A quick and dirty integration for Home Assistant to integrate PurpleAir air quality sensors. This will create an air_quality sensor with the relevant data and create an additional AQI sensor for ease-of-use.

Simply copy the /purpleair directory in to your config's custom_components directory (you may need to create it), restart Home Assistant, and add the integration via the UI (it's simple!).

To find a sensor to integrate:

1. Look at the PurpleAir Map.
2. Find and click an available outdoor station (indoor won't do you any good).
3. In the station pop up, click on "Get This Widget".
4. Right-click the "JSON" link at the bottom of the black box and copy the link. (Copy Link Location, et al.)
5. Go to Home Assistant and go to the Integrations Page.
6. Add the PurpleAir integration.
7. Paste the link and finish.

You'll have two entities added: an air_quality entity and a sensor entity. The air quality fills out all available values via the state dictionary, and the sensor entity is simply the calculated AQI value, for ease of use. (The AQI also shows up as an attribute on the air quality entity as well).

Sensor data on PurpleAir is only updated every two minutes, and to be nice, this integration will batch its updates every five minutes. If you add multiple sensors, the new sensors will take up to five minutes to get their data, as to not flood their free service with requests.

This component is licensed under the MIT license, so feel free to copy, enhance, and redistribute as you see fit.

Notes

This was a very single-day project, so it works for outdoor sensors that report an A and B channel. It should work with a single channel sensor as well, but I didn't test that.

This uses the free API to access the data. If you have your own sensors being published and have them marked as private, you'll need to modify this source to allow you to authenticate to view your data with your Google account (I think, it was mentioned in their FAQ).

I don't have any local devices, so this will not currently work with sensors on your internal network. It should be simple to add it, but I have no way to test it. It sounds like the payload is slightly different and the URL is private. This code simply extracts the given sensor ID to batch the /json requests (the site is hard-coded too, I just use the full URL to start).