Triggering an Alexa routine from the command line or an Arduino compatible device (ESP32)


By creating an auto-resetting virtual sensor on SmartThings.com, Alexa can execute a routine when the virtual sensor's state is triggered via a REST call to SmartThings.com

Steps to follow

Creating a virtual, auto-resetting sensor on SmartThings.com

  • Register an account with SmartThings.com
  • Go to My device handlers
  • Create a new device handler 
  • Switch to "From code" and paste in the auto-resetting sensor code from here.
  • Go to My Locations and add a new location (e.g., "Living Room")
  • Go to My Devices and add a new device
    • Name, Label, Zigbee Id, Device Network Id = MyVirtualButton
    • Type = Simulated Alexa Button (probably the last item in the dropdown)
    • Location = Living Room (or whatever you created)
    • Hub, Group = (empty)
  • Once you created the device, click on it and make sure to take a note of the GUID in the URL, which will look something like this (the last part, c00... is the GUID of the device): /device/show/c00ab333-71e6-4a62-9c39-5df269cddd95

Create a personal access token for SmartThings.com

Making the first call to SmartThings.com from the command line

To make sure everything works so far, execute the following curl command (substitute your GUIDs):

curl -H 'Authorization: Bearer: YOUR_PERSONAL_ACCESS_TOKEN' \
-d '[{"component":"main","capability":"switch","command":"on"}]' \
https://api.smartthings.com/v1/devices/YOUR_DEVICE_GUID/commands

Then something like this should come back:

{"results":[{"id":"fffb05cb-16fd-4c0c-a1de-24ab0e96b0ba","status":"ACCEPTED"}]}

Setting up Alexa

  • Install the SmartThings skills on your Alexa account
  • Discover new devices - this should find your new MyVirtualButton sensor (note: we had to create a sensor rather than a simple switch: Alexa cannot trigger routines based on switches, only based on sensors).
  • Create a new Alexa routine that is triggered by MyVirtualButton: "When MyVirtualButton is..." "Open"

Triggering the virtual sensor from your Arduino device

The last step is to write a simple HTTP POST call -replacing the curl command above- in C to call SmartThings.com with the right personal token and device id. The complete Arduino code to trigger an Alexa routine can be found here.



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