You're reading from Architecting ASP.NET Core Applications An atypical design patterns guide for .NET 8, C# 12, and beyond

Product type Paperback

Published in Mar 2024

Publisher Packt

ISBN-13 9781805123385

Length 806 pages

Edition 3rd Edition

Languages

Tools

.NET

Concepts

Design Patterns

Author (1):

Carl-Hugo Marcotte

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Table of Contents (27) Chapters

Preface

1. Section 1: Principles and Methodologies FREE CHAPTER

2. Introduction

3. Automated Testing

4. Architectural Principles

5. REST APIs

6. Section 2: Designing with ASP.NET Core

7. Minimal APIs

8. Model-View-Controller

9. Strategy, Abstract Factory, and Singleton Design Patterns

10. Dependency Injection

11. Application Configuration and the Options Pattern

12. Logging Patterns

13. Section 3: Component Patterns

14. Structural Patterns

15. Behavioral Patterns

16. Operation Result Pattern

17. Section 4: Application Patterns

Anti-pattern – Big Ball of Mud

18. Layering and Clean Architecture

19. Object Mappers

20. Mediator and CQS Patterns

21. Getting Started with Vertical Slice Architecture

22. Request-EndPoint-Response (REPR)

23. Introduction to Microservices Architecture

24. Modular Monolith

25. Other Books You May Enjoy

26. Index

Revisiting the Singleton pattern

The Singleton pattern is obsolete, goes against the SOLID principles, and we replace it with a lifetime, as we’ve already seen. This section explores that lifetime and recreates the good old application state, which is nothing more than a singleton-scoped dictionary.

We explore two examples: one about the application state, in case you were wondering where that feature disappeared to. Then, the Wishlist project also uses the singleton lifetime to provide an application-level feature. There are also a few unit tests to play with testability and to allow safe refactoring.

Project – Application state

You might remember the application state if you programmed ASP.NET using .NET Framework or the “good” old classic ASP with VBScript. If you don’t, the application state was a key/value dictionary that allowed you to store data globally in your application, shared between all sessions and requests. That is one...