/chainlinkHack

leom chainlinks

Primary LanguageAstro

JavaScript for Blockchain Developers.

https://cll-devrel.gitbook.io/javascript-for-blockchain-master-class/decentralized-news-service-contract

If this looks too tricky for you, check out: https://docs.chain.link/quickstarts/deploy-your-first-contract

Day 1: Build a simple decentralized news aggregator service

Following Richard's tutorial, the following was created:

Todo

  • Create a contract that uses Chainlink functions to get the latest news from hackernews api
  • Store the story on the blockchain
  • Display the stories on a webpage

Steps to run the project:

The contract is good to go and hooked up to Chainlink Functions Subscriber. To deploy and set up your Functions, you need to:

  • Compile and deploy the contract on a testnet (this is on Sepolia)

  • Create and fund a Chainlink Functions Subscription

  • Add your deployed contract address to your subscription as a "Consumer"

  • Add your subscription ID to the contract

  • Run the sendRequest function on the contract to get the latest news from Hackernews and save it to the blockchain

  • Call the getAllArticles function to get the latest news from the blockchain

    function getAllArticles() public view returns (string[] memory) {
        string[] memory allArticles = new string[](articles.length);
        for (uint i = 0; i < articles.length; i++) {
            allArticles[i] = string(articles[i].url);
        }
        return allArticles;
    }

  • in /src/pages/index.astro you can display the stories on a webpage

    async function fetchOGData(url) {
try {
  const response = await fetch(url);
  const html = await response.text();
  const dom = new JSDOM(html);
  const doc = dom.window.document;
  let ogTitle =
    doc.querySelector('meta[property="og:title"]')?.content || url;
  const ogImage = doc.querySelector('meta[property="og:image"]')?.content;
  return { ogTitle, ogImage, url };
} catch (error) {
  console.error("Error fetching OG data:", error);
  return { ogTitle: "No title", ogImage: "No image", url };
}

}



To get started quickly with this code, clone the repo, run `npm install` and `npm run dev`

nothing might show on the screen, why?

You need to create a `.env` file and have the following:

```bash
#### RPC for sepolia
PROVIDER_URL="https://rpc.sepolia.org"
CONTRACT_ADDRESS="your-contract-address"

Follow this article to get your contract ready and deployed.

This repo is just the frontend Dapp that interact with the smart contract using ether-js.