Temperature Collector

An AWS Lambda function that collects data from my thermostats and corresponding outdoor temperatures. It polls two different thermostat technologies, a Honeywell Gateway and a Google Nest, as well as the OpenWeather API. It's used to monitor conditions at The Grey Haven, an Airbnb in Lake Arrowhead, California.

Prerequisites

• Python 3
• terraform

Token Creation

First set up a project in the Google Device Access console. From there you will need the project ID, the client ID, and the client secret; copy them to a safe place.

Then run the following to open the Google login page.

utilities/open-login.py CLIENT_ID PROJECT_ID

Complete the login flow, and from the redirected URL, extract the code parameter and copy it to a safe place. Now run the following:

utilities/get-tokens.py CLIENT_ID CLIENT_SECRET CODE

Take the resultant refresh token from the above script, and copy it to a safe place.

Deployment

Deploy the Lambda by running terraform plan from the terraform folder. Once the infrastructure is deployed, modify the created temperature-collector-config secret and add the following values:

• greyHavenLocation: Comma-separated lat/lon of location of Airbnb
• sanDiegoLocation: Comma-separated lat/lon of location of home
• honeywellLocationId: Unique identifier for Honeywell Gateway (read out of console URL)
• honeywellLabels: Mapping of Honeywell zone IDs to zone names (formatted as key:value,key:value)
• honeywellUsername: Honeywell account username
• honeywellPassword: Honeywell account password
• nestProjectId: Project ID from earlier Google console step
• nestClientId: Client ID from earlier Google console step
• nestClientSecret: Client Secret from earlier Google console step
• nestRefreshToken: Refresh token output from earlier get-tokens.py script output
• openWeatherApiKey: OpenWeather API key from account page

Usage

Every five minutes the Lambda will be triggered, and write the following metrics to CloudWatch:

• Temperatures/SanDiego/Outside/Temperature
• Temperatures/SanDiego/Downstairs/Temperature
• Temperatures/SanDiego/Downstairs/HeatSetpoint
• Temperatures/SanDiego/Downstairs/CoolSetpoint
• Temperatures/TheGreyHaven/Outside/Temperature
• Temperatures/TheGreyHaven/Downstairs/Temperature
• Temperatures/TheGreyHaven/Downstairs/HeatSetpoint
• Temperatures/TheGreyHaven/Downstairs/CoolSetpoint
• Temperatures/TheGreyHaven/Upstairs/Temperature
• Temperatures/TheGreyHaven/Upstairs/HeatSetpoint
• Temperatures/TheGreyHaven/Upstairs/CoolSetpoint

To-Do

• Make the configuration of thermostats more generic, vs being specific to the author's setup.

• If Google ever gets around to implementing an API for the Nest remote temperature sensor it could be added here.