Book Image

An Atypical ASP.NET Core 6 Design Patterns Guide - Second Edition

By : Carl-Hugo Marcotte
5 (1)
Book Image

An Atypical ASP.NET Core 6 Design Patterns Guide - Second Edition

5 (1)
By: Carl-Hugo Marcotte

Overview of this book

An Atypical ASP.NET Core 6 Design Patterns Guide, Second Edition approaches programming like playing with LEGO®: snapping small pieces together to create something beautiful. Thoroughly updated for ASP.NET Core 6, with further coverage of microservices patterns, data contracts, and event-driven architecture, this book gives you the tools to build and glue reliable components together to improve your programmatic masterpieces. The chapters are organized based on scale and topic, allowing you to start small and build on a strong base, the same way that you would develop a program. You will begin by exploring basic design patterns, SOLID architectural principles, dependency injection, and other ASP.NET Core 6 mechanisms. You will explore component-scale patterns, and then move to higher level application-scale patterns and techniques to better structure your applications. Finally, you'll advance to the client side to connect the dots with tools like Blazor and make ASP.NET Core a viable full-stack web development framework. You will supplement your learning with practical use cases and best practices, exploring a range of significant Gang of Four (GoF) design patterns along the way. By the end of the book, you will be comfortable combining and implementing patterns in different ways, and crafting software solutions of any scale.
Table of Contents (31 chapters)
Preface
Free Chapter
1
Section 1: Principles and Methodologies
5
Section 2: Designing for ASP.NET Core
11
Section 3: Designing at Component Scale
15
Section 4: Designing at Application Scale
21
Section 5: Designing the Client Side
25
Acronyms Lexicon
26
Other Books You May Enjoy
27
Index
Appendices

Implementing the CQRS pattern

CQRS stands for Command Query Responsibility Segregation. We can apply CQRS in two ways:

  • Dividing requests into commands and queries.
  • Applying the CQRS concept to a higher level, leading to a distributed system.

We stick with the first one here and tackle the second definition in Chapter 16, Introduction to Microservices Architecture.

Goal

The goal is to divide all requests into two categories: commands and queries.

  • A command mutates the state of an application. For example, creating, updating, and deleting an entity are commands. In theory, commands do not return a value. In practice, they often do.
  • A query reads the state of the application but never changes it. For example, reading an order, reading your order history, and retrieving your user profile are all queries.

Dividing operations into mutator requests (write/command) and accessor requests (read/query) creates a clear separation of...