Django for Beginners Build websites with Python & Django   William S. Vincent   This book is for sale at http://leanpub.com/djangoforbeginners This version was published on 2022-03-24 *   *   *   *   * This is a Leanpub book. Leanpub empowers authors and publishers with the Lean Publishing process. Lean Publishing is the act of publishing an in-progress ebook using lightweight tools and many iterations to get reader feedback, pivot until you have the right book and build traction once you do. *   *   *   *   * © 2018 - 2022 William S. Vincent Table of Contents Introduction Why Django Why This Book Prerequisites Book Structure Book Layout Advice on Getting Stuck Community Conclusion Chapter 1: Initial Set Up The Command Line Shell Commands Install Python 3 on Windows Install Python 3 on Mac Python Interactive Mode Virtual Environments Install Django First Django Project Text Editors Install Git Conclusion Chapter 2: Hello World App Initial Set Up HTTP Request/Response Cycle Model-View-Controller vs Model-View-Template Create An App Hello, World Git GitHub SSH Keys Conclusion Chapter 3: Pages App Initial Set Up Templates Class-Based Views URLs About Page Extending Templates Tests Git and GitHub Local vs Production Heroku Deployment Checklist Conclusion Chapter 4: Message Board App Initial Set Up Create a Database Model Activating models Django Admin Views/Templates/URLs Adding New Posts Tests GitHub Heroku Configuration Heroku Deployment Conclusion Chapter 5: Blog App Initial Set Up Database Models Admin URLs Views Templates Static Files Individual Blog Pages Tests Git Conclusion Chapter 6: Forms CreateView UpdateView DeleteView Tests Conclusion Chapter 7: User Accounts Log In Updated Homepage Log Out Link Sign Up Sign Up Link GitHub Static Files Heroku Config Heroku Deployment SQLite vs PostgreSQL Conclusion Chapter 8: Custom User Model Initial Set Up Custom User Model Forms Superuser Conclusion Chapter 9: User Authentication Templates URLs Admin Tests Conclusion Chapter 10: Bootstrap Pages App Tests Testing Philosophy Bootstrap Sign Up Form Conclusion Chapter 11: Password Change and Reset Password Change Customizing Password Change Password Reset Custom Templates Try It Out Conclusion Chapter 12: Email SendGrid Custom Emails Conclusion Chapter 13: Newspaper App Articles App URLs and Views Detail/Edit/Delete Create Page Conclusion Chapter 14: Permissions and Authorization Improved CreateView Authorizations Mixins LoginRequiredMixin UpdateView and DeleteView Conclusion Chapter 15: Comments Model Admin Template Comment Form Comment View Comment Template Comment Post View Conclusion Chapter 16: Deployment Environment Variables DEBUG & ALLOWED HOSTS SECRET_KEY DATABASES Static Files Deployment Checklist GitHub Heroku Deployment Conclusion Conclusion Next Steps 3rd Party Packages Learning Resources Python Books Feedback Introduction Welcome to Django for Beginners, a project-based approach to learning web development with the Django web framework. In this book you will build five progressively more complex web applications, starting with a simple Hello, World app, progressing to a Pages app, a Message Board app, a Blog app with forms and user accounts, and finally a Newspaper app that uses a custom user model, email integration, foreign keys, authorization, permissions, and more. By the end of this book you should feel confident creating your own Django projects from scratch using current best practices. Django is a free, open source web framework written in the Python programming language. First released in 2005, Django has been in continuous development since then and today powers many of the largest websites in the world including Instagram, Pinterest, Bitbucket, and Disqus. At the same time, it is flexible enough to be a popular choice for early-stage startups and side projects. Why Django A “web framework” is a collection of tools that abstract away much of the difficulty–and repetition–inherent in web development. For example, most websites need the same basic functionality: the ability to connect to a database, set URL routes, display content on a page, handle security properly, and so on. Rather than recreate all of this from scratch, programmers over the years have created web frameworks in all the major programming languages: Django in Python, Rails in Ruby, and Laravel in PHP among many, many others. Django inherited Python’s “batteries-included” approach and includes out-of-the box support for common tasks in web development, including: user authentication testing database models, forms, URL routes, and templates admin interface security and performance upgrades support for multiple database backends This approach allows web developers to focus on what makes a web application unique rather than reinventing the wheel every time. In contrast, some web frameworks like Flask adopt a microframework approach of providing only the bare minimum required for a simple web page. Flask is far more lightweight than Django and allows for maximum flexibility, however this comes at a cost to the developer. To build even a basic website requires adding a dozen or more third-party packages, which may or may not be up-to-date. And the resulting Flask project structure often varies widely, making it more difficult to move between projects and maintain best practices within the community. Django remains under active development with a regular release schedule of monthly security/bug fixes and a major new release every 8 months. Millions of programmers have already used Django to build their websites. It doesn’t make sense to repeat the same code–and mistakes–when a large community of brilliant developers has already solved these problems for us. The Django community is also constantly adding new features and security improvements. And best of all, it’s written in the wonderfully readable yet still powerful Python programming language. In short, if you’re building a website from scratch Django is a fantastic choice. Why This Book I wrote this book because while Django is extremely well documented there is a severe lack of beginner-friendly tutorials available. When I first learned Django years ago, I struggled to even complete the official polls tutorial. Why was this so hard I remember thinking? With more experience, I now recognize that the writers of the Django docs faced a difficult choice: they could emphasize Django’s ease-of-use or its depth, but not both. They choose the latter and as a professional developer I appreciate the choice, but as a beginner I found it so… frustrating! My goal with this book is to fill in the gaps and showcase how beginner-friendly Django really can be. Prerequisites Django for Beginners is written for Django 4.0 and Python 3.10. All the code examples work with these versions. By the time you read this, there may be newer versions of both Django and Python available. In general, you should always strive to be on the latest version of Django and Python. As both are mature technologies, any issues that arise in the future as a result will be relatively minor. You don’t need previous Python or web development experience to complete this book. It is intentionally written so that even a total beginner can follow along and feel the magic of writing their own web applications from scratch. However, if you are serious about a career in web development, you will eventually need to invest the time to