title: Spring cloud authentication service
body: <p>I am trying to develop a system containing microservices. Generally my goal is to have:
  1. Some front-end application,
  2. Spring cloud gateway,
  3. Auth service
  4. Resource services</p>
  
  <p>What i'd like gw to do is:
  1. Validate token every request,
  2. Prevent unauthenticated calls to our services.</p>
  
  <p>What i'd like auth-service to do is:
  1. Validate user credentials,
  2. Return token is succeded</p>
  
  <p>I have developed a gw instance, with Filter extending AbstractNameValueGatewayFilterFactory what therefore i apply for routes that should be secured.</p>
  
  <p>I have no idea how to implement authentication-service, somehow can't go through security in webflux together with spring cloud. Eventually i want to have something simmilar to:
  <a href="https://medium.com/omarelgabrys-blog/microservices-with-spring-boot-authentication-with-jwt-part-3-fafc9d7187e8" rel="nofollow noreferrer">https://medium.com/omarelgabrys-blog/microservices-with-spring-boot-authentication-with-jwt-part-3-fafc9d7187e8</a> , but written in reactive approach. Has anyone seen good example for that? Or maybe u know how to do it? </p>