Why all these software tools for publishing and managing the data. Why not just put the data in a csv file from a python script, then use gnuplot to plot it when requested from a web server running on the pi.
Reminds me of the recent hacker news post "is this madness ever going to end?" https://news.ycombinator.com/item?id=29898030
This is the world I want to live in, one in which I spend more time than is needed to craft a beautiful product (inside/code and outside/ui), where I don't have to sacrifice quality for time and accumulate tech debt so I can rush to market. I've accepted that I'll probably never have a professional job where quality is more important than speed, and where beauty is more important than scrum ceremony, so books and projects like this are where I satisfy the innate need for elegance, while also building something I've wanted for a long time (a very hackable and very open weather station).
Also without a doubt the skills learned here will make me a much better developer for the day job and side gigs (where I use Elixir/Phoenix quite a bit). If I use python and GNU plot, there's no deepening or broadening of the skillset and knowledge that I want to use.
This post is already pretty long but I wanted to add that the "stop the madness" post actually resonated with me a lot (even if I disagree with some of the conclusions). If you want the madness to stop, learning Elixir/Phoenix is actually a great way to do that. You can crank out simple solutions very easily. The JS world is finally coming back around to the idea that there's great value in SSR, and Phoenix makes that easy and a joy, and with LiveView you really can replace a lot of SPAs, especially those where realtime interactivity is needed (such as chat apps). There's still an important place for a SPA for PWAs and/or offline functionality, but so few applications have that anyway.
Nerves is an incredibly powerful tool. It will burn a firmware image to an SD card for you that you can just insert into your device and boot. It's almost like magic. There is also an elegant OTA (over-the-air) update process so that you can update your device remotely, where it deals with managing disk partitions so that the system can pull the new image and boot into it without the need to remove the SD card. You also get the benefits of lots of community work for supporting a big number of devices. And when what the community has created isn't working for you, it's all just open-source buildroot goodness so you can do your own thing. In a project I was working on I needed an external wifi adapter vs. the onboard one and was able to recompile a custom kernel to enable the right drivers. It was a lot easier than I ever imagined.
You also get Elixir - which is pretty rad in and of itself to have such a powerful runtime on a tiny little device.
So sure, you can do as you describe but you are only considering about 1% of this project: rendering data for the user to see. You are missing out on the fact that in order to gather that data you need to be able to communicate with some kind of embedded chip that is actually collecting those measurements, often via a very low-level communication protocol like i2c or spi. You need to parse the measurements, which are often not in a human-friendy format, then you need to get the data out/off the device so you need a network stack, your network might go down so you need a system to capture data and replay it once the network is restored, etc. It's really sophisticated! Seeing a book like this is incredible.
On a side note your website, https://woodgears.ca/, is awesome. If anyone sees this comment check out https://woodgears.ca/marbleadd/index.html
Why would you build a wooden machine with marbles, just to add numbers together?
Just use an excel spreadsheet, or a $1 calculator. When will this madness end?