On April 8th I stopped redirecting calgary.bike to Bike Calgary to start showing off the aggregated data that I was pulling together from the 3 Eco-Counter installations. With the source on GitHub, I thought it’d be worth explaining a little of the why and how.
At the start of January, the City of Calgary made public the web page for bike counter on the Peace Bridge with promises of making more available including at least 10 more during the upcoming cycle track pilot. The Peace Bridge counter had data stretching back to April 24th, 2014 and by default was always showing the entire daily data set.
My first curiousity was whether I can could have a bookmark to just show the last week or so worth of numbers which led me to figuring out how the webapp worked. (Good ol’ WebKit developer tools)
After that in tandem with some projects I was looking into for work I decided to start seeing about scrapping the data and storing it somewhere to compare numbers (different installations, averages, weather) more easily. So a big thank you for the people at the City and Eco-Counter for not telling me to “get lost and don’t use things inappropriately”.
As for how - the Python scripts just ask Environment Canada and the counters once a day for their last day’s worth of new data (if possible) and store it in Graphite. Interacting with the data is Grafana 2 behind nginx. All hosted on a tiny instance on some publicly available free compute resources that I just happen to also manage as part of my day job. Funnily, most of the script writing was done during an all nighter at a Denny’s in Kamloops waiting for 4 AM to roll around so I could swap some power cables in a maintenance window.
It’s nothing fancy but it’s fun to see what might come of it when data is made available.
1 - I had registered the domain last year and figured that was a good place to point until I had a better idea of how to use it.