透過 OAuth 連結帳戶

OAuth 連結類型支援兩種符合業界標準的 OAuth 2.0 流程,分別是隱含授權碼流程。

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.

實作 OAuth 帳戶連結

設定專案

如要設定專案以使用 OAuth 連結,請按照下列步驟操作:

  1. 開啟 Actions 管理中心,然後選取要使用的專案。
  2. 按一下「開發」分頁,然後選擇「帳戶連結」
  3. 啟用「帳戶連結」旁的切換鈕。
  4. 在「帳戶建立」部分,選取「否,我只想允許在我的網站上建立帳戶」

  5. 在「連結類型」中,選取「OAuth」和「隱含」

  6. 在「用戶端資訊」中:

    • 為「Google 簽發給動作的用戶端 ID」指派值,以識別來自 Google 的要求。
    • 插入授權和權杖交換端點的網址。
  1. 按一下 [儲存]

導入 OAuth 伺服器

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.

設計驗證流程的語音使用者介面

檢查使用者是否已通過驗證,然後開始帳戶連結流程

  1. Actions Console 中開啟 Actions Builder 專案。
  2. 在動作中建立新場景,開始連結帳戶:
    1. 按一下「場景」
    2. 按一下「新增」 (+) 圖示,即可新增場景。
  3. 在新建立的場景中,按一下「條件」的「新增」圖示
  4. 新增條件,檢查與對話相關聯的使用者是否為已驗證使用者。如果檢查失敗,動作就無法在對話期間執行帳戶連結,且應改為提供不需要帳戶連結的功能存取權。
    1. 在「條件」下方的 Enter new expression 欄位中,輸入下列邏輯: user.verificationStatus != "VERIFIED"
    2. 在「轉場效果」下方,選取不需要連結帳戶的場景,或是僅限訪客使用的功能進入點場景。

  1. 按一下「條件」的「新增」圖示。
  2. 新增條件,在使用者沒有相關聯的身分時觸發帳戶連結流程。
    1. 在「條件」下方的 Enter new expression 欄位中,輸入下列邏輯: user.verificationStatus == "VERIFIED"
    2. 在「Transition」下方,選取「Account Linking」系統場景。
    3. 按一下 [儲存]

儲存後,專案中會新增名為「<SceneName>_AccountLinking」的帳戶連結系統場景。

自訂帳戶連結場景

  1. 在「場景」下方,選取帳戶連結系統場景。
  2. 按一下「傳送提示」,並新增簡短句子,向使用者說明動作為何需要存取身分識別資訊 (例如「儲存偏好設定」)。
  3. 按一下 [儲存]

  1. 按一下「條件」下方的「如果使用者成功完成帳戶連結」
  2. 設定使用者同意連結帳戶時,流程應如何繼續進行。 舉例來說,呼叫 Webhook 來處理任何必要的自訂商業邏輯,然後返回原始場景。
  3. 按一下 [儲存]

  1. 在「條件」下方,按一下「如果使用者取消或關閉帳戶連結」。
  2. 設定使用者不同意連結帳戶時,流程應如何進行。舉例來說,傳送確認訊息,然後重新導向至不需要帳戶連結的功能場景。
  3. 按一下 [儲存]

  1. 在「條件」下方,按一下「如果發生系統或網路錯誤」
  2. 設定帳戶連結流程因系統或網路錯誤而無法完成時,流程應如何繼續。舉例來說,傳送確認訊息,然後重新導向至不需要帳戶連結的功能場景。
  3. 按一下 [儲存]

處理資料存取要求

如果Google 助理要求包含存取權杖,請先檢查存取權杖是否有效 (未過期),然後從資料庫中擷取相關聯的使用者帳戶。