Spring Cloud Config Basics

Overview

This sample shows off how one can use Spring Cloud Config Server can externalize configuration of each application. It also showcases ways that one can create configurations that target different environments and overriding configuration values based on application profiles.

Spring Boot 2.4 changed how bootstrap configuration works, the billboard app uses Spring Boot 2.4+ approach to configuration, and the greeter app uses the Spring Boot 2.3 approach by turning on legacy processing mode see

• Changes Spring Boot 2.4 introduced
• Config file processing in Spring Boot 2.4

Run the Demo

• Fork https://github.com/practical-microservices/spring-cloud-config-basics-repo.git into your own Git repo on GitHub
• Import the root of the repo into your favorite Java IDE
• Edit to config-server\src\main\resources\application.yml to point to your fork from step 1
• Run config-server application
• Run billboard application
• Run greeter application

Things to try out

• Access each application and check how the message is mapping to configuration value associated with every app. Examine the config repo to see how the mapping works. Notice that the name of the yml file matches the application name configured under spring.application.name
• Change the Spring profile of billboard application to dev and see how the message is affected - the new values is coming out of configuration file billboard-dev.yml
• Access the /health endpoint of each app. Notice how the configuration defined in application.yml applies to both applications.

Resources to Learn More:

• https://cloud.spring.io/spring-cloud-config/