Hi everyone,
I’m trying to get the Nest integration working using the OAuth method, but I keep getting stuck after the account linking step. After the OAuth flow completes, I get this error in Home Assistant:
Configuration error creating subscription:
Failed to create subscriber 'projects/[my-project]/subscriptions/home-assistant-xyz'
(cloud project id incorrect?)
What’s Working:
- OAuth consent screen + credentials created in Google Cloud Console.
- Smart Device Management API and Pub/Sub API are enabled.
- I manually created the Pub/Sub topic and subscription, and verified they’re active.
- I’ve assigned all necessary IAM roles (subscriber, token creator, etc.) to the service account.
- I’m using HTTPS via DuckDNS with a valid cert.
- External access works fine (e.g. https://mydomain.duckdns.org:8123).
- I go through the “Link account to Home Assistant” flow and the redirect works.
Where It Fails:
- HA can’t seem to link the Pub/Sub topic.
- I’ve tried creating the subscription manually and letting HA create it — same result.
- Logs always show a cloud project id incorrect? error.
- I realized the Device Access Console (DAC) uses a different project ID than my main GCP project where everything is configured.
- There doesn’t seem to be a way to realign or change the DAC project ID.
The Big Question:
Has anyone successfully completed the Nest OAuth integration using a different GCP project than the one DAC auto-generates?
Or is it now required to:
- Create the OAuth client ID,
- Enable APIs, and
- Create Pub/Sub…all in the exact same project created in the DAC ?
Thanks in advance for any clarity — happy to provide more sanitized logs or screenshots if helpful.