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Version: 1.18

Introduction to Open Policy Agent

note

Open Policy Agent support has been introduced starting from these releases:

  • kwctl: v0.2.0
  • policy-server: v0.2.0

Open Policy Agent (OPA) is a general purpose policy framework that uses the Rego language to write policies.

Introduction​

Rego policies work by receiving an input to evaluate, and produce an output as a response. In this sense, OPA has no specific tooling for targeting writing policies for Kubernetes.

Specifically, policies in OPA receive a JSON input and produce a JSON output. The OPA server is configured to receive admission review requests from Kubernetes. The policies receive a Kubernetes AdmissionReview object in JSON format. They have to return a valid AdmissionReview object as the evaluation results.

Compatibility with existing policies​

All policies can be compiled to the wasm target (WebAssembly) with the official opa CLI tool.

In terms of policy execution, you can read more about the OPA built-in support implemented in Kubewarden.