通过 OAuth 和 Google 登录 (Dialogflow) 实现帐号关联

OAuth 和 Google 登录关联类型会在基于 OAuth 的基础上添加 Google 登录 账号关联。这样可以为 Google 用户提供基于语音的无缝链接 还可以为注册您服务的用户启用账号关联 使用非 Google 身份创建。

这种关联类型从 Google 登录开始，这样您就可以查看用户是否 您的系统中已存在 Google 个人资料信息。如果用户的信息 ，则开始标准 OAuth 流程。用户还可以 选择用其 Google 个人资料信息创建一个新账号。

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如需通过 OAuth 和 Google 登录机制执行账号关联，请遵循以下常规 步骤：

1. 首先，请用户同意访问其 Google 个人资料。
2. 使用用户个人资料中的信息来识别用户。
3. 如果您在身份验证系统中找不到与 Google 用户匹配的信息， 流程是否继续取决于您是否配置了 Actions 项目 在 Actions 控制台中，允许用户通过语音创建用户账号，或仅允许 。
   • 如果您允许通过语音创建账号，请验证身份证件 从 Google 收到的令牌。然后，您可以根据 个人资料信息。
   • 如果您不允许通过语音创建账号，则系统会将用户转到 一个浏览器，他们可以加载您的授权页面， 创建流程

支持通过语音创建账号

如果您允许通过语音创建用户账号，Google 助理会询问用户 他们希望执行以下操作：

• 使用对方的 Google 账号信息在您的系统上创建新账号，或者
• 使用已有其他账号登录您的身份验证系统 现有的非 Google 账号。

如果您希望尽量减少 账号创建流程中的障碍用户只需退出语音流 可以使用现有的非 Google 账号登录。

禁止通过语音创建账号

如果你禁止通过语音创建用户账号，Google 助理会打开 您为用户身份验证而提供的网站。如果互动发生 在没有屏幕的设备上，Google 助理会将用户转到手机 以继续进行账号关联流程。

在以下情况下，建议禁止创建：

• 您不希望允许拥有非 Google 账号的用户创建新的 用户账号，并希望将用户与您账号中的 身份验证系统。例如，如果您提供会员回馈活动， 可能需要确保用户不会丢失其 现有账号

• 您需要完全控制账号创建流程。例如，你可以 禁止创建（如果您需要向用户显示服务条款） 创建账号。

实现 OAuth 和 Google 登录账号关联

账号已与业界标准的 OAuth 2.0 流程相关联。 Actions on Google 支持隐式和授权代码流程。

在隐式代码流程中，Google 会在用户浏览器中打开您的授权端点。成功登录后，系统会向 Google 返回长期访问令牌。现在，从 Google 助理向你的 Action 发送的每个请求中都包含此访问令牌。

在授权代码流程中，您需要两个端点：

• 授权端点，该端点负责向尚未登录的用户显示登录界面，并以短期授权代码的形式记录所请求的访问。
• 令牌交换端点，负责两种类型的交换：
  1. 将授权代码交换为长期刷新令牌和短期访问令牌。用户完成帐号关联流程后，系统会进行这种交换。
  2. 将长期刷新令牌换成短期访问令牌。Google 需要新访问令牌时，由于此令牌已过期，因此会进行此交换。

虽然隐式代码流程的实现更简单，但 Google 建议通过隐式流程发出的访问令牌永远不会过期，因为将令牌过期与隐式流程一起使用会强制用户再次关联其帐号。如果出于安全考虑需要令牌到期，强烈建议您考虑使用身份验证代码流程。

配置项目

将项目配置为使用 OAuth 和 Google 登录账号 请按照以下步骤进行操作：

1. 打开 Actions 控制台，然后选择要使用的项目。
2. 点击开发标签页，然后选择账号关联。
3. 启用账号关联旁边的开关。
4. 在“账号创建”部分，选择是。

5. 在关联类型中，选择 OAuth & OAuth &Google 登录和隐式。

   

6. 在客户端信息中，执行以下操作：

   • 为 Actions to Google 颁发的客户端 ID 指定一个值，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。

7. 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 OAuth2 implicit 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&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.

Handle automatic linking

After the user gives your Action consent to access their Google profile, Google sends a request that contains a signed assertion of the Google user's identity. The assertion contains information that includes the user's Google Account ID, name, and email address. The token exchange endpoint configured for your project handles that request.

If the corresponding Google account is already present in your authentication system, your token exchange endpoint returns a token for the user. If the Google account doesn't match an existing user, your token exchange endpoint returns a user_not_found error.

The request has the following form:

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

grant_type=urn:ietf:params:oauth:grant-type:jwt-bearer&intent=get&assertion=JWT&consent_code=CONSENT_CODE&scope=SCOPES

Your token exchange endpoint must be able to handle the following parameters:

When your token exchange endpoint receives the linking request, it should do the following:

验证和解码 JWT 断言

您可以使用适用于您语言的 JWT 解码库来验证和解码 JWT 断言。 使用 Google 的公钥（适用于 JWK 或 PEM 格式）来验证令牌的 签名。

解码后，JWT 断言如以下示例所示：

{
  "sub": 1234567890,        // The unique ID of the user's Google Account
  "iss": "https://accounts.google.com",        // The assertion's issuer
  "aud": "123-abc.apps.googleusercontent.com", // Your server's client ID
  "iat": 233366400,         // Unix timestamp of the assertion's creation time
  "exp": 233370000,         // Unix timestamp of the assertion's expiration time
  "name": "Jan Jansen",
  "given_name": "Jan",
  "family_name": "Jansen",
  "email": "jan@gmail.com", // If present, the user's email address
  "locale": "en_US"
}

除了验证令牌的签名之外，还要验证断言的颁发者 （iss 字段）为 https://accounts.google.com，且受众群体（aud 字段） 是分配给您的 Action 的客户端 ID。

Check if the Google account is already present in your authentication system

Check whether either of the following conditions are true:

• The Google Account ID, found in the assertion's sub field, is in your user database.
• The email address in the assertion matches a user in your user database.

If either condition is true, the user has already signed up and you can issue an access token.

If neither the Google Account ID nor the email address specified in the assertion matches a user in your database, the user hasn't signed up yet. In this case, your token exchange endpoint should reply with a HTTP 401 error, that specifies error=user_not_found, as in the following example:

HTTP/1.1 401 Unauthorized
Content-Type: application/json;charset=UTF-8

{
  "error":"user_not_found",
}

Handle account creation via Google Sign-In

When a user needs to create an account on your service, Google makes a request to your token exchange endpoint that specifies intent=create, as in the following example:

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

response_type=token&grant_type=urn:ietf:params:oauth:grant-type:jwt-bearer&scope=SCOPES&intent=create&consent_code=CONSENT_CODE&assertion=JWT[&NEW_ACCOUNT_INFO]

The assertion parameter contains A JSON Web Token (JWT) that provides a signed assertion of the Google user's identity. The JWT contains information that includes the user's Google Account ID, name, and email address, which you can use to create a new account on your service.

To respond to account creation requests, your token exchange endpoint must do the following:

验证和解码 JWT 断言

您可以使用适用于您语言的 JWT 解码库来验证和解码 JWT 断言。 使用 Google 的公钥（适用于 JWK 或 PEM 格式）来验证令牌的 签名。

解码后，JWT 断言如以下示例所示：

{
  "sub": 1234567890,        // The unique ID of the user's Google Account
  "iss": "https://accounts.google.com",        // The assertion's issuer
  "aud": "123-abc.apps.googleusercontent.com", // Your server's client ID
  "iat": 233366400,         // Unix timestamp of the assertion's creation time
  "exp": 233370000,         // Unix timestamp of the assertion's expiration time
  "name": "Jan Jansen",
  "given_name": "Jan",
  "family_name": "Jansen",
  "email": "jan@gmail.com", // If present, the user's email address
  "locale": "en_US"
}

除了验证令牌的签名之外，还要验证断言的颁发者 （iss 字段）为 https://accounts.google.com，且受众群体（aud 字段） 是分配给您的 Action 的客户端 ID。

Validate user information and create new account

Check whether either of the following conditions are true:

• The Google Account ID, found in the assertion's sub field, is in your user database.
• The email address in the assertion matches a user in your user database.

If either condition is true, prompt the user to link their existing account with their Google Account by responding to the request with an HTTP 401 error, specifying error=linking_error and the user's email address as the login_hint, as in the following example:

HTTP/1.1 401 Unauthorized
Content-Type: application/json;charset=UTF-8

{
  "error":"linking_error",
  "login_hint":"foo@bar.com"
}

If neither condition is true, create a new user account using the information provided in the JWT. New accounts do not typically have a password set. It is recommended that you add Google Sign In to other platforms to enable users to log in via Google across the surfaces of your application. Alternatively, you can email the user a link that starts your password recovery flow to allow the user to set a password for signing in on other platforms.

When the creation is completed, issue an access token and return the values in a JSON object in the body of your HTTPS response, like in the following example:

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

启动身份验证流程

使用账号登录帮助程序 intent 启动身份验证流程。

const app = dialogflow({
  // REPLACE THE PLACEHOLDER WITH THE CLIENT_ID OF YOUR ACTIONS PROJECT
  clientId: CLIENT_ID,
})

// Intent that starts the account linking flow.
app.intent('Start Signin', conv => {
  conv.ask(new SignIn('To get your account details'))
})

private String clientId = "<your_client_id>";

@ForIntent("Start Signin")
public ActionResponse text(ActionRequest request) {
  ResponseBuilder rb = getResponseBuilder(request);
  return rb.add(new SignIn().setContext("To get your account details")).build();
}

const app = actionssdk({
  clientId: CLIENT_ID,
})

app.intent('Start Signin', conv => {
  conv.ask(new SignIn('To get your account details'))
})

private String clientId = "<your_client_id>";

@ForIntent("actions.intent.TEXT")
public ActionResponse text(ActionRequest request) {
  ResponseBuilder rb = getResponseBuilder(request);
  return rb.add(new SignIn().setContext("To get your account details")).build();
}

处理数据访问请求

如果 Google 助理请求包含访问令牌， 首先检查访问令牌是否有效且未过期，然后从 用户账号数据库 与令牌关联的用户账号。