OAuth और 'Google साइन-इन' के साथ बेहतर तरीके से लिंक करना

खास जानकारी

OAuth पर आधारित 'Google साइन-इन' को बेहतर तरीके से लिंक करने की सुविधा, Google साइन-इन को सबसे ऊपर जोड़ती है OAuth लिंकिंग. इससे Search Ads 360 के साथ-साथ Google उपयोगकर्ता हैं. यह खाता बनाने की सुविधा भी चालू करता है. इससे उपयोगकर्ता अपने Google खाते का इस्तेमाल करके, आपकी सेवा पर एक नया खाता बना सकते हैं.

OAuth और 'Google साइन-इन' की मदद से खाता लिंक करने के लिए, यहां दिए गए सामान्य निर्देशों का पालन करें चरण:

1. सबसे पहले, उपयोगकर्ता से Google पर अपनी प्रोफ़ाइल को ऐक्सेस करने की सहमति मांगें.
2. उनकी प्रोफ़ाइल में दी गई जानकारी का इस्तेमाल करके, पता लगाएं कि उपयोगकर्ता खाता मौजूद है या नहीं.
3. मौजूदा उपयोगकर्ताओं के लिए, खाते लिंक करें.
4. अगर आपको अपने पुष्टि करने वाले सिस्टम में, Google उपयोगकर्ता के लिए कोई मैच नहीं मिलता है, तो Google से मिले आईडी टोकन की पुष्टि करें. इसके बाद, एक उपयोगकर्ता के तौर पर आईडी टोकन में मौजूद प्रोफ़ाइल जानकारी पर.

पहली इमेज. आसान तरीके से लिंक करने की सुविधा की मदद से, उपयोगकर्ता के फ़ोन पर खाता लिंक करना

व्यवस्थित तरीके से लिंक करने के लिए ज़रूरी शर्तें

• वेब OAuth लिंकिंग का बेसिक फ़्लो लागू करें. आपकी सेवा में OAuth 2.0-अनुच्छेदनकर्ता का समर्थन करना आवश्यक है अनुमति और टोकन एक्सचेंज एंडपॉइंट.
• आपके टोकन एक्सचेंज एंडपॉइंट को JSON वेब टोकन (JWT) दावों के साथ काम करना चाहिए. साथ ही, यह check, create, और get इंटेंट लागू करना चाहिए.

• अपना Google API क्लाइंट आईडी रजिस्टर करें.

अपना OAuth सर्वर लागू करना

आपके टोकन एक्सचेंज के एंडपॉइंट को check, create, get इंटेंट के साथ काम करना चाहिए. यहां खाता लिंक करने के फ़्लो के दौरान पूरे किए गए चरण दिखाए गए हैं. साथ ही, यह भी बताया गया है कि अलग-अलग इंटेंट को कब कॉल किया जाता है:

1. क्या आपके पुष्टि करने वाले सिस्टम में उपयोगकर्ता का कोई खाता है? (हां या नहीं का विकल्प चुनकर, उपयोगकर्ता तय करता है)
   1. हां : क्या उपयोगकर्ता आपके प्लैटफ़ॉर्म में साइन इन करने के लिए, अपने Google खाते से जुड़े ईमेल पते का इस्तेमाल करता है? (हां या नहीं का विकल्प चुनकर, उपयोगकर्ता तय करता है)
      1. हां : क्या आपके पुष्टि करने वाले सिस्टम में उपयोगकर्ता का कोई खाता है? (पुष्टि करने के लिए check intent को कॉल किया गया है)
         1. हां : अगर इंटेंट वापस मिल जाता है, तो get intent को कॉल किया जाता है और खाता लिंक कर दिया जाता है.
         2. नहीं : नया खाता बनाएं? (हां या नहीं का विकल्प चुनकर, उपयोगकर्ता तय करता है)
            1. हां : create intent को कॉल किया जाता है और इंटेंट के वापस आने पर खाता लिंक कर दिया जाता है.
            2. नहीं : ऐसा करने पर, वेब OAuth फ़्लो ट्रिगर हो जाता है, उपयोगकर्ता को उसके ब्राउज़र पर भेजा जाता है, और उपयोगकर्ता को किसी दूसरे ईमेल से लिंक करने का विकल्प दिया जाता है.
      2. नहीं : ऐसा करने पर, वेब OAuth फ़्लो ट्रिगर हो जाता है. साथ ही, लोगों को उनके ब्राउज़र पर भेजा जाता है, और उपयोगकर्ता को किसी दूसरे ईमेल पते से लिंक करने का विकल्प दिया जाता है.
   2. नहीं : क्या आपके पुष्टि करने वाले सिस्टम में उपयोगकर्ता का कोई खाता है? (पुष्टि करने के लिए check intent को कॉल किया गया है)
      1. हां : अगर इंटेंट वापस मिल जाता है, तो get intent को कॉल किया जाता है और खाता लिंक कर दिया जाता है.
      2. नहीं : create intent को कॉल किया जाता है और इंटेंट के वापस आने पर खाता लिंक कर दिया जाता है.

Check for an existing user account (check intent)

After the user gives 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 responds with account_found=true. If the Google account doesn't match an existing user, your token exchange endpoint returns an HTTP 404 Not Found error with account_found=false.

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=check&assertion=JWT&scope=SCOPES&client_id=GOOGLE_CLIENT_ID&client_secret=GOOGLE_CLIENT_SECRET

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

To respond to the check intent requests, your token exchange endpoint must perform the following steps:

• Validate and decode the JWT assertion.
• Check if the Google account is already present in your authentication system.

Validate and decode the JWT assertion

You can validate and decode the JWT assertion by using a JWT-decoding library for your language. Use Google's public keys, available in JWK or PEM formats, to verify the token's signature.

When decoded, the JWT assertion looks like the following example:

{
  "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
  "email_verified": true,   // true, if Google has verified the email address
  "hd": "example.com",      // If present, the host domain of the user's GSuite email address
                            // If present, a URL to user's profile picture
  "picture": "https://lh3.googleusercontent.com/a-/AOh14GjlTnZKHAeb94A-FmEbwZv7uJD986VOF1mJGb2YYQ",
  "locale": "en_US"         // User's locale, from browser or phone settings
}

In addition to verifying the token's signature, verify that the assertion's issuer (iss field) is https://accounts.google.com, that the audience (aud field) is your assigned client ID, and that the token has not expired (exp field).

Using the email, email_verified and hd fields you can determine if Google hosts and is authoritative for an email address. In cases where Google is authoritative the user is currently known to be the legitimate account owner and you may skip password or other challenges methods. Otherwise, these methods can be used to verify the account prior to linking.

Cases where Google is authoritative:

• email has a @gmail.com suffix, this is a Gmail account.
• email_verified is true and hd is set, this is a G Suite account.

Users may register for Google Accounts without using Gmail or G Suite. When email does not contain a @gmail.com suffix and hd is absent Google is not authoritative and password or other challenge methods are recommended to verify the user. email_verified can also be true as Google initially verified the user when the Google account was created, however ownership of the third party email account may have since changed.

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. In that case, return a response like the following:

HTTP/1.1 200 Success
Content-Type: application/json;charset=UTF-8

{
  "account_found":"true",
}

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 needs to reply with a HTTP 404 error that specifies "account_found": "false", as in the following example:

HTTP/1.1 404 Not found
Content-Type: application/json;charset=UTF-8

{
  "account_found":"false",
}

Handle automatic linking (get intent)

After the user gives 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 linking_error error and optional login_hint.

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&scope=SCOPES&client_id=GOOGLE_CLIENT_ID&client_secret=GOOGLE_CLIENT_SECRET

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

To respond to the get intent requests, your token exchange endpoint must perform the following steps:

• Validate and decode the JWT assertion.
• Check if the Google account is already present in your authentication system.

Validate and decode the JWT assertion

You can validate and decode the JWT assertion by using a JWT-decoding library for your language. Use Google's public keys, available in JWK or PEM formats, to verify the token's signature.

When decoded, the JWT assertion looks like the following example:

{
  "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
  "email_verified": true,   // true, if Google has verified the email address
  "hd": "example.com",      // If present, the host domain of the user's GSuite email address
                            // If present, a URL to user's profile picture
  "picture": "https://lh3.googleusercontent.com/a-/AOh14GjlTnZKHAeb94A-FmEbwZv7uJD986VOF1mJGb2YYQ",
  "locale": "en_US"         // User's locale, from browser or phone settings
}

In addition to verifying the token's signature, verify that the assertion's issuer (iss field) is https://accounts.google.com, that the audience (aud field) is your assigned client ID, and that the token has not expired (exp field).

Using the email, email_verified and hd fields you can determine if Google hosts and is authoritative for an email address. In cases where Google is authoritative the user is currently known to be the legitimate account owner and you may skip password or other challenges methods. Otherwise, these methods can be used to verify the account prior to linking.

Cases where Google is authoritative:

• email has a @gmail.com suffix, this is a Gmail account.
• email_verified is true and hd is set, this is a G Suite account.

Users may register for Google Accounts without using Gmail or G Suite. When email does not contain a @gmail.com suffix and hd is absent Google is not authoritative and password or other challenge methods are recommended to verify the user. email_verified can also be true as Google initially verified the user when the Google account was created, however ownership of the third party email account may have since changed.

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 an account is found for the user, 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
}

In some cases, account linking based on ID token might fail for the user. If it does so for any reason, your token exchange endpoint needs to reply with a HTTP 401 error that specifies error=linking_error, as the following example shows:

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

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

When Google receives a 401 error response with linking_error, Google sends the user to your authorization endpoint with login_hint as a parameter. The user completes account linking using the OAuth linking flow in their browser.

Handle account creation via Google Sign-In (create intent)

When a user needs to create an account on your service, Google makes a request to your token exchange endpoint that specifies intent=create.

The request has the following form:

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&assertion=JWT&client_id=GOOGLE_CLIENT_ID&client_secret=GOOGLE_CLIENT_SECRET

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

The JWT within the assertion parameter contains 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 the create intent requests, your token exchange endpoint must perform the following steps:

• Validate and decode the JWT assertion.
• Validate user information and create new account.

Validate and decode the JWT assertion

You can validate and decode the JWT assertion by using a JWT-decoding library for your language. Use Google's public keys, available in JWK or PEM formats, to verify the token's signature.

When decoded, the JWT assertion looks like the following example:

{
  "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
  "email_verified": true,   // true, if Google has verified the email address
  "hd": "example.com",      // If present, the host domain of the user's GSuite email address
                            // If present, a URL to user's profile picture
  "picture": "https://lh3.googleusercontent.com/a-/AOh14GjlTnZKHAeb94A-FmEbwZv7uJD986VOF1mJGb2YYQ",
  "locale": "en_US"         // User's locale, from browser or phone settings
}

In addition to verifying the token's signature, verify that the assertion's issuer (iss field) is https://accounts.google.com, that the audience (aud field) is your assigned client ID, and that the token has not expired (exp field).

Using the email, email_verified and hd fields you can determine if Google hosts and is authoritative for an email address. In cases where Google is authoritative the user is currently known to be the legitimate account owner and you may skip password or other challenges methods. Otherwise, these methods can be used to verify the account prior to linking.

Cases where Google is authoritative:

• email has a @gmail.com suffix, this is a Gmail account.
• email_verified is true and hd is set, this is a G Suite account.

Users may register for Google Accounts without using Gmail or G Suite. When email does not contain a @gmail.com suffix and hd is absent Google is not authoritative and password or other challenge methods are recommended to verify the user. email_verified can also be true as Google initially verified the user when the Google account was created, however ownership of the third party email account may have since changed.

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. To do so, respond to the request with an HTTP 401 error that specifies error=linking_error and gives the user's email address as the login_hint. The following is a sample response:

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

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

When Google receives a 401 error response with linking_error, Google sends the user to your authorization endpoint with login_hint as a parameter. The user completes account linking using the OAuth linking flow in their browser.

If neither condition is true, create a new user account with the information provided in the JWT. New accounts don't typically have a password set. It's recommended that you add Google Sign-In to other platforms to enable users to log in with 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 to sign 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
}

अपना Google API क्लाइंट आईडी पाएं

खाता लिंक करने के रजिस्ट्रेशन की प्रक्रिया के दौरान, आपको अपना Google API क्लाइंट आईडी देना होगा.

OAuth लिंकिंग के चरणों को पूरा करते समय आपने जो प्रोजेक्ट बनाया था उसका इस्तेमाल करके, अपना एपीआई क्लाइंट आईडी पाने के लिए. इसके लिए, नीचे दिया गया तरीका अपनाएं:

1. अपना क्रेडेंशियल पेज खोलें Google API कंसोल.

2. Google API प्रोजेक्ट बनाएं या चुनें.

   अगर आपके प्रोजेक्ट में वेब ऐप्लिकेशन प्रकार के लिए क्लाइंट आईडी नहीं है, तो क्रेडेंशियल बनाएं > OAuth क्लाइंट आईडी बनाने के लिए. अपनी ऑडियंस की सूची में अनुमति वाले JavaScript ऑरिजिन बॉक्स में अपनी साइट के डोमेन के लिए. परफ़ॉर्मेंस स्थानीय टेस्ट या डेवलपमेंट के लिए, आपको http://localhost और अनुमति वाले JavaScript ऑरिजिन फ़ील्ड के लिए, http://localhost:<port_number>.

लागू करने की पुष्टि की जा रही है

You can validate your implementation by using the OAuth 2.0 Playground tool.

In the tool, do the following steps:

1. Click Configuration settings to open the OAuth 2.0 Configuration window.
2. In the OAuth flow field, select Client-side.
3. In the OAuth Endpoints field, select Custom.
4. Specify your OAuth 2.0 endpoint and the client ID you assigned to Google in the corresponding fields.
5. In the Step 1 section, don't select any Google scopes. Instead, leave this field blank or type a scope valid for your server (or an arbitrary string if you don't use OAuth scopes). When you're done, click Authorize APIs.
6. In the Step 2 and Step 3 sections, go through the OAuth 2.0 flow and verify that each step works as intended.

You can validate your implementation by using the Google Account Linking Demo tool.

In the tool, do the following steps:

1. Click the Sign-in with Google button.
2. Choose the account you'd like to link.
3. Enter the service ID.
4. Optionally enter one or more scopes that you will request access for.
5. Click Start Demo.
6. When prompted, confirm that you may consent and deny the linking request.
7. Confirm that you are redirected to your platform.