You can configure all of the services you want later. When you first visit the page, you’ll see that a default application has already been created. We can use this for configuring our authorization. Click on the settings icon to open up the application settings where you’ll start setting up the connection between your Action and OAuth. You should take the time to consider which authentication solution makes the most sense for you. Auth0 is one example that provides many different authorization services, such as username/password and identity providers like Google Sign-In.

Authentication allows you to link your users' Google accounts with user accounts in your authentication system. This allows you to identify your users when your fulfillment receives a smart home intent. Google smart home only supports OAuth with an authorization code flow. Using this flow is discouraged because it requires transferring the user interaction from voice to screen. Google Sign-In for the Assistant provides the simplest and easiest user experience to users and developers both for account linking and account creation.
Implement OAuth account linking
First, you should create the project. This will create a project id, which you will use later in setting up your OAuth. Be inspired by top smart home brands who are delivering the best smart home experiences for their users on Google.
Use a JWT-decoding library for your language to decode the token, and use Google's public keys to verify the token's signature. Under Transition, select the Account Linking system scene. Increase token lifetime to greater than maintenance period. Maintain your existing service and route a limited number of requests to your newly updated service. Migrate all requests only after confirming expected functionality. Requests and replies can arrive in any order, or not at all due to asynchronous services running in a cluster, network behavior, or other means.
Complete account linking
When you have authenticated a user, the user's third-party OAuth 2.0 access token is sent in the authorization header when smart home intents are sent to your fulfillment. All users have to perform account linking, because device information is sent to the Assistant with the action.devices.SYNCintent, which requires account linking. A long-lived token that can be exchanged for a new access token when an access token expires. When your service integrates with Google, this token is exclusively stored and used by Google.

You should find information about what’s shared when you add someone to your home. When someone sends a request to join your home, you should receive an email with the invite request and a notification on your mobile device. Review what’s shared when you add someone to your home tap Next. To let other people, like family members or roommates, use the devices in your home, add them as home members.
Change a device’s room
To learn more, see the OAuth-based Google Sign-in "Streamlined" linking concept guideand implementation guide. From the Admin console dashboard, go to AppsAdditional Google services. In the newly created scene, click the add addicon for Conditions.

If the person you’re inviting is not already in your family group, you should be asked if you’d like to add them. To invite them to your family group, tap Add to Family.To skip this step, tapNo Thanks. Review the person’s access to your home tap Send. Enter the name or email address of the person you want to invite to your home tap Next. If asked, tap the room you want to move the device to Next.
Instructions for Google Workspace users
The OAuth linking type supports two industry standard OAuth 2.0 flows, the implicit and authorization code flows. This type of account linking is recommended if you have an existing authentication system and you want to allow users to connect to non @gmail.com addresses. Configure how the flow should proceed if the account linking flow can't be completed because of system or network errors. For example, send an acknowledging message and redirect to scenes that provide functionality that doesn't require account linking. Large companies with existing smart home products may already have an OAuth service and engineers who are able to keep it secure.

Every smart home Action must include a mechanism for authenticating users. Cloud-to-cloud Primer In-depth articles that cover the core concepts of smart home traits. Go to the third-party account where you linked your Google Account.
Your Google Account helps you save time by automatically filling in passwords, addresses, and payment details using the information you’ve saved to your account. They no longer have access to Nest Aware features, including video history. Your Google TV account isn't removed from this home. You have to sign out of this account on this home’s Google TVs or in account.google.com. You no longer have access to Nest Aware features, including video history.

When you sign in to your Google Account, all the Google services you use work together to help you get more done. For example, flight confirmations in your Gmail inbox will automatically sync with your Google Calendar and Google Maps to help you get to the airport on time. Other members continue to have access to Nest Aware features. To let the Google Assistant read or show results specific to you, you can choose to set up Voice Match and Face Match, and choose to turn on personal results. Review what’s shared when you join a home tap Agree. Follow the in-app instructions to join someone’s home.
Your service creates an access token and returns it to Google by redirecting the user's browser back to Google with the access token attached to the request. Exchanges a long-lived refresh token for a short-lived access token. This exchange happens when Google needs a new access token because the one it had expired. You must own, manage and maintain an OAuth 2.0 server which supports the OAuth 2.0 authorization code flow. To perform account linking with Google Sign-In, you ask the user to give consent to access their Google profile.
This is the basic OAuth flow that sends users to your website for linking. The user is redirected to your website to sign in to their account. Once signed in, the user consents to sharing their data, on your service, with Google. At that point, the user's Google Account and your service, are linked. Access to data and services hosted on your platform can be revoked byunlinking accounts.