I am currently working on tool that will send an automated message broadcast to all Google Homes in my home. I want to run this tool on a VPS, but unfortunately the Google Assistant SDK only supports broadcasting to Google Homes on the same Wi-Fi network.
However, the Google Assistant app on my phone has no problem broadcasting a message to all my Google Homes, even when I am miles away from my house. So, I am attempting to recreate this effect so that my VPS can broadcast messages to my Google Homes.
I know the Google Assistant SDK endpoint is embeddedassistant.googleapis.com, but I do not know the endpoint that is used by the actual app. I tried decompiling the app to find it, but to no avail.
I assume the actual phone app uses a separate endpoint (and internal API) than the app, but I am still trying to find out what it is.
Any help on this would be much appreciated!
After some digging, it appears the Google App's internal API endpoint is:
https://www.google.com/m/voice-search/up?pair=[Request_ID]
However, the endpoint does not appear to use protocol buffers and uses a content type called application/vnd.google.octet-stream-compressible
The only information I could find is available here (with Google Translate): https://yangwenbo.com/articles/google-app-api-protocol-voice-search.html