index.js

import express from "express";
import bodyParser from "body-parser";

const app = express();
const port = 4000;

// In-memory data store
let posts = [
  {
    id: 1,
    title: "The Rise of Decentralized Finance",
    content:
      "Decentralized Finance (DeFi) is an emerging and rapidly evolving field in the blockchain industry. It refers to the shift from traditional, centralized financial systems to peer-to-peer finance enabled by decentralized technologies built on Ethereum and other blockchains. With the promise of reduced dependency on the traditional banking sector, DeFi platforms offer a wide range of services, from lending and borrowing to insurance and trading.",
    author: "Alex Thompson",
    date: "2023-08-01T10:00:00Z",
  },
  {
    id: 2,
    title: "The Impact of Artificial Intelligence on Modern Businesses",
    content:
      "Artificial Intelligence (AI) is no longer a concept of the future. It's very much a part of our present, reshaping industries and enhancing the capabilities of existing systems. From automating routine tasks to offering intelligent insights, AI is proving to be a boon for businesses. With advancements in machine learning and deep learning, businesses can now address previously insurmountable problems and tap into new opportunities.",
    author: "Mia Williams",
    date: "2023-08-05T14:30:00Z",
  },
  {
    id: 3,
    title: "Sustainable Living: Tips for an Eco-Friendly Lifestyle",
    content:
      "Sustainability is more than just a buzzword; it's a way of life. As the effects of climate change become more pronounced, there's a growing realization about the need to live sustainably. From reducing waste and conserving energy to supporting eco-friendly products, there are numerous ways we can make our daily lives more environmentally friendly. This post will explore practical tips and habits that can make a significant difference.",
    author: "Samuel Green",
    date: "2023-08-10T09:15:00Z",
  },
];

let lastId = 3;
const date = new Date();

// Middleware
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: true }));

// CHALLENGE 1: GET All posts
app.get('/posts', (req, res) => {
  res.json(posts);
});

// CHALLENGE 2: GET a specific post by id
app.get('/posts/:id', (req, res) => {
  const id = parseInt(req.params.id);
  const post = posts.find(post => post.id === id);
  if (!post) {
    return res.status(404).json({ error: `Post with id ${id} not found` });
  }
  res.json(post);
});

// CHALLENGE 3: POST a new post
app.post('/posts', (req, res) => {
  const { title, content, author } = req.body;
  if (!title || !content || !author) {
    return res.status(400).json({ error: 'Title, content, and author are required' });
  }
  const newPost = {
    id: ++lastId,
    title,
    content,
    author,
    date: new Date().toISOString(),
  };
  posts.push(newPost);
  res.status(201).json(newPost);
});

// CHALLENGE 4: PATCH a post when you just want to update one parameter
app.patch('/posts/:id', (req, res) => {
  const id = parseInt(req.params.id);
  const post = posts.find(post => post.id === id);
  if (!post) {
    return res.status(404).json({ error: `Post with id ${id} not found` });
  }

  const { title, content, author } = req.body;
  if (title) post.title = title;
  if (content) post.content = content;
  if (author) post.author = author;

  res.json(post);
});

// CHALLENGE 5: DELETE a specific post by providing the post id
app.delete('/posts/:id', (req, res) => {
  const id = parseInt(req.params.id);
  const postIndex = posts.findIndex(post => post.id === id);
  if (postIndex === -1) {
    return res.status(404).json({ error: `Post with id ${id} not found` });
  }
  posts.splice(postIndex, 1);
  res.sendStatus(204);
});

app.listen(port, () => {
  console.log(`API is running at http://localhost:${port}`);
});