I am using closure library to do a simple POST. I think XhrIo should work because from my machine when I use any other rest client ,like Firefox browser app RESTClient or Ch
If you are pass Content-Type on authorization request it will convert POST method to OPTIONS method so while we are use ouath and passing authorization token that time do not required Content-Type.
So do not passContent-Type on all authorization request it won't change your method POST to OPTIONS