I got a camera that has an interesting API to integrate into home automation systems. The problem is that it requires an HTTP endpoint in order to work. I am aware of the RESTful API of HA but to trigger services you need POST HTTP with payload and my camera just allows a GET request to a given URL.
I don’t know of any way of sending things to HA directly using HTTP GET commands - from what I can make of the document it expects a cgi script on the server.
But I think the documentation says you can send an e-mail on alarm, so you might be able to use the imap sensor