通过 OAuth 进行账号关联

OAuth 关联类型支持两种业界标准 OAuth 2.0 流程，即隐式和授权代码流程。

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.

实现 OAuth 账号关联

配置项目

如需将项目配置为使用 OAuth 关联，请按以下步骤操作：

  1. 打开 Actions 控制台，然后选择您要使用的项目。
  2. 点击开发标签页，然后选择帐号关联。
  3. 启用帐号关联旁边的开关。
  4. 在帐号创建部分，选择不，我只允许在我的网站上创建帐号。

  5. 在关联类型中，依次选择 OAuth 和隐式。

  6. 在客户信息中：

    • 为您的 Actions 向 Google 发出的客户端 ID 分配一个值，以标识来自 Google 的请求。
    • 插入授权端点和令牌交换端点的网址。
  1. 点击保存。

实现 OAuth 服务器

To support the OAuth 2.0 implicit flow, your service makes an authorization endpoint available by HTTPS. This endpoint is responsible for authenticating and 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.

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

A typical OAuth 2.0 implicit flow session initiated by Google has the following flow:

  1. Google opens your authorization endpoint in the user's browser. 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.
  2. 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.
  3. Google calls your service's APIs, and attaches the access token with each request. Your service verifies that the access token grants Google authorization to access the API and then completes the API call.

Handle authorization requests

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

Authorization endpoint parameters
client_id The client ID you assigned to Google.
redirect_uri The URL to which you send the response to this request.
state A bookkeeping value that is passed back to Google unchanged in the redirect URI.
response_type The type of value to return in the response. For the OAuth 2.0 implicit flow, the response type is always token.

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&response_type=token

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

  1. Verify the client_id and redirect_uri values to prevent granting access to unintended or misconfigured client apps:

    • Confirm that the client_id matches the client ID you assigned to Google.
    • 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.

  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 access token that Google will use to access your API. The access token can be any string value, but it must uniquely represent the user and the client the token is for and must not be guessable.

  4. Send an HTTP response that redirects the user's browser to the URL specified by the redirect_uri parameter. Include all of the following parameters in the URL fragment:

    • access_token: the access token you just generated
    • token_type: the string bearer
    • state: the unmodified state value from the original request The following is an example of the resulting URL: 
      https://oauth-redirect.googleusercontent.com/r/YOUR_PROJECT_ID#access_token=ACCESS_TOKEN&token_type=bearer&state=STATE_STRING

Google's OAuth 2.0 redirect handler will receive the access token and confirm that the state value hasn't changed. After Google has obtained an access token for your service, Google will attach the token to subsequent calls to your Action as part of the AppRequest.

为身份验证流程设计语音界面

检查用户是否已通过验证，并启动账号关联流程

  1. 在 Actions 控制台中打开您的 Actions Builder 项目。
  2. 创建一个新场景，以开始在您的 Action 中关联帐号：
    1. 点击 Scenes。
    2. 点击添加 (+) 图标以添加新场景。
  3. 在新创建的场景中，点击条件对应的添加 图标。
  4. 添加一个条件，用于检查与对话关联的用户是否为经过验证的用户。如果检查失败，您的 Action 无法在对话期间执行帐号关联，而应回退以提供对不需要帐号关联的功能的访问权限。
    1. 在条件下的 Enter new expression 字段中，输入以下逻辑：user.verificationStatus != "VERIFIED"
    2. 在 Transition 下，选择不需要帐号关联的场景，或选择访客专享功能的入口点。

  1. 点击条件对应的添加 图标。
  2. 添加一个条件，以便在用户没有关联的身份时触发帐号关联流程。
    1. 在条件下的 Enter new expression 字段中，输入以下逻辑：user.verificationStatus == "VERIFIED"
    2. 在转换下，选择帐号关联系统场景。
    3. 点击保存。

保存后，系统会将一个名为 <SceneName>_AccountLinking 的新帐号关联系统场景添加到您的项目中。

自定义账号关联场景

  1. 在 Scenes 下，选择帐号关联系统场景。
  2. 点击发送提示并添加一小句话，向用户说明该 Action 为何需要访问其身份（例如“保存您的偏好设置”）。
  3. 点击保存。

  1. 在条件下，点击如果用户成功完成帐号关联。
  2. 配置当用户同意关联其账号时该流程应如何处理。 例如，调用网络钩子以处理所需的任何自定义业务逻辑，并转换回原始场景。
  3. 点击保存。

  1. 在条件下方，点击如果用户取消或忽略帐号关联。
  2. 配置如果用户不同意关联其帐号，相应流程应如何处理。例如，发送确认消息并重定向到提供无需进行帐号关联的功能的场景。
  3. 点击保存。

  1. 在条件下方，点击如果出现系统或网络错误。
  2. 配置帐号关联流程因系统或网络错误而无法完成时应采取的流程。例如，发送确认消息并重定向到提供无需进行帐号关联的功能的场景。
  3. 点击保存。

处理数据访问请求

如果 Google 助理请求包含访问令牌，请先检查访问令牌是否有效（且未过期），然后从数据库中检索关联的用户帐号。