Skip to main content

kotlin

2020


Running Testcontainers On Dynamic Ports

Running integration tests locally with Docker can be challenging when fixed ports are unavailable due to conflicts. This issue is compounded in shared CI environments where multiple workers are in use. However, using testcontainers can help overcome these obstacles by enabling the startup of Docker containers that listen on random ports.

Kotlin Playground Shortcode for Hugo

Kotlin Playground is HTML component which creates Kotlin-aware editors capable of running code from HTML block elements. Here I explain how to embed runnable Kotlin code block in your Hugo-powered blog.

2019


Building Data Pipeline with Kotlin Coroutines Actors

In this post I will show how to build simple data-enriching pipeline using Kotlin coroutines. I will use Channels and Actors abstractions provided by kotlinx-coroutines. In Actors model “actors” are the universal primitives of concurrent computation. In response to a message that it receives, an actor can: make local decisions, create more actors, send more messages, and determine how to respond to the next message received. Actors may modify their own private state, but can only affect each other through messages (avoiding the need for any locks).

2018


Customizing REST API Error Response in Spring Boot / Spring-Security-OAuth2

Defining error format is important part of REST API design.

Spring-Boot and Spring Security provide pretty nice error handling for RESTful APIs out of the box. Although it has to be documented, especially when contract-first approach to API design is used.

It is good idea to follow some common format for error responses. But OAuth2 specification and Spring Boot format may not satisfy those requirements.