IOT temperature monitor
If you head over to https://github.com/supermitsuba/TemperatureMonitor you will see a temperature monitor system. My daughter’s room was getting cold, so my engineer brain kicked in. I had raspberry pi’s laying around, so that was no problem. Then I headed over to adafruit to pick up a temperature sensor. I had a wifi adapter, and a couple of wires, so I was all set to build this out.
I created a mysql database to house the data. Any database would do. I used docker so that it would allow me to deploy super easy. Within minutes I had a full working database. Next, I needed an API to dump data into the database, that’s where node.js comes in. Not only did I use node, but I used Typescript on top of that. Typescript gives static typing to javascript, which is useful for catching spelling and casing bugs.
On the client side, I created a node script and a c executable. The c executable uses wiring PI to poll the temperature. The node script calls the c executable and posts the data to the database. The reason I did this in node is that it is easier to call a web api in node than c. The only issue I ran into was that node would receive the data in a large chunk, instead of as the readings come in. This is ok, cause I can get the average of each chunk and that will save me space in the database. I dont need the readings down the the second, just something to see over time.
So, after that, here are the images:
For the web site, I used twitter bootstrap and chart.js. This gives it a decent way to view the graphs, even on a mobile device.