Real-world Node.js Projects

const express = require("express");
const mongoose = require("mongoose");
const bcrypt = require("bcryptjs");
const jwt = require("jsonwebtoken");

const app = express();
app.use(express.json());

// Connect MongoDB
mongoose.connect("mongodb://localhost:27017/blog");

// Schema
const postSchema = new mongoose.Schema({
  title: String,
  content: String,
  author: { type: mongoose.Schema.Types.ObjectId, ref: "User" },
});

const Post = mongoose.model("Post", postSchema);

// Routes
app.get("/api/posts", async (req, res) => {
  const posts = await Post.find().populate("author", "name");
  res.json(posts);
});

app.post("/api/posts", authenticate, async (req, res) => {
  const post = await Post.create({
    ...req.body,
    author: req.user.id,
  });
  res.status(201).json(post);
});

app.listen(3000);

const express = require("express");
const http = require("node:http");
const { Server } = require("socket.io");

const app = express();
const server = http.createServer(app);
const io = new Server(server);

io.on("connection", (socket) => {
  console.log("User connected:", socket.id);

  socket.on("chat-message", (msg) => {
    io.emit("chat-message", msg); // broadcast
  });

  socket.on("disconnect", () => {
    console.log("User disconnected:", socket.id);
  });
});

server.listen(3000);

const express = require("express");
const multer = require("multer");
const path = require("node:path");

const app = express();

// storage config
const storage = multer.diskStorage({
  destination: "uploads/",
  filename: (req, file, cb) => {
    const unique = Date.now() + path.extname(file.originalname);
    cb(null, unique);
  },
});

const upload = multer({
  storage,
  limits: { fileSize: 5 * 1024 * 1024 }, // 5MB
  fileFilter: (req, file, cb) => {
    const allowed = /jpeg|jpg|png|gif/;
    const ext = allowed.test(path.extname(file.originalname));
    cb(null, ext);
  },
});

app.post("/upload", upload.single("image"), (req, res) => {
  res.json({ file: req.file });
});

app.listen(3000);