Preventing automatic sign-in when using Google+ Si

2019-01-08 11:48发布

问题:

I am in the process of integrating Google+ sign in with my site, which also lets users sign in with Twitter and Facebook. The sign in page of the site therefore has 3 buttons, one for each of the services.

The issue I am having is in the following scenario:

  • user goes to the sign in page
  • user signs in successfully with G+
  • user signs out of my site (but the account is still associated with G+, signing out of the site does not disconnect the G+ account)
  • user visits the sign in page again
  • at this stage the Sign in with G+ button is rendered and automatically signs the user into the account associated with G+ without the user having to click the button

The problem is that on revisiting the sign in page, I want the user to have the option of signing in with another service, rather than automatically being signed in with G+. If the user wants to sign in with G+ then they can do so by clicking the button - the user will then be signed in automatically.

Is it possible to prevent this automatic sign in on button render? I can simulate it by using the data-approvalprompt="force" as an attribute on the button, but I don't think this is an ideal solution (the user then has to go through the confirmation process, which I would ideally would like to prevent)

回答1:

Update

The best supported way to prevent automatic sign-in is to use the API method gapi.auth2.getAuthInstance().signOut() which will prevent automatic sign-in on your site after it has been called. Demo here.

In the demo, the user is signed out when they leave the page as shown in the following code:

window.onbeforeunload = function(e){
  gapi.auth2.getAuthInstance().signOut();
};

Now, whenever the user exits the site (e.g. closes the window, navigates away), they will be signed out and the sign in button will not trigger sign-in until the user clicks it.

I don't recommend you do this in your own implementation but instead allow the user to explicitly sign out when they no longer desire want to be signed in. Also, please note that my example is a demo, you probably do not want to sign the user out automatically any time they leave your site.

Original Post

First, you should not be using data-approvalprompt="force" as this will cause extra authorized subtokens to be issued to your application / client and is designed to be used in scenarios where the user needs to be reauthorized after credentials have been lost server-side.

Second, you probably do not want to have the behavior where the user needs to click to sign in because they are already "signed in" to their Google account and it could be confusing to need to sign in (or trigger sign-in) again, separately, for your site.

If you really wanted to do this, you would perform an explicit render for the signin button but would not make the call to gapi.signin.render as documented in the Google+ sign-in documentation until you are aware that the user will not automatically get signed in.

The following code shows how to enable explicit render of the sign-in button:

<script type="text/javascript" src="https://apis.google.com/js/plusone.js">
{"parsetags": "explicit"}
</script>
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>
<head>
<script type="text/javascript">
var token = "";
function onSigninCallbackVanilla(authResponse){
   // in a typical flow, you show disconnect here and hide the sign-in button
}

The following code shows you how to explicitly render the button:

  <span id="signinButton">
    <button id = "shim" onclick="gapi.signin.go(); $('#shim').hide();">Show the button</button>
    <span
      class="g-signin"
      data-callback="onSigninCallbackVanilla"
      data-clientid="YOUR_CLIENT_ID"
      data-cookiepolicy="single_host_origin"
      data-requestvisibleactions="http://schemas.google.com/AddActivity"
      data-scope="https://www.googleapis.com/auth/plus.login">

    </span>
  </span>  

How you're communicating that the user is signed out of your site is probably going to vary from site to site, but one approach could be to set a cookie indicating the "signed out" state for a user and then using this as the trigger for blocking explicit load. The behavior gets a little trickier when a user visits your site and has disabled cookies or uses a separate, signed-in, browser. To address this, you could do something complicated like querying the user state from your server over XHR on the sign-in callback and pretending not to know the user is signed in to Google+.



回答2:

Just check for g-auth-window in the callback function:

    function google_sign_callback(authResult){
        if(authResult['g-oauth-window']){

        }else if(authResult['error']) {

        }
    }


回答3:

I had this issue and used auth2.disconnect()

function onSignIn(googleUser) {
    var profile = googleUser.getBasicProfile();
    var auth2 = gapi.auth2.getAuthInstance();
    auth2.disconnect();

    //do other stuff
}

Edit: you need to store the token before you disconnect because in some cases id_token will become null after disconnect:

function onSignIn(googleUser) {
    var profile = googleUser.getBasicProfile();
    var idToken=profile.id_token;
    googleUser.disconnect()

    //use idToken for server side verification
}

If i'm correct you have your own sign in mechanism for your site and just need google sign in to sign up a user on verified email. in this case you can easily disconnect after you get the profile info. Next time you load the page you will see "sign in" button instead of "signed in " button.



回答4:

Unfortunately calling gapi.auth.signOut() made the app to log-in again when I'm requesting user data (neither it is persistent)

So the solution, as suggested by @class is to revoke the token:

  $.ajax({
    type: 'GET',
    url: 'https://accounts.google.com/o/oauth2/revoke?token=' +
        gapi.auth.getToken().access_token,
    async: false,
    contentType: 'application/json',
    dataType: 'jsonp',
    success: function(result) {
      console.log('revoke response: ' + result);
      $('#authOps').hide();
      $('#profile').empty();
      $('#visiblePeople').empty();
      $('#authResult').empty();
      $('#gConnect').show();
    },
    error: function(e) {
      console.log(e);
    }
  });


回答5:

I too has same issue this how i fixed it.I may not sure this is a stander way to do it but still it works fine with me...

add this Google JS from google developer

<script src="https://apis.google.com/js/platform.js" async defer></script>
<script>

function onSuccessG(googleUser) {
        var profile = googleUser.getBasicProfile();
        console.log('ID: ' + profile.getId()); // Do not send to your backend! Use an ID token instead.
        console.log('Name: ' + profile.getName());
        console.log('Image URL: ' + profile.getImageUrl());
        console.log('Email: ' + profile.getEmail());
}
function onFailureG(error) {
    console.log(error);
}
function renderGmail() {

  gapi.signin2.render('my-signin2', {
    'scope': 'https://www.googleapis.com/auth/plus.login',
    'width': 0,
    'height': 0,
    'longtitle': true,
    'theme': 'dark',
    'onsuccess': onSuccessG,
    'onfailure': onFailureG
  });
}

Now add html link and onClick call this renderGmail() function.

<a href="javascript:void(0)" onclick="renderGmail();"> SignUp with Gmail</a>

I hope this works...



回答6:

I am using https://developers.google.com/identity/sign-in/web/build-button to build the sign in button for my web app which gives the user a choice to log in through either Facebook or Google. This code is pretty easy for obtaining the Id_token. However it also came with automatic signing in of the user if the user is already signed in.

Thus, adding the following snippet in the beginning of the script helped me control the signup procedure.

    window.onbeforeunload = function(e){
      gapi.auth2.getAuthInstance().signOut();
    };

Thanks!



回答7:

Our AngularJS solution was:

$scope.$on('event:google-plus-signin-success', function (event, authResult) {
                if( authResult.status.method !== "AUTO"){
                    onGoogleLogIn(authResult[settings.configKeys.googleResponseToken]);
                }
            });


回答8:

I have been struggling with this for a while and could not find a way to prevent automatic sign in to Google using the "easy implementation" of the Sign-in

I ended up using the custom integration which does not attempt to auto sign in (also allowed me to change the appearance in the same time)



回答9:

I solved this by adding a click handler to my Google sign-in button. The click handler sets a global Javascript variable google_sign_in to true. When the onSuccess() handler fires (whether automatically on page load, or manually when the user clicks the sign-in button), it first checks whether google_sign_in == true and only then does it continue signing the user in:

<div id="google-signin2" onclick="return do_click_google_signin();"></div>

<script>
    var google_sign_in = false; // assume

    function do_click_google_signin() {
        google_sign_in = true;
    }

    function onSuccess( googleUser ) {
        if ( google_sign_in ) {
            // Process sign-in
        }
    }

    // Other redundant login stuff not shown...
</script>


标签: google-plus