Google Account 連結與 OAuth 型應用程式翻轉

OAuth-based App Flip Linking (App Flip) allows your users to easily and quickly link their accounts in your authentication system to their Google accounts. If your app is installed on your user’s phone when they initiate the account linking process, they are seamlessly flipped to your app to obtain user authorization.

This approach provides a faster and easier linking process since the user does not have to re-enter their username and password to authenticate; instead, App Flip leverages the credentials from the user's account on your app. Once a user has linked their Google account with your app, they can take advantage of any integrations that you have developed.

You can set up App Flip for both iOS and Android apps.

Figure 1. Account linking on a user's phone with App Flip.

Requirements

To implement App Flip, you must fulfill the following requirements:

• You must have an Android or iOS app.
• You must own, manage and maintain an OAuth 2.0 server which supports the OAuth 2.0 authorization code flow.

Note: Confirm that your OAuth2 implementation or provider supports the authorization code flow along with App Flip redirect URLs and client_ids as described in our guides.

Design guidelines

This section describes the design requirements and recommendations for the App Flip account linking consent screen. After Google calls your app, your app displays the consent screen to the user.

Requirements

1. You must communicate that the user’s account is being linked to Google, not to a specific Google product, such as Google Home or Google Assistant.

Recommendations

We recommend that you do the following:

1. Display Google's Privacy Policy. Include a link to Google’s Privacy Policy on the consent screen.

2. Data to be shared. Use clear and concise language to tell the user what data of theirs Google requires and why.

3. Clear call-to-action. State a clear call-to-action on your consent screen, such as “Agree and link.” This is because users need to understand what data they're required to share with Google to link their accounts.

4. Ability to cancel. Provide a way for users to go back or cancel, if they choose not to link.

5. Ability to unlink. Offer a mechanism for users to unlink, such as a URL to their account settings on your platform. Alternatively, you can include a link to Google Account where users can manage their linked account.

6. Ability to change user account. Suggest a method for users to switch their account(s). This is especially beneficial if users tend to have multiple accounts.

   • If a user must close the consent screen to switch accounts, send a recoverable error to Google so the user can sign in to the desired account with OAuth linking and the implicit flow.

7. Include your logo. Display your company logo on the consent screen. Use your style guidelines to place your logo. If you wish to also display Google's logo, see Logos and trademarks.

Figure 2. Account linking consent screen design guidelines.

在原生應用程式中實作應用程式轉換功能

如要導入應用程式翻轉功能，您必須修改應用程式中的使用者授權代碼，以便接受 Google 的深層連結。

如要支援 Android 應用程式的 App Flip 功能，請按照 Android 導入指南中的說明操作。

如要支援 iOS 應用程式的 App Flip 功能，請按照 iOS 導入指南中的說明操作。

測試應用程式翻轉

在可以使用通過驗證的正式版應用程式和有效的 OAuth 2.0 伺服器之前，系統可能會先使用範例和測試應用程式模擬應用程式翻轉功能。

在應用程式翻轉期間，Google 應用程式會先開啟應用程式，接著在 OAuth 2.0 伺服器上要求授權碼回應，最後一步則將回應傳回至 Google 應用程式。

必要條件

如要模擬 Google 應用程式並觸發會啟動應用程式的意圖，請下載並安裝 Android 和 iOS 應用程式翻轉應用程式測試工具。

下載並安裝 Android 版和 iOS 版應用程式翻轉範例，如要模擬應用程式並選取 OAuth 2.0 回應類型。

測試順序

1. 開啟應用程式翻轉測試工具。
2. 按下 Try Flip! 即可啟動 App Flip 範例應用程式。
3. 從「範例應用程式」的圓形按鈕中選取回應。
4. 按 Send 即可將模擬 OAuth 2.0 回應傳回測試工具。
5. 查看測試工具的記錄訊息，確認是否有 auth_code 或錯誤詳細資料。

正式版測試

完成註冊和 OAuth 2.0 伺服器實作後，即可在實際工作環境中測試應用程式翻轉功能。

建議您使用單一 Google 帳戶和工作專屬的電子郵件地址來自動測試。

以 Google 帳戶持有人身分登入時，您可以使用已連結帳戶查看帳戶連結狀態。您也可以在這些帳號中，反覆測試不同帳戶。

您也可以選擇實作 RISC，透過程式取消連結並通知 Google。