Associer des comptes avec OAuth

Le type d'association OAuth est compatible avec deux flux OAuth 2.0 standards dans l'industrie, les flux de code implicite et autorisation.

In the implicit code flow, Google opens your authorization endpoint in the user's browser. After successful sign in, you return a long-lived access token to Google. This access token is now included in every request sent from the Assistant to your Action.

In the authorization code flow, you need two endpoints:

• The authorization endpoint, which is responsible for presenting the sign-in UI to your users that aren't already signed in and recording consent to the requested access in the form of a short-lived authorization code.
• The token exchange endpoint, which is responsible for two types of exchanges:
  1. Exchanges an authorization code for a long-lived refresh token and a short-lived access token. This exchange happens when the user goes through the account linking flow.
  2. 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.

Although the implicit code flow is simpler to implement, Google recommends that access tokens issued using the implicit flow never expire, because using token expiration with the implicit flow forces the user to link their account again. If you need token expiration for security reasons, you should strongly consider using the auth code flow instead.

Implémenter l'association de compte OAuth

Configurer le projet

Pour configurer votre projet afin d'utiliser l'association OAuth, procédez comme suit:

1. Ouvrez la console Actions et sélectionnez le projet que vous souhaitez utiliser.
2. Cliquez sur l'onglet Développer, puis sélectionnez Association de comptes.
3. Activez le bouton bascule à côté de Association de comptes.
4. Dans la section Création de compte, sélectionnez Non, je souhaite uniquement autoriser la création de comptes sur mon site Web.

5. Dans Type d'association, sélectionnez OAuth et Code d'autorisation.

   

6. Dans Informations client:

   • Attribuez une valeur au Client-ID émis par vos actions vers Google pour identifier les requêtes provenant de Google.
   • Notez la valeur de l'ID client émis par Google pour vos actions.
   • Insérez les URL de vos points de terminaison Autorisation et Token Exchange.

6. Cliquez sur Enregistrer.

Implémenter votre serveur OAuth

An OAuth 2.0 server implementation of the authorization code flow consists of two endpoints, which your service makes available by HTTPS. The first endpoint is the authorization endpoint, which is responsible for finding or obtaining consent from users for data access. The authorization endpoint presents a sign-in UI to your users that aren't already signed in and records consent to the requested access. The second endpoint is the token exchange endpoint, which is used to obtain encrypted strings called tokens that authorize the Action user to access your service.

When your Action needs to call one of your service's APIs, Google uses these endpoints together to get permission from your users to call these APIs on their behalf.

OAuth 2.0 auth code flow session initiated by Google has the following flow:

1. Google opens your authorization endpoint in the user's browser. If the flow started on a voice-only device for an Action, Google would transfer the execution to a phone.

2. The user signs in (if not signed in already) and grants Google permission to access their data with your API if they haven't already granted permission.

3. Your service creates an authorization code and returns it to Google by redirecting the user's browser back to Google with the authorization code attached to the request.

4. Google sends the authorization code to your token exchange endpoint, which verifies the authenticity of the code and returns an access token and a refresh token. The access token is a short-lived token that your service accepts as credentials to access APIs. The refresh token is a long-lived token that Google can store and use to acquire new access tokens when they expire.

5. After the user has completed the account linking flow, every subsequent request sent from the Assistant to your fulfillment webhook contains an access token.

Handle authorization requests

When your Action needs to perform account linking via an OAuth 2.0 authorization code flow, Google sends the user to your authorization endpoint with a request that includes the following parameters:

For example, if your authorization endpoint is available at https://myservice.example.com/auth, a request might look like:

GET https://myservice.example.com/auth?client_id=GOOGLE_CLIENT_ID&redirect_uri=REDIRECT_URI&state=STATE_STRING&scope=REQUESTED_SCOPES&response_type=code

For your authorization endpoint to handle sign-in requests, do the following steps:

1. Verify that the client_id matches the Google client ID you registered with Google, and that the redirect_uri matches the redirect URL provided by Google for your service. These checks are important to prevent granting access to unintended or misconfigured client apps.

   If you support multiple OAuth 2.0 flows, also confirm that the response_type is code.

2. Check if the user is signed in to your service. If the user isn't signed in, complete your service's sign-in or sign-up flow.

3. Generate an authorization code that Google will use to access your API. The authorization code can be any string value, but it must uniquely represent the user, the client the token is for, and the code's expiration time, and it must not be guessable. You typically issue authorization codes that expire after approximately 10 minutes.

4. Confirm that the URL specified by the redirect_uri parameter has the following form:

   https://oauth-redirect.googleusercontent.com/r/YOUR_PROJECT_ID

   YOUR_PROJECT_ID is the ID found on the Project settings page of the Actions Console.

5. Redirect the user's browser to the URL specified by the redirect_uri parameter. Include the authorization code you just generated and the original, unmodified state value when you redirect by appending the code and state parameters. The following is an example of the resulting URL:

   https://oauth-redirect.googleusercontent.com/r/YOUR_PROJECT_ID?code=AUTHORIZATION_CODE&state=STATE_STRING

Handle token exchange requests

Your service's token exchange endpoint is responsible for two kinds of token exchanges:

• Exchange authorization codes for access tokens and refresh tokens
• Exchange refresh tokens for access tokens

Token exchange requests include the following parameters:

Exchange authorization codes for access tokens and refresh tokens

After the user signs in and your authorization endpoint returns a short-lived authorization code to Google, Google sends a request to your token exchange endpoint to exchange the authorization code for an access token and a refresh token.

For these requests, the value of grant_type is authorization_code, and the value of code is the value of the authorization code you previously granted to Google. The following is an example of a request to exchange an authorization code for an access token and a refresh token:

POST /token HTTP/1.1
Host: oauth2.example.com
Content-Type: application/x-www-form-urlencoded

client_id=GOOGLE_CLIENT_ID&client_secret=GOOGLE_CLIENT_SECRET&grant_type=authorization_code&code=AUTHORIZATION_CODE&redirect_uri=REDIRECT_URI

To exchange authorization codes for an access token and a refresh token, your token exchange endpoint responds to POST requests executing the following steps:

1. Verify that the client_id identifies the request origin as an authorized origin, and that the client_secret matches the expected value.
2. Verify the following:
   • The authorization code is valid and not expired, and the client ID specified in the request matches the client ID associated with the authorization code.
   • The URL specified by the redirect_uri parameter is identical to the value used in the initial authorization request.
3. If you cannot verify all of the above criteria, return an HTTP 400 Bad Request error with {"error": "invalid_grant"} as the body.
4. Otherwise, using the user ID from the authorization code, generate a refresh token and an access token. These tokens can be any string value, but they must uniquely represent the user and the client the token is for, and they must not be guessable. For access tokens, also record the expiration time of the token (typically an hour after you issue the token). Refresh tokens do not expire.
5. Return the following JSON object in the body of the HTTPS response:

   {
   "token_type": "Bearer",
   "access_token": "ACCESS_TOKEN",
   "refresh_token": "REFRESH_TOKEN",
   "expires_in": SECONDS_TO_EXPIRATION
   }

Google stores the access token and the refresh token for the user and records the expiration of the access token. When the access token expires, Google uses the refresh token to get a new access token from your token exchange endpoint.

Exchange refresh tokens for access tokens

When an access token expires, Google sends a request to your token exchange endpoint to exchange a refresh token for a new access token.

For these requests, the value of grant_type is refresh_token, and the value of refresh_token is the value of the refresh token you previously granted to Google. The following is an example of a request to exchange a refresh token for an access token:

POST /token HTTP/1.1
Host: oauth2.example.com
Content-Type: application/x-www-form-urlencoded

client_id=GOOGLE_CLIENT_ID&client_secret=GOOGLE_CLIENT_SECRET&grant_type=refresh_token&refresh_token=REFRESH_TOKEN

To exchange a refresh token for an access token, your token exchange endpoint responds to POST requests executing the following steps:

1. Verify that the client_id identifies the request origin as Google, and that the client_secret matches the expected value.
2. Verify that the refresh token is valid, and that the client ID specified in the request matches the client ID associated with the refresh token.
3. If you cannot verify all of the above criteria, return an HTTP 400 Bad Request error with {"error": "invalid_grant"} as the body.
4. Otherwise, use the user ID from the refresh token to generate an access token. These tokens can be any string value, but they must uniquely represent the user and the client the token is for, and they must not be guessable. For access tokens, also record the expiration time of the token (typically an hour after you issue the token).
5. Return the following JSON object in the body of the HTTPS response:

   {
   "token_type": "Bearer",
   "access_token": "ACCESS_TOKEN",
   "expires_in": SECONDS_TO_EXPIRATION
   }

Concevoir l'interface utilisateur vocale pour le flux d'authentification

Vérifier si l'utilisateur est validé et démarrer le flux d'association de compte

1. Ouvrez votre projet Actions Builder dans la console Actions.
2. Créez une scène pour lancer l'association de comptes dans votre action :
   1. Cliquez sur Scenes (Scènes).
   2. Cliquez sur l'icône d'ajout (+) pour ajouter une scène.
3. Dans la scène que vous venez de créer, cliquez sur l'icône d'ajout add pour Conditions.
4. Ajoutez une condition qui vérifie si l'utilisateur associé à la conversation est un utilisateur validé. Si la vérification échoue, votre action ne peut pas associer de compte pendant la conversation. Elle doit alors fournir l'accès à des fonctionnalités qui ne nécessitent pas d'association de compte.
   1. Dans le champ Enter new expression, sous Condition, saisissez la logique suivante : user.verificationStatus != "VERIFIED"
   2. Sous Transition, sélectionnez une scène ne nécessitant pas d'association de compte ou une scène qui est le point d'entrée de la fonctionnalité Invité.

1. Cliquez sur l'icône d'ajout add pour Conditions.
2. Ajoutez une condition pour déclencher un flux d'association de compte si l'utilisateur n'est associé à aucune identité.
   1. Dans le champ Enter new expression, sous Condition, saisissez la logique suivante : user.verificationStatus == "VERIFIED"
   2. Sous Transition, sélectionnez la scène système Association de comptes.
   3. Cliquez sur Enregistrer.

Après l'enregistrement, une nouvelle scène système d'association de comptes appelée <SceneName>_AccountLinking est ajoutée à votre projet.

Personnaliser la scène de l'association de comptes

1. Sous Scenes (Scènes), sélectionnez la scène du système d'association de comptes.
2. Cliquez sur Envoyer une invite et ajoutez une courte phrase pour expliquer à l'utilisateur pourquoi l'action doit accéder à son identité (par exemple, "Enregistrer vos préférences").
3. Cliquez sur Enregistrer.

1. Sous Conditions, cliquez sur Si l'utilisateur a correctement associé ses comptes.
2. Configurez le déroulement du flux si l'utilisateur accepte d'associer son compte. Par exemple, appelez le webhook pour traiter toute logique métier personnalisée requise et revenir à la scène d'origine.
3. Cliquez sur Enregistrer.

1. Sous Conditions, cliquez sur Si l'utilisateur annule ou ignore l'association de comptes.
2. Configurez le déroulement du flux si l'utilisateur n'accepte pas d'associer son compte. Par exemple, envoyez un message de confirmation et redirigez vers des scènes qui fournissent des fonctionnalités qui ne nécessitent pas d'association de compte.
3. Cliquez sur Enregistrer.

1. Sous Conditions, cliquez sur Si une erreur système ou réseau se produit.
2. Configurez la manière dont le flux doit se dérouler si le flux d'association de comptes ne peut pas être terminé en raison d'erreurs système ou réseau. Par exemple, envoyez un message de confirmation et redirigez vers des scènes qui fournissent des fonctionnalités qui ne nécessitent pas d'association de compte.
3. Cliquez sur Enregistrer.

Gérer les demandes d'accès aux données

Si la requête de l'Assistant contient un jeton d'accès, vérifiez d'abord que le jeton est valide (et qu'il n'a pas expiré), puis récupérez le compte utilisateur associé dans votre base de données.