Book Image

Hands-On Microservices with Kotlin

By : Juan Antonio Medina Iglesias
Book Image

Hands-On Microservices with Kotlin

By: Juan Antonio Medina Iglesias

Overview of this book

With Google's inclusion of first-class support for Kotlin in their Android ecosystem, Kotlin's future as a mainstream language is assured. Microservices help design scalable, easy-to-maintain web applications; Kotlin allows us to take advantage of modern idioms to simplify our development and create high-quality services. With 100% interoperability with the JVM, Kotlin makes working with existing Java code easier. Well-known Java systems such as Spring, Jackson, and Reactor have included Kotlin modules to exploit its language features. This book guides the reader in designing and implementing services, and producing production-ready, testable, lean code that's shorter and simpler than a traditional Java implementation. Reap the benefits of using the reactive paradigm and take advantage of non-blocking techniques to take your services to the next level in terms of industry standards. You will consume NoSQL databases reactively to allow you to create high-throughput microservices. Create cloud-native microservices that can run on a wide range of cloud providers, and monitor them. You will create Docker containers for your microservices and scale them. Finally, you will deploy your microservices in OpenShift Online.
Table of Contents (14 chapters)

Controlling services

Now that we have our personal cloud running with a microservice as a service, we need to learn how to control it. First, we will look at how we can scale these instances, then at how we can access the logs, and finally, how we can control these instances independently.

Scaling instances

Let's first look at which services we have to run with the following command:

docker service ls

This should show us our service instances:

ID            NAME           MODE        REPLICAS  IMAGE                        PORTS
syqgugo598xn hello-service replicated 1/1 localhost:5000/hello:latest *:8080->8080/tcp
os5j0iw1p4q1 registry replicated 1/1 registry:latest *:5000->5000...