Spring Boot Microservice Skeleton

This is a skeleton for a Spring Boot microservice. It is intended to be used as a starting point for new microservices.

Pre-requisites

• Java 17
• Spring Boot 3.x
• Gradle 8.x
• Docker

Features

• Reactive Web (WebFlux)
• OpenAPI 3.x documentation & Swagger UI
• Health check endpoint
• Logback logging
• Dockerized (multi-stage build)
• Checkstyle
• OWASP Dependency Check

Dependencies

Getting Started

Initial Project Configuration Changes

1. Clone this repository
2. Rename the project to your project name
3. Rename rootProject.name in settings.gradle.kts to your project name

Docker Configuration Changes

1. Update Dokerfile to use the correct jar file name ENTRYPOINT ["java", "-jar", "/app/demo-0.0.1SNAPSHOT.jar"].
2. Update Dockerfile Gradle tag to the latest version here.
3. Update Dockerfile Java tag to the latest version here.

Profiles

• default: This is the default profile that contains settings applicable to all environments. It serves as a baseline configuration for your application.

• dev: The dev profile is typically used for development environments. It may contain configurations specific to development, such as a local database setup, debugging options, and other settings that make development easier.

• test: The test profile is usually used for automated testing environments, like unit tests and integration tests. It can have configurations for in-memory databases or test-specific configurations that differ from the production setup.

• prod: The prod profile is meant for production environments. It contains configurations optimized for performance, security, and reliability. This is where your application runs in a real-world scenario.

JaCoCo

Adding exclusions through build.gradle:

tasks.jacocoTestReport {
	dependsOn(tasks.test)
	...
	afterEvaluate {
		classDirectories.setFrom(files(classDirectories.files.collect {
			fileTree(dir: it, exclude: [
				'**/SkeletonApplication.class',
			])
		}))
	}
}

Documentation

Api Docs

http://localhost:8081/api-docs

Swagger-ui

http://localhost:8081/swagger-ui

Metrics

Health Check

http://localhost:8081/health

Metrics

http://localhost:8081/metrics

Logging

http://localhost:8081/loggers

Best Practices

Design

Basic-Required

• Backend for Frontend (BFF) as an API Gateway
• Database schema per service
• Expose the /health endpoint

Medium

• Injection of external configuration at runtime
• Service Contracts Testing Agreement

Advanced

• Liquibase for database change management
• Dapr for event-driven programming
• Implement Distributed Tracing
• If High Performance is Required, Spring Native
• Early and Frequent DevSecOps

Programming

Basic-Required

• Development tools
• Project structure
• Logging rules
• Startup Profiles Configuration
• Code documentation with Open API
• Use of UI Swagger
• Input validation in controllers
• Use of Lombok
• Use of Checkstyle

Medium

• Project dependency standards
• Simple and clean controller layer
• Service layer focused on business logic
• Constructor injection instead of @Autowired
• Pagination and sorting with Spring Data JPA
• Unit testing with JUnit and Mockito

Advanced

• JSON log configuration with Logback
• Global exception handling
• Avoid unnecessary additional dependencies
• Review Dependency Updates
• Use of Maven Wrapper