development

Testing OpenTelemetry JVM instrumentation with Kotlin

Jun 29, 2021 OpenTelemetry observability Kotlin testing

The OpenTelemetry Java instrumentation agent automatically instruments many common frameworks but there are times you may want to customize your application's telemetry by adding your own custom spans, adding attributes to existing spans, etc. In that case, it can be helpful to verify the custom instrumentation through …

First steps into observability with OpenTelemetry, Honeycomb, and Kotlin

Jun 6, 2021 OpenTelemetry Honeycomb observability Kotlin

In this post we'll go through my initial journey to add observability to the Projektor test reporting app using OpenTelemetry and Honeycomb. Projektor already has traditional monitoring with metrics around p95 response times for each REST endpoint, counters for successful and failed operations, etc. But I was intrigued …

Verifying order of React elements with React Testing Library

Apr 6, 2021 React testing

Recently I was working on sorting rows in a table in React and I wanted to be able to verify the rows sorted into the correct order. The table shows flaky tests (that is, tests that intermittently fail) and is built with Material Table. Material Table conveniently supports sorting out of the box by clicking on the …

Customizing Recharts graphs for React and testing them with Cypress

Mar 14, 2021 React Recharts testing Cypress

After I added the ability to collect and store code coverage stats in the Projektor test reporting tool, I wanted to also add a graph that showed the trend of code coverage over time. Then users could track their repo's code coverage to see if was increasing, decreasing, or staying the same. The Projektor UI is built …

Using the GitHub API with Kotlin

Mar 10, 2021 github Kotlin

Recently as part of Projektor test report project, I wanted to add the capability to comment directly on pull requests with links to the test report, code coverage stats, etc. That way users could get easier and faster access to the information than searching through the CI output to find the link to the Projektor test …

Improving Postgres query performance with explain/analyze

Mar 7, 2021 performance database Postgres

Database queries slower than you'd like? With Postgres' built-in explain/analyze capability you can identify what's making the query slow and fix it. In this example, we'll analyze the performance of query called as part of an API GET endpoint. First, we'll seed our test database with enough data to get meaningful …

Integrating database access and management with Flyway and jOOQ into a Kotlin Ktor app

Feb 28, 2021 Kotlin Ktor jOOQ database Gradle Docker Postgres

One of my goals when I started a learning project a couple of years ago was to get more hands-on experience with Kotlin co-routines, so I explored app frameworks that natively supported co-routines. I landed on Ktor, an open-source framework from JetBrains (creators of Kotlin) that supports co-routines throughout the …

Individually release different artifacts from monorepo with GitHub Actions using tags

Feb 24, 2021 CI github github actions

For the Projektor open-source test reporting project I wanted to keep all the code in a single mono repo to make it easy to work on and manage. But over time as the project evolved it grew into multiple deployable artifacts, and I wanted to be able to release each of those components independently as needed: Server …

Kotlin test assertions with informative failure messages using Strikt

Feb 21, 2021 kotlin testing

When I started writing Kotlin code a couple of years ago, one of the main things I missed after previously writing tests with Groovy/Spock were the easy yet powerful assertions with Groovy's power assert - not to mention the expressive failure messages when a test failed. Groovy's power assert prints out the …