Learn Microservices with Spring Boot 3 - Chapter 7

This repository contains the source code of the practical use case described in the book Learn Microservices with Spring Boot 3 (3rd Edition). The book follows a pragmatic approach to building a Microservice Architecture. You start with a small monolith and examine the pros and cons that come with a move to microservices.

Chapter 7 version

In Chapter 7, you learn how to achieve loose coupling with an Event-Driven Architecture using a RabbitMQ message broker. Besides, you go through the extra advantages like the ability to implement different messaging patterns, load balancing, and resilience.

The main concepts included in this chapter are:

• Event-Driven Architectures: Pros and Cons
• Embracing Eventual Consistency, all the way up to the UI
• RabbitMQ main concepts, messaging patterns, and practical implementation
• Refactoring the microservices towards an Event-Driven strategy
• Resilience with persistent messages

As usual, the book uses this practical implementation to teach you why introducing a message broker between our microservices is a good idea. You learn the patterns before the tools, so you can use your knowledge to build similar architectures using a different technology stack - e.g. Kafka.

Running the app

Requirements:

• JDK 17
• Node.js v18.16.0
• npm 9.7.1
• RabbitMQ 3.12.2

1. You need a RabbitMQ server running. Run the server according to the instructions for your OS, for example:

   $ rabbitmq-server

2. To start the Multiplication microservice, you can use the command line with the included Maven wrapper:

   multiplication$ ./mvnw spring-boot:run

3. To start the Gamification microservice, you do the same from its corresponding folder:

   gamification ./mvnw spring-boot:run

4. The React application can be started with npm. First, you need to download the dependencies with:

   challenges-frontend$ npm install

5. Then, you start the server with:

   challenges-frontend$ npm start

Once the backend and the fronted are started, you can navigate to http://localhost:3000 in your browser and start resolving multiplication challenges. This time, you'll see the Leaderboard.

Questions

• Do you have questions about how to make this application work?
• Did you get the book and have questions about any concept explained within this chapter?
• Have you found issues using updated dependencies?

Don't hesitate to create an issue in this repository and post your question/problem there.

Purchase

You can buy the book online from these stores:

• Apress
• Amazon and other online stores.