Database Integration

• Topic: "Working with Databases: MongoDB and Mongoose"
• Description: Introduction to MongoDB and Mongoose for database integration in Node.js applications.

Content:

1. Introduction to MongoDB

• What is MongoDB: Explain MongoDB as a NoSQL database.
• Why MongoDB: Discuss the benefits like flexibility, scalability, and performance.

2. Setting Up MongoDB

• Installation: Provide links and instructions for installing MongoDB locally or using a service like MongoDB Atlas.

• Connecting to MongoDB:
  

  const mongoose = require('mongoose');
  
  mongoose.connect('mongodb://localhost:27017/mydatabase', {
    useNewUrlParser: true,
    useUnifiedTopology: true
  }).then(() => {
    console.log('Connected to MongoDB');
  }).catch(err => {
    console.error('Connection error', err);
  });
  

3. Defining a Schema with Mongoose

• Install Mongoose:
  

  npm install mongoose
  

• Define a Book Schema:
  

  const bookSchema = new mongoose.Schema({
    title: String,
    author: String,
    publishedDate: Date,
    pages: Number
  });
  
  const Book = mongoose.model('Book', bookSchema);
  

4. CRUD Operations with Mongoose

• Create Operation:
  

  app.post('/books', async (req, res) => {
    const book = new Book(req.body);
    try {
      await book.save();
      res.status(201).json(book);
    } catch (err) {
      res.status(400).json({ error: err.message });
    }
  });
  

• Read Operations:
  

  app.get('/books', async (req, res) => {
    try {
      const books = await Book.find();
      res.json(books);
    } catch (err) {
      res.status(500).json({ error: err.message });
    }
  });
  
  app.get('/books/:id', async (req, res) => {
    try {
      const book = await Book.findById(req.params.id);
      if (book) {
        res.json(book);
      } else {
        res.status(404).send('Book not found');
      }
    } catch (err) {
      res.status(500).json({ error: err.message });
    }
  });
  

• Update Operation:
  

  app.put('/books/:id', async (req, res) => {
    try {
      const book = await Book.findByIdAndUpdate(req.params.id, req.body, { new: true });
      if (book) {
        res.json(book);
      } else {
        res.status(404).send('Book not found');
      }
    } catch (err) {
      res.status(400).json({ error: err.message });
    }
  });
  

• Delete Operation:
  

  app.delete('/books/:id', async (req, res) => {
    try {
      const book = await Book.findByIdAndDelete(req.params.id);
      if (book) {
        res.status(204).send();
      } else {
        res.status(404).send('Book not found');
      }
    } catch (err) {
      res.status(500).json({ error: err.message });
    }
  });
  

5. Testing with Postman

• Repeat Testing: Demonstrate testing the CRUD operations with Postman or Curl.