Jenkins failure light using particle photon

We use Jenkins at our current project at 99X Technology as the continuous integration server. We also have a separate Jenkins instance running on a separate server which execute periodical batch processing jobs against the production data.

When a Jenkins job fails, Jenkins would send an automated email to dev email group. In practice those email notifications easily stay in developers mailboxes without getting noticed. Sometimes things remain failing for a big part of the day, specially not-so-actively developed products and batch processing jobs. So I wanted a way to let the team quickly recognize when something goes wrong.

Couple of years ago, one of my colleague built a similar Jenkins light. Then it was lots of electronic related work to get it up and running. The integration with Jenkins server was done using a Jenkins notification application called Hudson tray application. We faced many integration issues there, which caused Jenkins light to be not-so-stable.

Having IOT devices so common these days, we found a handy little wifi-enabled board (photon) from particle.io as a handy solution to wire into LEDs. One of big advantages of particle is that they provide a free API you can use to easily send a message to your photon without having to configure any infrastructure yourself. So all what we needed to do was to expose an API function from photon and to make an HTTP request from Jenkins to our api.particle.io endpoint with the desired state of the lights (green vs red).

Getting started with photon device was really easy. I just claimed my device through https://setup.particle.io/ and configured wifi settings, and the device was up-and-running within few seconds!

I am no expert on developing electronic circuits. So I started with blink an LED hello world app. Soon I realized it was the ideal point to start building Jenkins light. Particle’s web IDE https://build.particle.io/build is a handy dev environment and loading code into my photon device is super easy.

We used two LEDs connected to different pins of the photon device to build the pilot Jenkins lights using LEDs. I exposed a function from my device code to api.particle.io and then got Jenkins post build task plugin to send an HTTP request to particle api via a windows shell script. The shell script use CURL command line tool to check all Jenkins jobs if any is failed.

Have a look at the particle code and windows script we used https://gist.github.com/isurusndr/88b4b5ae6367fe73464523894183abc1

Here is the final result with two LEDs plugged into the photon board as a pilot project. It is just USB powered and really easily to move around. We’ve been testing our pilot Jenkins lights for few days now and I am really happy how quickly we were able to notice failures in Jenkins.

Since then we improved our pilot Jenkins light, adding LED matrix panels for better visibility. We also extended it to have two set of lights on the same photon; one for Jenkins doing CI and one for Jenkins handling batch processing of data.