This is an example on how to authenticate with spring security sans the annoying templates
I spent more time than I would like to admit trying to figure out how to do this. Most examples for spring security rely on some template engine with a form login. For what I wanted, I just needed a simple endpoint for an ajax call to be made and then setup a session. This is an example of the simplest way I found to achieve this.
From here I can implement a DaoAuthenticationProvider or similar to authenticate against another microservice.
I need to spend some more time and add the ability to post a JSON object for auth.