Microservices is a software architecture strategy that has been in use for some years, with the goal of making services more scalable. Monolithic applications are losing ground to service-oriented projects, owing to the need for today's businesses to grow rapidly and dynamically. By designing this new architectural model, object-oriented principles, standards, decoupling, and responsibilities have become fundamental beyond automated testing.
Knowledge of microservices will enable you to create maintainable and scalable applications. By the end of this book, you will be fully capable of creating interoperable microservices, testable and prepared for a great performance.
This book is intended for readers who have experience with web development but want to improve their development techniques to create more maintainable and scalable applications. Readers are not expected to have development experience using microservices. The concepts and standards demonstrated in this book enable the reader to develop applications that are simple to understand and support a high volume of access.
Chapter 1, Understanding the Microservices Concepts, gives you an overview of microservice concepts. This chapter will help you to understand the concepts behind the architecture, for example, the client-first approach and domain definition.
Chapter 2, The Microservice Tools, takes you through the most common tools to be applied to microservices. Once you know your customers and how to define the domains of your application, it's time to make technical decisions—which programming language to use, which framework is appropriate, and how to validate whether your microservice template is functional or not.
Chapter 3, Internal Patterns, introduces you to internal microservice application patterns. We will address topics such as caching strategies, workers, queues, and asynchrony.
Chapter 4, Microservice Ecosystem, covers how to create a group of resilient and scalable microservices from a monolithic application. The chapter also focuses on how to separate microservices correctly in their respective containers and explains the distribution of the storage layer.
Chapter 5, Shared Data Microservice Design Pattern, covers a special case. Normally, microservices are totally independent in business, testing, communications, connections, and storage, but not in this pattern. The shared pattern is a special pattern for migration concepts, from monolithic to microservices; overall, it's a pattern for transitioning.
Chapter 6, Aggregator Microservice Design Pattern, covers the most simple and typical pattern, which basically consists of applying data orchestration to microservices.
Chapter 7, Proxy Microservice Design Pattern, covers the proxy pattern, which is very similar to the aggregator pattern. When thinking of the structure, it's used when it isn't necessary to join data to send it to the end user. Understanding the differences between the proxy pattern and the aggregator pattern, as well as the correct request redirection for the responsible microservice, is the goal of this chapter.
Chapter 8, Chained Microservice Design Pattern, covers the chained pattern, where the information that will be sent to the client can be consolidated into a chain. Explaining information consolidation is the main objective of this chapter.
Chapter 9, Branch Microservice Design Pattern, covers the branch pattern, which is a mix of the aggregator and chain patterns. It's normally used when, in the backend, a microservice doesn't have all the data to complete a task or should directly notify another microservice. This chapter explains when this pattern composition is useful and the ways in which it could be good for the business.
Chapter 10, Asynchronous Messaging Microservice, explains one of the most complex patterns: applying asynchronism at the microservice level. This chapter is about how microservices can communicate asynchronously using messaging tools.
Chapter 11, Microservices Working Together, is a conclusion on patterns. After learning all about the microservice patterns, we will see how to put all the microservices to work together.
Chapter 12, Testing Microservices, explains the most plausible possibilities for testing and how to make this part, which is so important, simple.
Chapter 13, Monitoring Security and Deployment, covers what is necessary and best practices to maintain microservices in production.
Having some knowledge of OOP and package structure in Go (golang) will make reading this book more interesting.
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