I have my library for reading sensor. It is open source and its name is OpenSensor. I think that it's useful for every body.
Besides, I have my a monitoring system in real time using Arduino, MQ2, MQ135, MG811, GP2Y10 sensors and shield wifi ESP8266. It use OpenSensor library to read value from sensor and push it to database of WebServer by ESP826.
This is link: https://github.com/tantt2810
Hoping it helpful for all,