Today I Learned: Parsing JSON in Python with jq and mapping it with kepler.gl

I was intrigued by Simon Wilison's posts about screen scraping data using github, so I got right to work on it with respect to tracking the Rockmite's antenna performance, and WOW!

The map above was created using data from the new project so far.

Screen Scraping via the Network Tab of the Chrome Browser Developer Tools Tab

Using Simon's lightning talk, it was pretty easy to find the data I wanted from the RBN site.

Github Actions

Again pulling from Simon's talk, I was pretty quickly able to create a github action that runs a few times an hour to collect all the calls spotted from ham radio call signs that fit the pattern "KD0*". It took me a large-ish bit of time to debug whether or not the curl command or the jq command used to process the data were having issue. (It was the curl command. If your URL has arguments following a '?' you'll need to enclose it in double quotes.)

Now that I was pulling out the call data, the immediate next issue was actually doing something with the data to get it onto a map, and that brought me to

Using jq to format JSON data

jq can be used to format JSON data. It sounds a bit plain to say that, so let me expand. This Tool Is Incredibly Useful And I Didn't Know About It Before. (hehehehehe... and other maniacal spark laughter.)

I'm still learning on this front, but I've managed to dump out things like:

Which is pretty close to what I need.

The most useful web based tool I've found for playing with JSON and jq so far is https://jqplay.org.

Ultimatley the idea is to have jq dump out data that kepler.gl can consume which brings us to:

kepler.gl for animated mapping

Again, pulling from Simon's lightning talk, I found kepler.gl and the fact that it can make animated maps. I hand edited a few of the Rockmite's spots from yesterday to arrive at a file kepler.gl could read and animate, and arrive at:

There's refinements that need to be done, but So Much Cool Stuff!!!

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