In the last part, I have briefly introduced the concept of contract testing and why we need it. This article will look into how we can use the Spring Cloud Contract to enforce contract testing between Spring-boot microservice apps. If you want to quickly dive into the code, feel free…

This is the first part of the series about contract testing for Spring-boot microservices apps. Part 1: Introduction to Contract Testing Part 2: Spring Cloud Contract Testing framework Part 3: Contract Testing with Pact Part 4: Contract Testing for GraphQl What is contract testing? Contract testing is a set of…

This article discusses few best practices that we have used with our RabbitMq cluster hosted with GCP's Kubernetes application. Note that every configuration comes with a certain trade-off. It might work for us but not necessarily for your different requirement and workload. Set lazy mode for queues With this mode…

Error handling is a very important part of a reliable and user-friend API. If you think of your API as a product, when something goes wrong with the product, it should clearly indicate the error to users and the reason why. …

In a world of monolithic architecture, it's very common that backend application does not just receive and respond to API request, but also perform scheduling job such as data cleaning, notification sending… In addition, the same app can also take the job from the queue and execute it. This architecture…

Distributed job queue is a very popular pattern to process heavy batch work, which can require much 'bigger' (read: expensive) hardware resource to complete. Let's illustrate with an example. Your system needs to send a newsletter to all of your users (e.g 100k users) on weekly basis. Since it is…

Recently, I ran into a situation where I wanted to customize the Json serialization of a list in an API response. TL/DR: you can find the full source code on my github: https://github.com/alexthered/spring-jackson-custom-list-serializer Concretely, I have a list of language strings: public class LanguageString { Locale locale; String value; } …

Recently, I have read an article of a Western expat living in my hometown Hanoi where he claimed that he is living a little life. That term rang a bell for me, probably I am living a similarly little life here far way from Vietnam. So what is a little…

Probably people do not go to gym to contemplate. Neither do I, I go to gym to work out, get myself recharged and wake my muscle up after hours of sitting rather static in front of the computer. But that does not stop me from thinking and observing. There is…