Exploring Fuel Network.

Intro

Aptos is a layer 2 modular execution layer for ethereum.

Why are we scaling ethereum using layer 2.

It always feels like Ethereum is that layer 1 blockchain that everyone's trying so hard to scale but it's fundamentally meant to be slow. Shouldn't we try to put a lot of effort in improving the base layer instead of figuring out million ways to come up with various layer 2 and sidechain to scale it.

Simplest smart contract development lifecycle on Fuel network.

Install the fuel core and other utilities from fuel blockchain that are needed for development.

# Install forc and fuel core.
cargo install forc fuel-core

# Sway Formatter
cargo install forc-fmt

# Block Explorer
cargo install forc-explore

# Sway Language Server
cargo install forc-lsp

Install a vscode extension for sway lang.

https://marketplace.visualstudio.com/items?itemName=FuelLabs.sway-vscode-plugin

Writing a simple contract that increment a variable.

contract;

storage {
    counter: u64 = 0,
}

abi Counter {
    #[storage(read, write)]
    fn increment();

    #[storage(read)]
    fn count() -> u64;
}

impl Counter for Contract {
    #[storage(read, write)]
    fn increment() {
        storage.counter = storage.counter + 1;
    }

    #[storage(read)]
    fn count() -> u64 {
        storage.counter
    }
}

Creating an account using forc-wallet

Read the docs to learn more about it https://github.com/FuelLabs/forc-wallet#forc-wallet and use https://faucet-beta-1.fuel.network/ for faucet to get some test ether on fuel network.

Deploy the contract using the following command.

forc deploy --url https://node-beta-1.fuel.network/graphql --gas-price 1

Also you'll have to sign the transaction and then provide the signed transaction so use the following comand.

forc wallet sign <transaction-id> 0

Building simplest frontend.

Create a simple react app using CRA, then install fuels, typechain-target-fuels, then type the following command to generate types from your abi from compiled contracts. Make sure to adjust directoris according to your file structure.

npx fuelchain --target=fuels --out-dir=./src/contracts ../counter/out/debug/*-abi.json

You'll need to create a demo account to sign this transation so use the fuels module to do it.

const { Wallet } = require("fuels");

const wallet = Wallet.generate();

console.log("address", wallet.address.toString());
console.log("private key", wallet.privateKey);

Then use this in App.tsx to get the counter and update it.

import { Wallet } from "fuels";
import { useEffect, useState } from "react";

import { CounterAbi__factory } from "../src/contracts";
const CONTRACT_ID =
  "0x5c3db2421a155265b7e415ab9c406ff4664bcad29fd99990b55e315832325beb";
const WALLET_SECRET = "<a-private-key-goes-here>";
const wallet = new Wallet(
  WALLET_SECRET,
  "https://node-beta-1.fuel.network/graphql"
);
const contract = CounterAbi__factory.connect(CONTRACT_ID, wallet);

export default function App() {
  const [counter, setCounter] = useState<number>();
  const [loading, setLoading] = useState(false);

  useEffect(() => {
    (async () => {
      console.log("Setting value");
      const { value } = await contract.functions.count().get();
      setCounter(Number(value));
    })();
  }, []);
  async function increment() {
    // a loading state
    setLoading(true);
    // Creates a transactions to call the increment function
    // because it creates a TX and updates the contract state this requires the wallet to have enough coins to cover the costs and also to sign the Transaction
    try {
      await contract.functions.increment().txParams({ gasPrice: 1 }).call();
      const { value } = await contract.functions.count().get();
      setCounter(Number(value));
    } finally {
      setLoading(false);
    }
  }
  return (
    <>
      <h1>Fuel me ⛽️</h1>

      <p>Wallet: {wallet.address.toString()}</p>

      <br />

      <p>
        <strong>Counter:</strong> {counter}
      </p>
      <div>
        <button disabled={loading} onClick={increment}>
          {loading ? "Incrementing..." : "Increment"}
        </button>
      </div>
    </>
  );
}

That's it, you got a gist of how to work on fuel network, BTW I did this on a stream as well you can check that here and you can follow my twitch account and join me on the quest of finding amazing web3 tools to write the next billion dollar financial tools.