build-alert

Polls a jenkins build status page and switches on a relay for a given period of time if the build is broken.

One of the teams I worked in didn't have a direct way of getting alerts when the build broke. Email notifications are no use if people are just busy in their IDEs so we wanted something a little more conspicuous. I thought it would be fun to set up an industrial-type strobe light. I wanted a big, red strobe but at the time the only thing I could find that looked practical was a small but very bright blue mini-strobe.

Originally written in Python 2 in 2012 and tested on macOs and Ubuntu Linux.

Hardware

This uses the "PhidgetInterfaceKit". This board has big fat tracks on the switched side of the board and the relays are rated for more than 240 big man-volts of British Mains Electricity at 3 Amps. Far more than enough for my small, blue strobe light.

Tip

To run this You need to install the driver to get this working and this has changed on the mac: https://www.phidgets.com/docs/OS_-_macOS#Getting_started_with_macOS

• In the UK you can buy the hardware from Active Robots

Configuration

At the top of the file poller_with_kit.py there are three hard-coded variables:

• normal_poll_waiting_time This is the number of seconds between attempts to check the build server state.
• alert_for_seconds The number of seconds that the relay is switched on - i.e. the duration of the flashing strobe
• after_breakage_resume_polling_after_seconds We don't need to be continuously nagged until the build is fixed so we wait this number of seconds before we resume polling again.

Better Modern Ways to do it?

Today there are most likely better options.

I chose the Phidgets hardware because it was a ready-made solution and could in principle switch a mains powered lamp although I didn't need to do that. The blue strobe lamp shown in the picture is actually running on a 12V DC power adapter.

Some other ways you could easily do this:

• Set up a Raspberry PI / Beaglebone Black as a stand-alone "build alert server" and power a relay from the GPIO pins. You can even get a fairly inexpensive ready-made interface board to handle the relay such as the Featherwing one from Adafruit.
• Configure a Raspberry Pi Pico microcontroller with a custom MicroPython script that connects and polls over wi-fi. It could operate a relay or even simpler and cheaper maybe just a bunch of LEDs pointing in all directions.