I'm following along with the instructions to https://www.home-assistant.io/integrations/google_assistant
I'm unable to get pass the Add a Cloud-to-Cloud integration step, after filling out all my details: Google responds cryptically with:
Request contains an invalid argument
I've attempted the process a half a dozen times, using three different projects, and even changing the logo without any luck.
My setup is using a reverse HTTPS proxy via Nginx that connects to my local Home Assistant over Tailscale [my ISP uses CG-NAT]. As far as I can tell everything has been configured correctly, and I'm able to login to HA from the public facing URL from both the web interface and phone app.
Here's what I'm using during the Google integration:
example = project id
https://oauth-redirect.googleusercontent.com/r/example
example.net = domain
https://example.net/auth/authorize
Returns: A themed Home Assistant with an error saying" "Invalid redirect URI"
Note: putting in a "fake" redirect URI in the query string will cause the HA login screen to display.
https://example.net/auth/token
Returns: 405: Method Not Allowed
https://example.net/api/google_assistant
Returns: 405: Method Not Allowed