Simple NodeJS server and SQLite3 logger for the DS18B20 digital temperature sensor on the Raspberry Pi.
A NodeJS server for the DS18B20 GPIO temperature sensor on the Raspberry Pi. The sensor is accessed using the w1-gpio and w1-therm kernel modules in the Raspbian distro. The server parses data from the sensor and returns the temperature and a Unix time-stamp in JSON format, this is then written to an SQLite database on the Pi. A simple front-end is included and served using node-static, which performs ajax calls to the server/database and plots temperature in real time or from a time-series, using the highcharts JavaScript library.
Server supports multiple remote and one local sensor. Sensors configuration: id, name and accuracy are stored in database. Remote sensor readings are added with http GET call, e.g. http://localhost:8000/addtemp?sensorid=1&temp=12
- load_gpio.sh - bash commands to load kernel modules
- server.js - NodeJS server, returns temperature as JSON, logs to database and serves other static files
- temperature_plot.htm - example client front-end showing live temperatures from local sensor (no remote sensors support yet)
- temperature_log.htm - example client front-end showing time-series from database records
- build_database.sh - shell script to create database schema (also one local and two remote sensors are added)
- build_example_database.sh - schell script to create example database with real world data from the Pi recorded in UK Jan-Feb 2013
- NodeJS
- SQLite3
- node-sqlte3 module
- Run "load_gpio.sh" script as root to load kernel modules for the sensor
- Run the "build_database.sh" script to create "piTemps.db". Note this wil drop any existing database of the same name in the directory
- Open "server.js" and edit line 35 to read the serial number of your sensor in /sys/bus.
- In a terminal run "node server.js" to start the server.
- Open a web browser on the Pi and go to http://localhost:8000/temperature_plot.htm to see a plot of current temperature. Go to http://localhost:8000/temperature_log.htm to see a plot of logged temperature.
http://www.cl.cam.ac.uk/freshers/raspberrypi/tutorials/temperature/
