Flask Tutorial

Flask is a lightweight web framework used to build web applications and APIs. It follows a minimal design and provides core features like routing, request handling and template rendering while allowing developers to add extensions as needed. It is widely used for building small to medium web applications due to its simplicity and flexibility.

• Microframework: Lightweight framework with minimal dependencies, giving developers full control over application structure.
• Werkzeug & Jinja2: Uses Werkzeug for request/response handling and Jinja2 for dynamic HTML templating.
• Routing: Maps URLs to Python functions using simple decorators.
• Flexible Database Choice: No built-in ORM, allowing use of tools like SQLAlchemy or raw SQL.
• API Development: Well-suited for building RESTful APIs and backend services.
• Development Server: Includes a built-in server for local testing during development.

Introduction

This section introduces Flask, compares it with Django and shows how to install it on Windows to start building web applications.

• Basics & Installation
• Django vs Flask

Quick Start

Covers creating and running a basic Flask app, understanding routes, HTTP methods, variables, redirects and basic configurations.

• First App
• Running an App
• Routes
• Models
• HTTP Method
• Variable Rules
• Redirect and Errors
• Change Port
• Changing Host IP Address

Templates and Static Files

Explains creating dynamic web pages using templates and managing static files like CSS, JavaScript and images.

• Templates
• Template Inheritance
• Static Files

Form Handling

This section covers capturing user input, form validation, file uploads and security features like CSRF protection.

• Flask-WTF
• Handling File Uploads
• CSFR Protection

Configuration

It explains how to manage application settings such as debug mode, secret keys and environment-based configurations.

• App Configuration
• Environment-Specific Configuration

Database

Flask supports multiple databases for storing and managing data, including SQLite, PostgreSQL, MySQL, MongoDB and also allows using SQLAlchemy or executing raw SQL queries.

• SQLAlchemy
• SQLite
• MongoDB Database
• PostgreSQL Database
• Login & Registration Project MySQL
• Execute Raw SQL in SQLAlchemy

Middlewares

This section covers how middleware processes requests and responses for tasks like logging, authentication and modifications.

• Middlewares
• WSGI Middleware

Authentication

Authentication is used to verify user identity and manage secure access to applications. It includes login systems, password hashing, session management and permission control.

• Adding Authentication
• Display Current Username
• Password Hashing with Bcrypt
• Store username and password
• Role-Based Access Control
• Sessions to server Logout
• JWT
• Cookies
• JSON Response

Rest APIs

Flask makes building REST APIs easy by handling requests like GET, POST, PUT and DELETE. With Flask-RESTful, one can send and receive JSON data, manage authentication and secure the API.

• Creating Rest APIs
• RESTful Extension
• Serialization and Deserialization

Advanced Topics

Introduces advanced concepts like asynchronous programming, WebSockets and modular app structure using blueprints.

• Asynchronous Programming
• Web Sockets
• Blueprints

Deployment & Error Handling

After development, Flask apps must be deployed and properly handle errors. This section covers deployment methods and techniques for managing application errors.

• Subdomain
• Handling 404 Error
• Dockerization
• Deploying App on Heroku
• Deploying ML Model

Projects

This section includes practical Flask projects that demonstrate real-world applications such as portfolio websites, APIs, data visualization and sentiment analysis tools.

• Todo List App
• Single Page Portfolio
• Profile Application
• Wikipedia Search App
• Twitter Sentiment Analysis
• Cricket Score API using Web Scraping
• Adding Graphs to Flask Apps
• Projects Archives 

Additional Resources

This section provides helpful articles and references to deepen understanding of Flask and related topics.

• Career Opportunities
• Interview Questions and Answers