Recording Log Appender for Java Unit Testing
A short post about a simple Java Utility class to help out in Unit Testing the proper functioning of log statements in code under test.
WiFi Temperature Sensor
Building a WiFi temperature sensor, and showing the data as graph. Using DS18B20, WeMos D1 mini ESP8266, InfluxDb, Telegraf, Grafana.
Send new created Jira ticket info to MS-Teams Channels
Summary We are using (self hosted) Jira (the Atlassian Issue Tracker / Scrum / Kanban Board) at the office. And we wanted to receive a chat notification for each newly created ticket, to be received in Microsoft Teams Channels. Teams is a collaboration messenger tool like Slack or RocketChat. Jira can send new ticket/story creations using a web-hook to external tools. The web-hook sends a Jira specific JSON payload, no configuration options possible. The project you are looking at, consists…
P1 Energy Meter Reader using Python in Docker
A python script, running in a docker container, to read energy consumption and back delivery data from the digital “smart?” meter (as is installed in many homes in the Netherlands). Storing it in mysql for further use.
3D Printed Lamp Covers
My last electronics project was creating a LED dimmer for some dinner table lights. This all works fine, but the bare light bulbs were a bit bright to look at directly. The MVP (Minimal Viable Product) version to fix this problem consisted of some ugly paper strips, taped to the bulbs 😉 Even though this MVP version did help, it doesn’t look too good, so a long-term-solution was needed. The lamp fittings are metal, and have some ribs which make…
WiFi 240V AC Led Dimmer – Speech Controlled
I wanted to build my own WiFi dimmer, to connect my dinner table lights to Alexa (Amazon Echo Dot). The used parts are an ESP8266 (I used a Wemos D1 Mini Clone), an ATTiny45, some sort of power module to supply 3.3 volt, and a zero-cross-detector / Triac dimmer module.
Micro-services Architecture with Oauth2 and JWT – Part 3 – IDP
For migrating from legacy monolith (web) applications to something more modern and manageable, we have been switching to micro-services. Part 3 of a 5 part blog post shows the Identity Provider component.
Fluent Bit Elastic Search Data Type Filter
Summary I have created a Fluent Bit LUA Filter to force proper data types to be send to our Elastic Search (log collector) Database, to prevent Elastic from rejecting the log records. GitHub Project: https://github.com/atkaper/fluent-bit-lua-filter-elastic-data-types Environment We are running a bunch of (on premise) Kubernetes clusters, all having around 20 nodes, with many deployments on it. The deployments use different technologies; Java, Kotlin, Node.js, GO, Python, C, … and quite some standard open source applications. Most of them have been…
Micro-services Architecture with Oauth2 and JWT – Part 2 – Gateway
For migrating from legacy monolith (web) applications to something more modern and manageable, we have been switching to micro-services. Part 2 of a 5 part blog post shows the gateway component.
K8S Tiller/Helm History Cleanup
GitHub Project: https://github.com/atkaper/k8s-tiller-history-cleanup Introduction In our on premise Kubernetes cluster, we use Helm for a big part of our application / micro-services deployments. Helm uses an engine called Tiller (which is a deployment in the cluster). It executes the installs / updates / deletes, and it stores the results of deployments in the system as config maps. While migrating our applications to a new K8S cluster, we saw that we forgot to set a limit on the history which is…