With the WSO2 API Manager 4.1.0 release, we introduce the new and improved Operation Level Policy Support Feature. This feature replaced the Message Mediation Feature we had in previous API Manager versions.

A policy is a collection of rules that will be executed at the API gateway. Using policies, we can make API invocations undergo slight behavioral modifications before reaching the backend. In a similar sense, we can modify the API response a client receives from the backend. These changes are governed by a set of policies that can be static or dynamic in nature and are enforced at the gateway level. This feature supports both of the API gateways of WSO2 API Manager, the regular gateway (Apache Synapse based), and Choreo Connect (Envoy proxy).

One major improvement over the previous Message Mediation Feature being the increased granularity of policy enforcement from API level to operation level. Each and every policy is easy to manage and could easily be reused. Once policies are attached to an API of choice, they are guaranteed to honor the execution order that the API creator intended.

With this feature, we introduce an all-new policy framework, we have introduced an interactive UI for policy implementation, enforcement, and governance.