title: Flutter: way to validate one sort of google account?
body: <p>I'm building an app in flutter (latest build) for students on the university. every student has its own email and password (ex. s2170456@student.utwente.nl), which is integrated in google, so everyone is able to see notifications in Gmail.</p>
  
  <p>This does also mean; if you want to log in with google, your studentEmail is an option to do so. I want to implement a google log-in feature where only student of the university (with their email sXXXXXXX@student.utwente.nl) are able to login. </p>
  
  <p>My question is: is there a way to filter on the google login email? I thought about using normal email login and use RegEx to validate, but this means student should firstly signup. I would like to skip the whole sign-up and let the students use their already owned student email to signin. </p>
  
  <p>it should look something like this (if it is even possible) VV</p>
  
  <pre><code>Widget googleLogin () {
  googleLogin button()
  if(googlelogin.email == sXXXXXXX@student.utwente.nl)
      log user in;
  } else {
      return error message('invalid email')
  }
  </code></pre>
  
  <p>I want this to be able to only register and login user with student email.</p>