Require Google to return email address as part of OAuth

I am using OAuth to access Gmail with dotNetOAuth. How can I force Google to return user's email address as part of callback after authorization?

By default, Google OAuth callback only returns the 开发者_StackOverflow中文版token secret and access tokens.

First you need to add the following scope (https://www.googleapis.com/auth/userinfo.email) to your oauth request.

After you're back to your app from Google and you have your access token, you can make a request using the access token to https://www.googleapis.com/userinfo/email?alt=json. This will return the email address. More info at http://sites.google.com/site/oauthgoog/Home/emaildisplayscope

For getting the Email Id, you need to add the scope "https://wwww.googleapis.com/auth/userinfo.email"

Then you will get id_token in the response.

Response={
   "access_token" : "ya29.eAG__HY8KahJZN9VmangoliaV-Jn7hLtestkeys",
   "token_type" : "Bearer",
   "expires_in" : 3600,
   "id_token" : "id_token_from_server",
   "refresh_token" : "1/GIHTAdMo6zLVKCqNbA"
 }

Then use this id_token as below POST request:

https://www.googleapis.com/oauth2/v1/tokeninfo?id_token=id_token_from_server

And you will get response like below:

Response={
 "issuer": "accounts.google.com",
 "issued_to": "80780.apps.googleusercontent.com",
 "audience": "8078909.apps.googleusercontent.com",
 "user_id": "1118976557884",
 "expires_in": 3598,
 "issued_at": 1456353,
 "email": "emailId@gmail.com",
 "email_verified": true
}

Make sure you add "www" in the APIs as shown above...

OAuth doesn't provide a facility for extra parameters during an OAuth handshake, so I don't think you can force Google to supply it. There is likely a Google API however that you can use your OAuth access token to call to fetch the email address after the handshake, however.

request OAuth scope to include the "Email Display Scope" https://www.googleapis.com/auth/userinfo.email

scope="http://www.google.com/m8/feeds/ https://www.googleapis.com/auth/userinfo.email"

Then use REST API like Hammock to get address

            RestClient client = new RestClient
            {
                Authority = "https://www.googleapis.com",
            };

            RestRequest request = new RestRequest
            {
                Path = "userinfo/email?alt=json",
                Credentials = OAuthCredentials.ForProtectedResource(
                     this.requestSettings.ConsumerKey,
                     this.requestSettings.ConsumerSecret,
                     this.requestSettings.Token,
                     this.requestSettings.TokenSecret)
            };

            var response = client.Request(request);

Here's a c# function for when you have pre-authorized the request as detailed above:

        private void FetchUsersEmail(token)
        {
            var emailRequest = @"https://www.googleapis.com/userinfo/email?alt=json&access_token=" + token;
            // Create a request for the URL.        
            var request = WebRequest.Create(emailRequest);
            // Get the response.
            var response = (HttpWebResponse) request.GetResponse();
            // Get the stream containing content returned by the server.
            var dataStream = response.GetResponseStream();
            // Open the stream using a StreamReader for easy access.
            var reader = new StreamReader(dataStream);
            // Read the content. 
            var jsonString = reader.ReadToEnd();
            // Cleanup the streams and the response.
            reader.Close();
            dataStream.Close();
            response.Close();

            dynamic json = JValue.Parse(jsonString);
            var currentGoogleEmail = json.data.email;
        }

(JValue is part of JSON.Net)

In php, apiOauth2Service.php class provides methods to access logged in user info. For this you can use userinfo->get() method. Make sure you also use scope https://www.googleapis.com/auth/userinfo.email.

This will work with same access token. Also you should try looking in other APIs for similar kind of information in return. This is much easier to look through oAuth_playground >> http://code.google.com/apis/explorer/

If you request the userinfo.email scope, Google returns an id_token along with the access_token.

The id_token can be unencrypted to provide the user's email address, at www.googleapis.com?/oauth2/v1/tokeninfo?id_token=IDTOKENHERE

More information here: https://developers.google.com/accounts/docs/OAuth2Login