In this chapter, we have seen how Spring Cloud Gateway can be used as an edge server to control what services are allowed to be called from the outside of the system landscape. Based on predicates, filters, and destination URIs, we can define routing rules in a very flexible way. If we want to, we can configure Spring Cloud Gateway to use a discovery service such as Netflix Eureka to look up the target microservice instances.
One important question still unanswered is how we prevent unauthorized access to the APIs exposed by the edge server and how we can prevent third parties from intercepting the traffic.
In the next chapter, we will see how we can secure access to the edge server using standard security mechanisms such as HTTPS, OAuth, and OpenID Connect.
