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Build a Full-Stack Image Upload App with Node.js, Express, React, and Vite (Beginner Tutorial)

 If you’re new to full-stack web development and want a hands-on project to practice React frontend integration with a + Express backend, this tutorial is for you. In this guide, we’ll walk through a simple but powerful app that lets users upload images, store them on the server, and display them back in the browser.

This project is based on my GitHub repo: . It’s designed to be beginner-friendly, SEO-optimized, and a great starting point for anyone learning JavaScript full-stack development.

🛠️ Technologies Used

Here’s the tech stack powering this project:

  • – JavaScript runtime for the backend.

  • – Lightweight web framework for building REST APIs.

  • Multer – Middleware for handling file uploads.

  • CORS – Enables cross-origin requests between frontend and backend.

  • – Frontend library for building user interfaces.

  • Vite – Fast development server and build tool for React.

  • Fetch API – For making HTTP requests from the frontend.

🎯 Intent of Building This Project

The goal of this project is to:

  • Teach beginners how to connect a React frontend with a backend.

  • Demonstrate how to handle file uploads using Multer.

  • Provide a starter template for building full-stack apps with REST APIs.

  • Show how to integrate frontend-backend communication without running into CORS issues.

⚙️ Backend Setup (Node.js + Express)

The backend provides REST API endpoints for uploading and retrieving images.

Install dependencies


npm install express multer cors


import express from "express";
import cors from "cors";
import multer from "multer";

const app = express();
const PORT = 3000;

// Enable CORS
app.use(cors());

// Configure Multer for file storage
const storage = multer.diskStorage({
  destination: (req, file, cb) => cb(null, "uploads"),
  filename: (req, file, cb) => cb(null, Date.now() + "-" + file.originalname),
});
const upload = multer({ storage });

// Simple test endpoint
app.get("/api/hello", (req, res) => {
  res.json({ message: "Hello World!" });
});

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

// List uploaded images
import fs from "fs";
app.get("/api/images", (req, res) => {
  fs.readdir("uploads", (err, files) => {
    if (err) return res.status(500).json({ error: err });
    res.json({ images: files });
  });
});

app.listen(PORT, () => console.log(`Backend running on http://localhost:${PORT}`));

🎨 Frontend Setup (React + Vite)

The frontend provides a simple UI for selecting and uploading files.

Install dependencies


npm create vite@latest frontend
cd frontend
npm install


import React, { useState } from "react";

function App() {
  const [file, setFile] = useState(null);
  const [message, setMessage] = useState("");

  const handleUpload = async () => {
    const formData = new FormData();
    formData.append("file", file);

    const response = await fetch("http://localhost:3000/api/upload", {
      method: "POST",
      body: formData,
    });

    const data = await response.json();
    setMessage(`File uploaded: ${data.file.filename}`);
  };

  return (
    <div>
      <h1>React + Node.js File Upload</h1>
      <input type="file" onChange={(e) => setFile(e.target.files[0])} />
      <button onClick={handleUpload}>Upload</button>
      <p>{message}</p>
    </div>
  );
}

export default App;

🔗 Connecting Frontend and Backend

To avoid CORS issues, configure Vite’s proxy in vite.config.js:


export default {
  server: {
    proxy: {
      "/api": "http://localhost:3000",
    },
  },
};

This ensures that API calls from React (/api/...) are forwarded to the backend running on port 3000.

📸 Displaying Uploaded Images

You can extend the frontend to fetch and display uploaded images:


const [images, setImages] = useState([]);

const fetchImages = async () => {
  const response = await fetch("/api/images");
  const data = await response.json();
  setImages(data.images);
};

useEffect(() => {
  fetchImages();
}, []);

return (
  <div>
    <h2>Uploaded Images</h2>
    {images.map((img, index) => (
      <img key={index} src={`http://localhost:3000/uploads/${img}`} alt={img} />
    ))}
  </div>
);

🧑‍💻 Why This Project Matters

  • Beginner-friendly: Perfect for those learning React + integration.

  • Practical use case: File uploads are common in real-world apps (profile pictures, documents, etc.).

  • Scalable foundation: You can extend this into a full photo gallery, cloud storage integration, or even an AI-powered image app.

✅ Conclusion

This project is a hands-on introduction to full-stack development using modern tools like React and Vite on the frontend, and + Express on the backend. By following this tutorial, you’ll learn how to handle file uploads, build REST APIs, and connect frontend and backend seamlessly.

👉 Check out the full repo here:

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