If you cancel it, it will throw "Internal Server Error" EDIT : http://www.branchtip.com/oauth2callback?error=user_cancelled_authorize&error_description=The+use

If you cancel it, it will throw "Internal Server Error" EDIT : http://www.branchtip.com/oauth2callback?error=user_cancelled_authorize&error_description=The+user+cancelled+the+authorization&state=987654321 http://www.branchtip.com/oauth2callback?error=user_cancelled... I think here else case is missing. Another thing IF you mimic actual url param 'http://www.branchtip.com/oauth2callback?code=' http://www.branchtip.com/oauth2callback?code=' it will show ``code length = 0`` ^ Might be log.