[NEST INTEGRATION] Getting a Error 400: redirect_uri_mismatch when trying to use OAuth2 with Google (former NEST)

I am getting an Error 400: redirect_uri_mismatch when trying to use OAuth2 to connect my NEST thermostat through my Google account.

Google recently reopened its Developer APIs again at a small up-front cost. I am using this option and the same procedure documented under the Google Assistant integration to install the integration with my NEST Thermostat using the Google account (my old NEST account was migrated to Google).

Has anyone here tried to connect HomeAssistant with NEST recently to give me some help? I tried to use my DDNS URL and a blank URL as the REDIRECT URL but nothing seems to work.

Any help would be greatly appreciated.

The integration does not work with the new Google/Nest APIs (yet). The new API uses tokens (access_token, refresh_token, etc.) not PIN codes.

Thank you, Brandon. Do you know if this is in the product roadmap? I was wondering how many more months I will need to wait until a solution is available.


Can’t say for certain. The API was just released so it’s really just a matter of when developers get around to implementing it. The documentation looks solid so I don’t imagine it’d be too long. I wrote an Android app that grabs my thermostat and camera data from it but I haven’t taken the time to learn how to write HA integrations yet.

It’s now November 5th and it still doesn’t work: pensive:
I am trying to add a Nest Smoke Detector in Google Home, but unfortunately I still get the Error 400 message.
Anyone any idea when this is going to work?

Here is a video how to make it work

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