1 Goal is to receive push notifications when the ten minutes rolling average of PM2.5 density as measured by one PurpleAir device crosses a threshold. After that you may want to switch on the air purifier.
3 The Ruby script is intended to run through:
5 - a scheduler (cron, Heroku Scheduler, ...)
9 Set IRON_CACHE_PROJECT_ID and IRON_CACHE_TOKEN env variables.
10 Discord Webhook URL ('WEBHOOK_URL') and one PurpleAir JSON interface ('uri') must be set as well.
12 Discord iOS app doesn't require to run in background. Push notifications work well if Discord server for some reasons doesn't miss to receive the message. Sometimes does.
14 Each value, excluding Temperature, is presented in a range derived from the sensor published accuracy. No measure is without errors.