Building Microservices with Micronaut®: A quick-start guide to building high-performance reactive microservices for Java developers

✍ Scribed by Nirmal Singh, Zack Dawood

• Publisher: Packt Publishing
• Year: 2021
• Tongue: English
• Leaves: 363
• Category: Library

✦ Synopsis

Explore different aspects of building modular microservices such as development, testing, maintenance, and deployment using the Micronaut framework

Key Features

• Learn how to build scalable, fast, and resilient microservices with this concise guide
• Explore the many advantages of using reflection-free, compile-time dependency injections and aspect-oriented programming
• Build cloud-native applications easily with the Micronaut framework

Book Description

The Micronaut® open source software is a JVM-based framework, designed to create microservices quickly and easily. This book will help full-stack and Java developers to build modular, high-performing, and reactive microservice-based apps using Micronaut.

You'll start by building microservices and learning about the core components of Micronaut, 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 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 the Micronaut framework, 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 Micronaut.

By the end of this book, you'll be able to build, test, deploy, and maintain your own microservice apps using Micronaut.

What you will learn

• Understand why Micronaut is best suited for building microservices
• Build web endpoints and services in the Micronaut framework
• Safeguard microservices using Session, JWT, and OAuth in Micronaut
• Get to grips with event-driven architecture in Micronaut
• Discover how to automate testing at various levels using built-in tools and testing frameworks
• Deploy your microservices to containers and cloud platforms
• Become well-versed with distributed logging, tracing, and monitoring in Micronaut
• Get hands-on with the IoT using Alexa and Micronaut

Who this book is for

This book is for developers who have been building microservices on traditional frameworks such as Spring Boot and are looking for a faster alternative. Intermediate-level knowledge of Java programming and implementing web services development in Java is required.

Table of Contents

1. Getting Started with Microservices Using the Micronaut Framework
2. Working on Data Access
3. Working on the RESTful Web Services
4. Securing the Microservices
5. Integrating Microservices using the Event-Driven Architecture
6. Testing the Microservices
7. Handling Microservice Concerns
8. Deploying Microservices
9. Distributed logging, tracing and monitoring
10. IoT with Micronaut
11. Building enterprise grade microservices

✦ Table of Contents

Cover
Title Page
Copyright and Credits
Contributors
Table of Contents
Preface
Section 1: Core Concepts and Basics
Chapter 1: Getting Started with Microservices Using the Micronaut Framework
Technical requirements
Introducing microservices and their evolution
Understanding microservices design patterns
Decomposition design patterns
Integration design patterns
Data management patterns
Cross-cutting patterns
Why Micronaut is the best choice for developing microservices
Getting started with the Micronaut framework
Installing the Micronaut CLI on mac OS
Installing the Micronaut CLI on Windows
Working on a hello world project in the Micronaut framework
Creating a hello world project using the Micronaut CLI
Creating a hello world project using Micronaut Launch
Summary
Questions
Section 2: Microservices Development
Chapter 2: Working on Data Access
Technical requirements
Integrating with persistence in the Micronaut framework
Integrating with a relational database using an ORM (Hibernate) framework
Generating the pet-owner schema in PostgreSQL
Creating a Micronaut application for the pet-owner microservice
Creating the entity classes
Defining relationships among entities
Creating data access repositories
Creating services for entities
Performing basic CRUD operations
Wrapping up
Integrating with a relational database using a persistence (MyBatis) framework
Generating the pet-clinic schema in PostgreSQL
Generating a Micronaut application for the pet-clinic microservice
Defining a MyBatis factory
Creating the entity classes
Defining the mappers (repositories) for the entities
Creating services for entities
Performing basic CRUD operations
Wrapping up
Integrating with a NoSQL database (MongoDB)
Creating a vet-reviews collection in MongoDB
Generating a Micronaut application for the pet-clinic-reviews microservice
Configuring MongoDB in Micronaut
Creating the entity class
Creating a data access repository
Creating a service for the entity
Performing basic CRUD operations
Wrapping up
Summary
Questions
Chapter 3: Working on RESTful Web Services
Technical requirements
Working on restful microservices in the Micronaut framework
Using DTOs for the endpoint payloads
Implementing DTOs
Using MapStruct to define mappers
Modifying the services to use DTOs
Creating the restful endpoints for a microservice
Creating an endpoint for retrieving a list of resources
Creating an endpoint for retrieving a specific resource
Creating an endpoint for inserting a resource
Creating an endpoint for updating a resource
Creating an endpoint for deleting a resource
Using Micronaut's HTTP server APIs
Binding HTTP requests in the Micronaut framework
Validating data
Handling errors
Versioning the APIs
Using Micronaut's HTTP client APIs
Performing an HTTP PUT operation
Performing an HTTP POST operation
Performing an HTTP PUT operation
Performing an HTTP DELETE operation
Summary
Questions
Chapter 4: Securing the Microservices
Technical requirements
Working on RESTful microservices in the Micronaut framework
The basics of Micronaut security
Securing service endpoints using session authentication
Implementing a basic authentication provider
Configuring authorizations for the service endpoints
Using JWT authentication to secure the service endpoints
Setting up Keycloak as the identity provider
Securing the pet-clinic microservice using token-based authentication
Using OAuth to secure service endpoints
Setting up Okta as the identity provider
Enabling SSL in the Micronaut framework
Securing the pet-clinic-reviews microservice using OAuth
Summary
Questions
Integrating Chapter 5: Microservices Using Event-Driven Architecture
Technical requirements
Understanding event-driven architecture
Event messaging or a pub/sub model in an event-driven architecture
Event streaming in event-driven architecture
Event streaming with the Apache Kafka ecosystem
Integrating microservices using event streaming
Setting up the Apache Kafka ecosystem locally
Implementing an event-producer client in the pet-clinic-reviews microservice
Implementing an event consumer client in the pet-clinic microservice
Summary
Questions
Section 3: Microservices Testing
Chapter 6: Testing Microservices
Technical requirements
Understanding the testing pyramid
Unit testing in the Micronaut framework
Unit testing using JUnit 5
Service testing in the Micronaut framework
Integration testing using Testcontainers
Setting up the Testcontainers in the Micronaut application
Writing integration tests using Testcontainers
Summary
Questions
Section 4: Microservices Deployment
Chapter 7: Handling Microservice Concerns
Technical requirements
Externalizing the application configuration
Using distributed configuration management to externalize the configuration
Documenting the service APIs
Using Swagger to document the pet-owner service endpoints
Implementing service discovery
Implementing service discovery using Consul
Implementing the API gateway
Implementing the API gateway service
Implementing the fault tolerance mechanisms
Leveraging built-in mechanisms
Summary
Questions
Chapter 8: Deploying Microservices
Technical requirements
Building the container artifacts
Containerizing the Micronaut microservices using Jib
Deploying the container artifacts
Using docker-compose to deploy the pet-clinic services
Summary
Questions
Section 5: Microservices Maintenance
Chapter 9: Distributed Logging, Tracing, and Monitoring
Technical requirements
Distributed logging in Micronaut microservices
Setting up ELK in Docker
Integrating Logstash with Micronaut microservices
Verifying the distributed logging in the pet-clinic application
Distributed tracing in Micronaut microservices
Implementing distributed tracing in Micronaut
Verifying the distributed tracing in the pet-clinic application
Distributed monitoring in Micronaut microservices
Setting up Prometheus and Grafana in Docker
Configuring microservices for distributed monitoring
Verifying the distributed monitoring in the pet-clinic application
Summary
Questions
Section 6: IoT with Micronaut and Closure
Chapter 10: IoT with Micronaut
Technical requirements
Basics of IoT
Working on the basics of Alexa skills
Basics of Alexa skills
Basics of intents
Your first HelloWorld Alexa skill
Testing your code
Integrating Micronaut with Alexa
Summary
Questions
Chapter 11: Building Enterprise-Grade Microservices
Technical requirements
Bringing it all together
Architecting enterprise microservices
Planning and analysis
Design
Develop
Deploy
Manage and maintain
Understanding Micronaut's OpenAPI
Scaling Micronaut
Implementing Micronaut's microservices
Summary
Questions
Assessment
Chapter 10
Chapter 11
Other Books You May Enjoy
Index