If you have a hub, you can install the [ST Edge] Web Requestor: a driver to issue local POST and GET HTTP requests Edge driver which can do what you want. You do have to run a local proxy server since hubs can only talk to local LAN devices and not to the Internet. With this method, you would use ST Routines to trigger the action based on a specific state change specified in the Routine.
If you don’t have a hub, you could use the 3rd party rules engine sharptools.io to do the http GET/POST and in their rules engine you can specify a trigger of any change to a particular attribute such as switch, switchLevel, etc.
