The Problem
The City of Calgary has a number of resources available for finding out what development is happening in your community. The primary resource is the Development Map, which while comprehensive is significantly off putting because of the amount of information presented. It also only covers the major developments - land use changes and development permits, that are open to some community consultation.
My particular community - Sunalta - has an additional problem because we joined a project with the City of Calgary removing the need for most businesses to apply for a development permit for change of use on our Main Streets (10th Ave. and 14th St). While we are very supportive of the project, we’ve always struggled with notification or knowing when a new business has moved in so we could welcome them to the community. The lack of development permit makes this a bit harder.
The Data
Thankfully, the City provides this data via their open data portal:
However the City also releases the information for more minor information to help answer resident’s questions that are sometimes directed to us.
- [Building Permits])(https://data.calgary.ca/Business-and-Economic-Activity/Building-Permits/c2es-76ed)
- Tenancy Changes - when businesses move in to the neighbourhood!
But can I use it?
So cool, we have some data. How do we make this easier to use? The Open Data Portal does present the data and even allows you to do some visualization but you’re unable to share your visualizations and filtered datasets without logging in. So using data.calgary.ca is only good for exploration. It also does not provide a great way for less technically minded folks on our board to get this data or even glance at it.
So the next best thing is to look at setting something up to read the data and create the visualizations we want!
The “solution”
From here I’ll share my notes about how I arrived at my solution. It’s far from the only solution, but is the result of my trial, error, and realizing there are a LOT of options I’m simply not even aware of.
Filtering
The first step was to try and filter the data from the 4 datasets to just the area I cared about - turns out this is easy with Socrata’s Query Language. Adding ?communityname=SUNALTA to my queries and the python py-soda library and I’m off to the races. The land use dataset however does NOT include community fields, so I bet heavily on that 1000 land use items is sufficient for the last 365 days worth of data.
Visualization (Streamlit)
The next tech I dove into - was how can I show off this data on a map and in a table. At work another team has started using Streamlit and it was incredibly easy to get started with. It also had a fantastic feature where it will cache data removing my worry about needing to jump through hoops to avoid hitting data.calgary.ca too many times and needing to create a caching layer myself.
The biggest gotchas with streamlit I have found is that the default map is nowhere near as featureful as using the plotly library to put dots on the map. Plotly’s table feature while supported has terrible performance and causes everything to drag to a halt. As such I went with Plotly for showing the map, but used Streamlit’s native table view to show off the data.
Hosting
While Streamlit is easy to run and put a reverse proxy in front of (for SSL and caching), they do also run a free service to deploy your Streamlit app to Heroku for showing off. Streamlit Sharing is free for public repositories (like this project). It will also hook up to GitHub to redeploy your app whenever you push an update without needing to code this in GitHub workflows yourself. Very convenient.