UPDATE2: I revisited this issue and have solved the problem by carefully following the doco linked below. But first, for those who are struggling with this, you are in good company. There are so many versions of the doco from Google it is confusing! Do you include platform.js or client.js in your html? Do you load gapi.auth or gapi.auth2? Do you use gapi.auth2.render or gapi.auth.authorize, or gapi.auth2.init, and so on.
The way that returns an access_token (as of this article date) is linked below. I managed to get this working by carefully following the guide and reference using platform.js. Other libraries are then dynamically loaded such as client.js using gapi.load('drive', callback).
https://developers.google.com/identity/sign-in/web/listeners https://developers.google.com/identity/sign-in/web/reference
==== ORIGINAL ISSUE FOR PROSPERITY ====
UPDATE 1: I've updated the code sample to do a recursive search of the googleUser object. At least this shouldn't break in a subsequent library.
Below is a code snippet to handle an issue where the access_token in the Google gapi.auth2.AuthResponse object is not at the top level... it is hidden :( in the depths of the object!
So it is retrievable, but not at the top level!!?? I've noticed it seems to be a timing issue... once the application is running for a while on subsequent checks, it does contain the access token at the top level!!
var authResponse = _.googleUser.getAuthResponse();
_.id_token = authResponse.id_token; // Always exists
// access_token should also be a param of authResponse
if (authResponse.access_token) {
debug("Worked this time?");
_.access_token = authResponse.access_token;
} else {
// !!! Internal object access !!!
debug("Attempt to get access token from base object.");
_.access_token = _.objRecursiveSearch("access_token", _.googleUser);
if (_.access_token) {
debug("Access token wasn't on authResponse but was on the base object, WTF?");
} else {
debug("Unable to retrieve access token.");
return false;
}
}
_.objRecursiveSearch = function(_for, _in) {
var r;
for (var p in _in) {
if (p === _for) {
return _in[p];
}
if (typeof _in[p] === 'object') {
if ((r = _.objRecursiveSearch(_for, _in[p])) !== null) {
return r;
}
}
}
return null;
}
I'm guessing getAuthResponse somehow provides a callback once it is ready, but I can't see where in the API. https://developers.google.com/identity/sign-in/web/reference