Sketch Request: Device IDs with Server Side Push Event

[youmustfight]

In a world where multiple devices are deployed, how can a device create a unique identifier for itself? This may be useful for notifications. It'd be great to have an example where an ID is initiated by a device, some sort of non-blocking polling is implemented, and if some event is present (for now API can just randomly create an event body), we can do a series of LED blinks.

This seems straight forward, but maybe there's some nuance edge cases that can be explored.