About the Author
Bing Liu

Bing Liu

Bing Liu is a certified Kansas City Sr. Java Developer with 18 years of experience in all phases of the Software Development Life Cycle. Bing has lead projects and worked in agile development environments using Java EE, Spring Framework, Spring MVC, Hibernate, JPA, SQL, Mockito Unit Testing, MQ Series, JavaScript, AngularJS, HTML, and CSS. She has extensive experience mentoring other developers, helping with system design, and performing code reviews to ensure implementation matches system specifications.

Centralizing Configurations with Spring Cloud Config

Bing Liu Microservices, Spring Boot, Technology Snapshot Leave a Comment

When the Microservices approach became popular a few years ago, many companies rushed to build their own microservices or to convert their legacy applications into microservices. Over the years, companies have implemented an abundance of microservices, mostly with Spring Boot. Each of them manage their own configurations across deployment environments like Dev, Test, and Prod.

Due to the nature of a complex business process, there are many common configurations (e.g. databases, queues, email servers, and FTP servers, etc.) used in the distributed services. This can result in services having redundant and confusing configs on a distributed system. It can become challenging to update the configs for too many services on a distributed system across multiple environments.

Thankfully, Spring Cloud Config provides the implementation to successfully resolve these issues. It provides server-side and client-side support for externalized configuration in a distributed system. With the Config Server, you have a central place to manage external properties for applications across all environments. The concepts on both client and server map identically to the Spring Environment and PropertySource abstractions, so they fit very well with Spring applications.

In this post, I’ll demonstrate Config Server and Client with example code. I’ll show you how to use Git or a local repository as a central place to store all the config files. The diagram below illustrates how the distributed client services (e.g. Investment Position/Price/Reporting Data service) fetch their configuration from the Config Server, which in turn retrieves them from one central place.

Interactive REST API Documentation with Swagger UI

Bing Liu Microservices, Spring, Spring Boot, Technology Snapshot 2 Comments

I am assisting a client that is migrating from a monolithic legacy application to a modern Microservice stack with Spring REST. We are helping to implement Swagger UI to provide both a front-end API UI, as well as to provide a level of documentation at the same time. This implementation has simultaneously met our project requirements, as well as garnering some positive feedback from our client!

Swagger UI is one of the most popular tools to visually render beautiful, interactive API documentation. In this blog, I’ll use a REST API application to demonstrate some usage of Swagger UI. The source project is available at https://github.com/bingliu2016/spring-boot-rest-swagger2.