I am making an ajax call from my client to the google oauth 2 API 'https://accounts.google.com/o/oauth2/auth?redirect_uri=http://blah.com&response_type=token&client_id....' to get the access token, but i get following error:
Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://blah-blah.com' is therefore not allowed access
I want the call to be ajax so that the user is not disturbed when the call is made through url or window.location.href or in other words, how can i get the access token such that the whole page does not load, and is it possible to resolve the above error???
OAuth2 auth endpoint doesn't support AJAX by design. It's an entry point to the authentication system, so you must get there by redirect. The result of the authentication is again a redirect to the URL you provide, so AJAX doesn't make much sense there.