Book Image

Building Microservices with Micronaut®

By : Nirmal Singh, Zack Dawood
Book Image

Building Microservices with Micronaut®

By: Nirmal Singh, Zack Dawood

Overview of this book

The open source Micronaut® framework is a JVM-based toolkit designed to create microservices quickly and easily. This book will help full-stack and Java developers build modular, high-performing, and reactive microservice-based apps using the Micronaut framework. You'll start by building microservices and learning about the core components, such as ahead-of-time compilation, reflection-less dependency injection, and reactive baked-in HTTP clients and servers. Next, you will work on a real-time microservice application and learn how to integrate Micronaut projects with different kinds of relational and non-relational databases. You'll also learn how to employ different security mechanisms to safeguard your microservices and integrate microservices using event-driven architecture in the Apache Kafka ecosystem. As you advance, you'll get to grips with automated testing and popular testing tools. The book will help you understand how you can easily handle microservice concerns in Micronaut projects, such as service discovery, API documentation, distributed configuration management, fallbacks, and circuit breakers. Finally, you'll explore the deployment and maintenance aspects of microservices and get up to speed with the Internet of Things (IoT) using the Framework. By the end of this book, you'll be able to build, test, deploy, and maintain your own microservice apps using the framework.
Table of Contents (20 chapters)
1
Section 1: Core Concepts and Basics
3
Section 2: Microservices Development
8
Section 3: Microservices Testing
10
Section 4: Microservices Deployment
13
Section 5: Microservices Maintenance
15
Section 6: IoT with Micronaut and Closure

Event streaming with the Apache Kafka ecosystem

Apache Kafka is an industry-leading event streaming system. In the Apache Kafka ecosystem, the following are some of the key components:

  • Event topic: An event topic consists of a stream of immutable, ordered messages belonging to a particular category. Each event topic may have one or more partitions. A partition is indexed storage that supports multi-concurrency in Apache. Apache Kafka keeps at least one partition per topic and may add more partitions as specified (at the time of topic creation) or required. When a new message is published to the topic, Apache Kafka decides which topic partition will be used to append the message. Each topic appends the most recent message at the end. This is shown in the following diagram:

Figure 5.3 – Apache Kafka topic anatomy

As shown in the preceding diagram, when a new message is published to the steam, it is appended at the end. Event consumers can...