How can I verify a Google authentication API access token?

Question

How can I verify a Google authentication access token?

I need to somehow query Google and ask: Is [given access token] valid for the [exampl

Answer 1

For user check, just post get the access token as accessToken and post it and get the response

https://www.googleapis.com/oauth2/v1/tokeninfo?access_token=accessToken

you can try in address bar in browsers too, use httppost and response in java also

response will be like

{
     "issued_to": "xxxxxxxxxxxxx-xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx.apps.googleusercontent.com",
     "audience": "xxxxxxxxxxxxxxx-xxxxxxxxxxxxxxxxxxxxxxxxxx.apps.googleusercontent.com",
     "user_id": "xxxxxxxxxxxxxxxxxxxxxxx",
     "scope": "https://www.googleapis.com/auth/userinfo.profile https://gdata.youtube.com",
     "expires_in": 3340,
     "access_type": "offline"
    }

The scope is the given permission of the accessToken. you can check the scope ids in this link

Update: New API post as below

https://oauth2.googleapis.com/tokeninfo?id_token=XYZ123

Response will be as

 {
 // These six fields are included in all Google ID Tokens.
 "iss": "https://accounts.google.com",
 "sub": "110169484474386276334",
 "azp": "1008719970978-hb24n2dstb40o45d4feuo2ukqmcc6381.apps.googleusercontent.com",
 "aud": "1008719970978-hb24n2dstb40o45d4feuo2ukqmcc6381.apps.googleusercontent.com",
 "iat": "1433978353",
 "exp": "1433981953",

 // These seven fields are only included when the user has granted the "profile" and
 // "email" OAuth scopes to the application.
 "email": "testuser@gmail.com",
 "email_verified": "true",
 "name" : "Test User",
 "picture": "https://lh4.googleusercontent.com/-kYgzyAWpZzJ/ABCDEFGHI/AAAJKLMNOP/tIXL9Ir44LE/s99-c/photo.jpg",
 "given_name": "Test",
 "family_name": "User",
 "locale": "en"
}

For more info, https://developers.google.com/identity/sign-in/android/backend-auth