This chapter covers essential frameworks and techniques for building web applications and performing web scraping with Python. It introduces you to popular tools used to create APIs, handle HTTP requests, serve dynamic content, and scrape data from websites efficiently and ethically.
Flask: Lightweight Web Framework
- Microframework designed for simplicity and flexibility
- Easy routing setup to define URL endpoints
- Supports templating engines like Jinja2 for dynamic HTML
- Handles GET, POST, and other HTTP methods seamlessly
- Integrates with databases and supports session management
- Rich ecosystem with extensions for authentication, forms, and more
- Great for prototyping and building small to medium web apps
- Extensive documentation and community support
- Example-driven tutorials for RESTful API development
- Debugging and testing tools integrated for development ease
Django: Full-Featured Web Framework
- High-level framework for rapid development and clean design
- Built-in ORM for database operations and migrations
- Automatic admin interface for managing data
- URL routing, templating, and form handling out of the box
- Robust authentication and user management system
- Supports middleware, signals, and reusable apps
- Scalable architecture for large and complex projects
- Strong security features to prevent common web vulnerabilities
- Comprehensive documentation and active community
- Ideal for building content management systems and enterprise apps
FastAPI: Modern, High-Performance API Framework
- Asynchronous framework designed for speed and performance
- Built on Starlette for async support and Pydantic for data validation
- Automatic OpenAPI (Swagger) documentation generation
- Supports dependency injection and security features
- Uses Python type hints for input validation and serialization
- Ideal for building scalable, production-ready APIs
- Easy integration with databases, OAuth2, and WebSockets
- Encourages clean code with modular design
- Strong typing reduces runtime errors and improves code quality
- Supports background tasks, event handlers, and middleware
Web Scraping: Extracting Data from the Web
- Programmatically downloading and parsing HTML pages
- Using
requests library to fetch page content
- BeautifulSoup for parsing and navigating HTML/XML structures
- Handling JavaScript-rendered content using Selenium or Playwright
- Techniques to handle pagination, forms, and login-required pages
- Data cleaning and transformation after extraction
- Storing scraped data in CSV, JSON, or databases
- Rate limiting and respect for robots.txt to avoid server overload
- Legal and ethical considerations in web scraping
- Examples on scraping dynamic sites and APIs