My IOT Weather Station build with:
- ESP32 micro controller (NodeMCU-32S dev-kit, 2-core),
- OLED SSD1306 display,
- BME280 sensor (temperature, humidity, pressure).
- 2 separate threads with
_threadto use 2-cores:- 1st for data collecting and displaying on OLED screen (every 5 seconds),
- 2nd for
Web Server with socketssending to API (every 15 minutes).- Web Server commented to save memory and fix the Error 16 (device or resource busy)
- sending to API blocked main code (sensors & oled) for a while so moved to 2nd thread
- Build in blue LED turns on while sending to API
- Sends to API average sensor values for last 15 minutes (but maybe sending last values will be better for performance and memory?)
- Build-in button turns off displaying data on the OLED (to don't burn-in the screen)
- we don't power off the OLED to still display errors (but maybe should change it for energy efficiency when running on battery?)
- Error counters to soft restart a device (on 5th error) or exit while loop on 10th
- on any error or infinite loop I couldn't send files to fix the bug and have to erase an old flash and flash with MicroPython again (maybe there is a better way?)
- REST API to save data from ESP32 in database:
- Firestore DB because it's in GCN's free tier and I wanted to learn it
- SQL querying will be more suitable for this so maybe I will refactor it in the future
- basic POST security with secret in ENV variable
- basic endpoints to get data by place (office, home, etc.) and with limit
- Served from Docker container with Google Cloud Run
- Continuos Deployment with GitHub repo mirroring to Cloud Source and Google Cloud Build
- More endpoints to filter data, make statistics (by hour of day, day of week, periods), prepare them for charts and analysis.
- React App to display data with filters and charts to analyze trends (by day of week, by hour of day etc).
- Web sockets to update chart live? PWA for offline capabilities?