Early in December, the Cambridge UK office held a late afternoon and evening Hackathon around the Apama Community Edition. With an office full of Raspberry Pi enthusiasts, it was perhaps no surprise that most of the projects revolved around the ARM build of Apama! Oh, and the pizza was good too.
Callum, Ian and Ben investigated upgrading our old GPIOPlugin to use the new (and much fancier) EPL Plugins API, which happily was a great success with all our old tests passing. Our next goal is a set of automated tests leveraging WiringPi’s ‘gpio’ tool to simulate signals, rather than constructing small boards and testing literally by hand. There are plenty more features yet to be added, so please visit the GitHub repo if you would like to contribute!
Scott also worked on porting his existing plugin for the Blinkt! LED bar to the new EPL plugin API. This turned out to be far easier than anticipated thanks to the excellent documentation for migrating plugins from the old API and the new version worked first time with all tests passing. The Blinkt! plugin effectively contains an implementation of the SPI protocol built directly on the WiringPi library, so a future project is likely to involve making this code more generally available through the generic Apama GPIO plugin.
Chris had a Banana Pi (a variant of a Raspberry Pi) connected to a USB-DMX interface to an RGBW LED PARcan. Using a connectivity transport interfacing with an OLA daemon that bridges to the USB-DMX interface, events could be used to set the intensity of RGBW LEDs. Unfortunately, the OLA daemon seemed to limit this to only 1-2 changes per second, so smooth fades were not possible; next step would be to talk to the USB-DMX adapter directly.
Kev and his 13yr old son Josh had built a PiHut LED Christmas tree, and got it running under Python, and then were looking at doing the same with the GPIO Plugin. Not that we’re starting the long-term future recruiting process early or anything…
All in all, the event was a lot of fun and something quite different from our normal work. We hope you enjoyed this window into the team, and perhaps feel inspired to join us in the Community!
The Apama Community Team