Book Image

Embracing Microservices Design

By : Ovais Mehboob Ahmed Khan, Nabil Siddiqui, Timothy Oleson
Book Image

Embracing Microservices Design

By: Ovais Mehboob Ahmed Khan, Nabil Siddiqui, Timothy Oleson

Overview of this book

Microservices have been widely adopted for designing distributed enterprise apps that are flexible, robust, and fine-grained into services that are independent of each other. There has been a paradigm shift where organizations are now either building new apps on microservices or transforming existing monolithic apps into microservices-based architecture. This book explores the importance of anti-patterns and the need to address flaws in them with alternative practices and patterns. You'll identify common mistakes caused by a lack of understanding when implementing microservices and cover topics such as organizational readiness to adopt microservices, domain-driven design, and resiliency and scalability of microservices. The book further demonstrates the anti-patterns involved in re-platforming brownfield apps and designing distributed data architecture. You’ll also focus on how to avoid communication and deployment pitfalls and understand cross-cutting concerns such as logging, monitoring, and security. Finally, you’ll explore testing pitfalls and establish a framework to address isolation, autonomy, and standardization. By the end of this book, you'll have understood critical mistakes to avoid while building microservices and the right practices to adopt early in the product life cycle to ensure the success of a microservices initiative.
Table of Contents (16 chapters)
1
Section 1: Overview of Microservices, Design, and Architecture Pitfalls
6
Section 2: Overview of Data Design Pitfalls, Communication, and Cross-Cutting Concerns
10
Section 3: Testing Pitfalls and Evaluating Microservices Architecture

Understanding the CQRS principle

In this section, we will learn about CQRS, the different types of CQRS, and why we might want to consider this pattern. CQRS was introduced by Greg Young in 2010. It is based on the command-query separation (CQS) principle that was introduced by Bertrand Meyer, in 1988. In this scenario, we separate the responsibilities of querying or retrieving data from commands, which results in a change in state or mutates our data. The CQRS principle takes the concept of CQS and builds on it, adding more details and capabilities such as having a separate database for reads and writes. This can add complexity but has provided some useful capabilities such as persisting events known as event sourcing. We can play these events back to give us a very detailed audit trail or history of the state of our data: when it changed, who changed it, and why.

Types of CQRS

As mentioned earlier, CQRS was built on the principles of CQS. Additionally, we mentioned CQRS has...