuiceConfig);
const account = web3.eth.accounts.wallet.add(process.env.ACCOUNT_PRIVATE_KEY);
web3.eth.Contract.setProvider(provider, web3.eth.accounts);

(async () => {
    console.log(`Using Ethereum address: ${account.address}`);

    const balance = BigInt(await web3.eth.getBalance(account.address));

    if (balance === 0n) {
        console.log(`Insufficient balance. Can't deploy contract. Please deposit funds to your Ethereum address: ${account.address}`);
        return;
    }

    console.log(`Deploying contract...`);

    const deployTx = new web3.eth.Contract(CompiledContractArtifact.abi).deploy({
        data: getBytecodeFromArtifact(CompiledContractArtifact),
        //arguments: [process.env.SUDT_NAME, process.env.SUDT_SYMBOL, process.env.SUDT_TOTAL_SUPPLY, process.env.SUDT_ID]
    }).send({
        from: account.address,
        to: '0x' + new Array(40).fill(0).join(''),
        gas: 6000000,
        gasPrice: '0',
    });

    deployTx.on('transactionHash', hash => console.log(`Transaction hash: ${hash}`));

    const receipt = await deployTx;

    console.log(`Deployed <$CONTRACT$>. Contract address: ${receipt.contractAddress}`);
})();

function getBytecodeFromArtifact(contractArtifact) {
    return contractArtifact.bytecode || contractArtifact.data?.bytecode?.object
}

The code for this file based from the source: https://github.com/Kuzirashi/gw-gitcoin-instruction/blob/master/src/examples/5-erc20-proxy/index.js

Run deploy.js

We have prepared the code and contracts, so we can deploy them to the network. Run the command below:

node deploy

You must execute this command 2 times. Appropriately modifying the .js file from above to the specific contract.

If you have funds on your private key and everything went well, you'll see the message like below:

[ririen@oad NervosDAPP]$ node deploy
Using Ethereum address: 0x5c5D5351aFAf7CdF5c2E7A826846e594B755d05b
Deploying contract...
Transaction hash: 0xf7ae1bb6df9e7abe3fed360df7235c02bed17d43a4041ffdc980d4ee8a4da859
Deployed ERC20.json. Contract address: 0xcda6d0D3C61a1d67CC502ffdbC20ad6Ec4cdE3B1


[ririen@oad NervosDAPP]$ node deploy
Using Ethereum address: 0x5c5D5351aFAf7CdF5c2E7A826846e594B755d05b
Deploying contract...
Transaction hash: 0xa13e4a5a6ec5d6a0cd03416d5c73956f5152cc6ff4d3e63366330c4129eb01de
Deployed FancyNames.json. Contract address: 0xFB5E7347bA0da2d7471E41FAE2308f3eeDE91288

Update .env

The contracts are now deployed, so the .env created earlier should be updated.

Complete the variables in the file: SUDT_PROXY_CONTRACT_ADDRESS and FANCY_CONTRACT_ADDRESS.

Environment Configuration