I’m using a ZigBee button to call an automation which notifies via Pushover and Alexa. Works fine.
I’d like to reduce latency and use a physical button. I can use a Pi, ESP32 or similar to respond to a closure and tell HA.
What’s the lowest latency input to HA? My MQTT server is separate so I’m thinking an HTTP post direct into HA might be best.
Is there anything faster? HTTP is fast enough in my testing, it’s an experiment as much as anything else.
I have a wired device sending HTTP POST updates very regularly (often more than one per second) and if I watch those arrive, they appear almost instantaneous. If the sending device used IP (or, more likely, had cached the lookup) I guess that would be fast too.
Good point about the MQTT persistence, cheers.
Practically it doesn’t make any real difference - unless your network is ancient/massively overloaded/completely screwed or your client device is low power enough to struggle with TLS the whole connection setup process is only going to take ~100ms at most