Book Image

Microservice Patterns and Best Practices

By : Vinicius Feitosa Pacheco
Book Image

Microservice Patterns and Best Practices

By: Vinicius Feitosa Pacheco

Overview of this book

Microservices are a hot trend in the development world right now. Many enterprises have adopted this approach to achieve agility and the continuous delivery of applications to gain a competitive advantage. This book will take you through different design patterns at different stages of the microservice application development along with their best practices. Microservice Patterns and Best Practices starts with the learning of microservices key concepts and showing how to make the right choices while designing microservices. You will then move onto internal microservices application patterns, such as caching strategy, asynchronism, CQRS and event sourcing, circuit breaker, and bulkheads. As you progress, you'll learn the design patterns of microservices. The book will guide you on where to use the perfect design pattern at the application development stage and how to break monolithic application into microservices. You will also be taken through the best practices and patterns involved while testing, securing, and deploying your microservice application. At the end of the book, you will easily be able to create interoperable microservices, which are testable and prepared for optimum performance.
Table of Contents (20 chapters)
Title Page
Dedication
Packt Upsell
Contributors
Preface
Index

Applying CQRS and event sourcing


Currently, we have three microservices responsible for the provision of news in our application: famous_news_service, sports_news_service, and politics_news_service. Each have the same technical structure, but are separated by having different domains. As the domain of each of these microservices is set, it can receive completely different technical developments; however, in this case, we will modify the three, in the same way, to apply the aggregator design pattern. The first modification will be in the storage tier.

Separating the database

Inside of each microservice directory, we will create two more directories.In each of these new directories will be a Dockerfile with configurations for the database. We will use two different databases for each microservice to use CQRS.One database is for CommandStack and one for QueryStack.

With these changes, the directory structure for the News microservices looks like this:

├───FamousNewsService 
│   ├───command_db ...