File Management System involves creating a Node.js and Express

Building a File Management System involves creating a Node.js and Express server that handles file upload, download, and deletion. Below is a step-by-step guide to create a simple File Management System.

Step 1: Set Up Your Project

1. Create a new project folder:

    mkdir file-management-system
    cd file-management-system
   

2. Initialize a new Node.js project:

    npm init -y
   

3. Install necessary dependencies:

    npm install express multer fs path
   

Step 2: Create Your Folder Structure

Create the following folder structure:

file-management-system/
|-- uploads/
|-- src/
|   |-- routes/
|       |-- files.js
|   |-- app.js
|-- server.js

Step 3: Set Up Express Server

In app.js, set up an Express server:

const express = require('express');
const path = require('path');
const filesRoutes = require('./routes/files');

const app = express();

app.use(express.static(path.join(__dirname, 'uploads')));
app.use('/files', filesRoutes);

module.exports = app;

Step 4: Create Routes for File Management

In routes/files.js, set up routes for file management:

const express = require('express');
const router = express.Router();
const multer = require('multer');
const fs = require('fs');
const path = require('path');

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

const upload = multer({ storage });

router.post('/upload', upload.single('file'), (req, res) => {
  res.json({ message: 'File uploaded successfully' });
});

router.get('/download/:filename', (req, res) => {
  const { filename } = req.params;
  const filePath = path.join(__dirname, '../uploads', filename);

  if (fs.existsSync(filePath)) {
    res.download(filePath);
  } else {
    res.status(404).json({ error: 'File not found' });
  }
});

router.delete('/delete/:filename', (req, res) => {
  const { filename } = req.params;
  const filePath = path.join(__dirname, '../uploads', filename);

  if (fs.existsSync(filePath)) {
    fs.unlinkSync(filePath);
    res.json({ message: 'File deleted successfully' });
  } else {
    res.status(404).json({ error: 'File not found' });
  }
});

module.exports = router;

Step 5: Run Your Application

In server.js, use the exported app to start the application:

const app = require('./src/app');

const PORT = process.env.PORT || 3000;

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

Start the server:

node server.js

Step 6: Test File Upload, Download, and Deletion

1. File Upload:

   Use a tool like Postman or Insomnia to send a POST request to http://localhost:3000/files/upload with a file attached. Ensure the file is sent with the key named file. You should receive a response indicating successful file upload.

2. File Download:

   Open your browser and navigate to http://localhost:3000/files/download/{filename}, replacing {filename} with the actual filename of the uploaded file. This should prompt a download of the file.

3. File Deletion:

   Use a tool like Postman or Insomnia to send a DELETE request to http://localhost:3000/files/delete/{filename}, replacing {filename} with the actual filename of the uploaded file. You should receive a response indicating successful file deletion.

Congratulations! You've created a simple File Management System with Node.js and Express. This example uses the multer middleware for file upload, and you can customize and extend it based on your specific requirements.