帐号使用行业标准的 OAuth 2.0 隐式和授权代码流程来关联。您的服务必须支持符合 OAuth 2.0 规范的授权和令牌交换端点。
In the implicit 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 Google.
In the authorization code flow, you need two endpoints:
The authorization endpoint, which presents the sign-in UI to your users that aren't already signed in. The authorization endpoint also creates a short-lived authorization code to record users' consent to the requested access.
The token exchange endpoint, which is responsible for two types of exchanges:
- 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.
- 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.
Choose an OAuth 2.0 flow
Although the implicit flow is simpler to implement, Google recommends that access tokens issued by the implicit flow never expire. This is because the user is forced to link their account again after a token expires with the implicit flow. If you need token expiration for security reasons, we strongly recommend that you use the authorization code flow instead.
Design guidelines
This section describes the design requirements and recommendations for the user screen that you host for OAuth linking flows. After it's called by Google's app, your platform displays a sign in to Google page and account linking consent screen to the user. The user is directed back to Google's app after giving their consent to link accounts.
![This figure shows the steps for a user to link their Google account
to your authentication system. The first screenshot shows
user-initiated linking from your platform. The second image shows
user sign-in to Google, while the third shows the user consent and
confirmation for linking their Google account with your app. The
final screenshot shows a successfully linked user account in the
Google app.](https://developers.google.cn/static/identity/images/oauth-linking-flow.png?authuser=1&hl=lt)
Requirements
- You must communicate that the user’s account will be linked to Google, not a specific Google product like Google Home or Google Assistant.
Recommendations
We recommend that you do the following:
Display Google's Privacy Policy. Include a link to Google’s Privacy Policy on the consent screen.
Data to be shared. Use clear and concise language to tell the user what data of theirs Google requires and why.
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.
Ability to cancel. Provide a way for users to go back or cancel, if they choose not to link.
Clear sign-in process. Ensure that users have clear method for signing in to their Google account, such as fields for their username and password or Sign in with Google.
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.
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.
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.
![This figure shows example user sign in and consent screens with
call-outs to the individual requirements and recommendations to
follow when you design a user sign in and consent screen.](https://developers.google.cn/static/identity/images/oauth-linking-consent.png?authuser=1&hl=lt)
创建项目
如需创建项目以使用帐号关联,请按以下步骤操作:
- Go to the Google API Console.
- 单击创建项目 。
- 输入名称或接受生成的建议。
- 确认或编辑所有剩余字段。
- 点击创建 。
要查看您的项目ID:
- Go to the Google API Console.
- 在登录页面的表格中找到您的项目。项目ID出现在ID列中。
配置 OAuth 权限请求页面
Google 帐号关联流程包括一个同意屏幕,用于告知用户请求访问其数据的应用、用户要求的数据类型以及适用的条款。您需要先配置 OAuth 权限请求页面,然后才能生成 Google API 客户端 ID。
- 打开 Google API 控制台的 OAuth 同意屏幕页面。
- 如果出现提示,请选择您刚刚创建的项目。
在“OAuth 同意屏幕”页面上,填写表单,然后点击“保存”按钮。
应用名称:请求用户同意的应用的名称。该名称应准确反映您的应用,并与用户在别处看到的应用名称保持一致。应用名称将显示在帐号关联同意屏幕上。
应用徽标:同意屏幕上的图片,有助于用户识别您的应用。徽标会显示在帐号关联同意屏幕和帐号设置中
支持电子邮件地址:供用户就其同意情况与您联系。
Google API 的范围:范围允许您的应用访问用户的私有 Google 数据。对于 Google 帐号关联用例,默认范围(电子邮件、个人资料、OpenID)就足够了,您无需添加任何敏感范围。最佳做法一般是在需要访问时逐步请求作用域,而不是预先请求。了解详情。
已获授权的网域:为保护您和您的用户,Google 仅允许使用 OAuth 进行身份验证的应用使用已获授权的网域。您应用的链接必须托管在已获授权的网域上。了解详情。
应用首页链接:您的应用的首页。必须托管在已获授权的网域上。
应用隐私权政策链接:在 Google 帐号关联同意屏幕上显示。必须托管在已获授权的网域上。
应用服务条款链接(可选):必须托管在已获授权的网域上。
图 1. 一款虚构应用 Tunery 的 Google 帐号关联同意屏幕
查看“验证状态”。如果您的申请需要验证,请点击“提交验证”按钮,提交您的申请。如需了解详情,请参阅 OAuth 验证要求。
实现 OAuth 服务器
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 a user to access your service.
When a Google application 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.
An OAuth 2.0 authorization code flow session initiated by Google has the following flow:
- Google opens your authorization endpoint in the user's browser. If the flow started on a voice-only device for an Action, Google transfers the execution to a phone.
- 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.
- Your service creates an authorization code and returns it to Google. To do so, redirect the user's browser back to Google with the authorization code attached to the request.
- 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.
- After the user has completed the account linking flow, every subsequent request sent from Google contains an access token.
Handle authorization requests
When you need to perform account linking using the OAuth 2.0 authorization code 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. |
scope |
Optional: A space-delimited set of scope strings that specify the data Google is requesting authorization for. |
response_type |
The type of value to return in the response. For the OAuth 2.0
authorization code flow, the response type is always code .
|
user_locale |
The Google Account language setting in RFC5646 format, used to localize your content in the user's preferred language. |
For example, if your authorization endpoint is available at
https://myservice.example.com/auth
, a request might look like the following:
GET https://myservice.example.com/auth?client_id=GOOGLE_CLIENT_ID&redirect_uri=REDIRECT_URI&state=STATE_STRING&scope=REQUESTED_SCOPES&response_type=code&user_locale=LOCALE
For your authorization endpoint to handle sign-in requests, do the following steps:
- Verify that the
client_id
matches the Client ID you assigned to Google, and that theredirect_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 theresponse_type
iscode
. - 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.
- Generate an authorization code for Google to 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.
- Confirm that the URL specified by the
redirect_uri
parameter has the following form:https://oauth-redirect.googleusercontent.com/r/YOUR_PROJECT_ID https://oauth-redirect-sandbox.googleusercontent.com/r/YOUR_PROJECT_ID
- 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 thecode
andstate
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:
Token exchange endpoint parameters | |
---|---|
client_id |
A string that identifies the request origin as Google. This string must be registered within your system as Google's unique identifier. |
client_secret |
A secret string that you registered with Google for your service. |
grant_type |
The type of token being exchanged. It's either
authorization_code or refresh_token . |
code |
When grant_type=authorization_code , this parameter is the
code Google received from either your sign-in or token exchange
endpoint. |
redirect_uri |
When grant_type=authorization_code , this parameter is the
URL used in the initial authorization request. |
refresh_token |
When grant_type=refresh_token , this parameter is the
refresh token Google received from your token exchange endpoint. |
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 by executing the following
steps:
- Verify that the
client_id
identifies the request origin as an authorized origin, and that theclient_secret
matches the expected value. - Verify that the authorization code is valid and not expired, and that the client ID specified in the request matches the client ID associated with the authorization code.
- Confirm that the URL specified by the
redirect_uri
parameter is identical to the value used in the initial authorization request. - If you can't verify all of the above criteria, return an HTTP
400 Bad Request error with
{"error": "invalid_grant"}
as the body. - Otherwise, use the user ID from the authorization code to 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, which is typically an hour after you issue the token. Refresh tokens don't expire.
- 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 by executing the following steps:
- Verify that the
client_id
identifies the request origin as Google, and that theclient_secret
matches the expected value. - 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.
- If you can't verify all of the above criteria, return an HTTP 400
Bad Request error with
{"error": "invalid_grant"}
as the body. - 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.
- Return the following JSON object in the body of the HTTPS
response:
{ "token_type": "Bearer", "access_token": "ACCESS_TOKEN", "expires_in": SECONDS_TO_EXPIRATION }
处理 userinfo 请求
userinfo 端点是受 OAuth 2.0 保护的资源,会返回关联用户的声明。实现和托管 userinfo 端点是可选的,但以下用例除外:
从您的令牌端点成功检索到访问令牌后,Google 会向您的 userinfo 端点发送请求,以检索关联用户的基本个人资料信息。
userinfo 端点请求标头 | |
---|---|
Authorization header |
Bearer 类型的访问令牌。 |
例如,如果您的 userinfo 端点可通过
https://myservice.example.com/userinfo
时,请求可能如下所示:
GET /userinfo HTTP/1.1 Host: myservice.example.com Authorization: Bearer ACCESS_TOKEN
为了让 userinfo 端点能够处理请求,请执行以下步骤:
- 从 Authorization 标头中提取访问令牌,并返回与访问令牌相关联的用户的信息。
- 如果访问令牌无效,则使用
WWW-Authenticate
响应标头返回 HTTP 401 Unauthorized 错误。下面是一个 userinfo 错误响应示例:HTTP/1.1 401 Unauthorized WWW-Authenticate: error="invalid_token", error_description="The Access Token expired"
如果在关联过程中返回 401 未经授权错误或任何其他失败的错误响应,该错误将无法恢复,检索到的令牌将被舍弃,并且用户必须重新开始关联流程。 如果访问令牌有效,则返回 HTTPS 正文中包含以下 JSON 对象的 HTTP 200 响应 回复:
{ "sub": "USER_UUID", "email": "EMAIL_ADDRESS", "given_name": "FIRST_NAME", "family_name": "LAST_NAME", "name": "FULL_NAME", "picture": "PROFILE_PICTURE", }
如果您的 userinfo 端点返回 HTTP 200 成功响应,则系统会针对用户的 Google 账号注册检索到的令牌和声明。userinfo 端点响应 sub
系统中用于识别用户的唯一 ID。 email
用户的电子邮件地址。 given_name
可选:用户的名字。 family_name
可选:用户的姓氏。 name
可选:用户的全名。 picture
可选:用户的个人资料照片。
验证您的实现
您可以通过使用验证实现的OAuth 2.0游乐场工具。
在工具中,执行以下步骤:
- 单击配置 打开的OAuth 2.0配置窗口。
- 在OAuth流场中,选择客户端。
- 在OAuth端点字段中,选择自定义。
- 在相应字段中指定您的 OAuth 2.0 端点和您分配给 Google 的客户端 ID。
- 在步骤1部分,不要选择任何谷歌范围。相反,将此字段留空或键入对您的服务器有效的范围(如果不使用 OAuth 范围,则输入任意字符串)。当您完成后,单击授权的API。
- 在步骤2和步骤3段,完成OAuth 2.0流程和验证每个步骤按预期工作。
您可以通过验证您的实现谷歌帐户链接演示工具。
在工具中,执行以下步骤:
- 点击登录在与谷歌按钮。
- 选择您要关联的帐户。
- 输入服务标识。
- (可选)输入您将请求访问的一个或多个范围。
- 单击开始演示。
- 出现提示时,确认您可以同意并拒绝链接请求。
- 确认您被重定向到您的平台。