DataTerminology.comNEW
Also known as: OPA
An open-source, general-purpose policy engine that unifies and enforces policies across cloud-native systems.
DESCRIPTION
Open Policy Agent (OPA) decouples policy from application code using the Rego language and a declarative decision API. It evaluates policies for authorization, admission control, data filtering, and compliance across microservices, Kubernetes, CI/CD, and APIs. OPA embeds as a sidecar or runs as a service, supporting JSON inputs, partial evaluation, and fine-grained decisions. Gatekeeper integrates OPA for Kubernetes admission controls. Its portability and ecosystem make it a foundational component for policy as code.
ALTERNATIVE DEFINITIONS
Open Policy Agent
OPA is an open source, general-purpose policy engine that unifies policy enforcement across the stack.
Highlights cross-stack, unified enforcement and open-source positioning.
Cloud Native Computing Foundation
Open Policy Agent (OPA) is a policy engine for cloud-native environments that enables unified, context-aware policy enforcement.
Frames OPA within the CNCF ecosystem and cloud-native context.
Open Policy Agent (GitHub)
OPA is a general-purpose policy engine that provides fine-grained, context-aware policy decisions via a declarative language (Rego).
Emphasizes declarative policies and fine-grained decisioning.
RELATED TERMS
Rego Gatekeeper Governance as Code RBAC IAM JSON
COMPETING TERMS
Kyverno Kubernetes Admission Controllers
RELATIONS
- Broader: Agent
KNOWLEDGE AREAS
Data Security Data Governance Software Engineering Cloud
TARGET AUDIENCE
DevOps Engineer Cloud Architect Data Governance Manager Chief Information Officer Software Developer
EXTERNAL SOURCES
- Wikipedia - Open Policy Agent
- Open Policy Agent - Official OPA documentation
- Gatekeeper - OPA-based Kubernetes admission controller
- Kubernetes - Admission controllers overview
- Styra Academy - Training for OPA and Rego
TOP QUESTIONS
Why use Open Policy Agent over hardcoded authorization?
OPA centralizes policies, reduces code duplication, and enables consistent decisions across services. It accelerates audits and compliance with clear, testable rules.
Category: Opinion
How does OPA integrate with Kubernetes?
OPA integrates via Gatekeeper for admission controls, evaluating Rego constraints on resource creation and updates before they’re persisted.
Category: Application
What is Rego in the context of OPA?
Rego is OPA’s declarative policy language for expressing constraints and decisions over structured data inputs such as JSON.
Category: Overview
What are common mistakes when adopting OPA?
Writing overly complex policies, skipping unit tests, and not designing clear data inputs hinder maintainability and correctness.
Category: Mistakes
What risks should be considered with Open Policy Agent?
Performance overhead from complex policies and misconfigured caching can cause latency. Incorrect policies may block critical operations.
Category: Risks
How do you manage OPA policies at scale?
Use version control, CI for policy tests, bundles for distribution, and observability for decision logs and metrics.
Category: Management
What alternatives compete with Open Policy Agent?
Kyverno for Kubernetes-native policies and custom admission controllers are common alternatives, especially in Kubernetes-centric environments.
Category: Alternatives
How does OPA support compliance and audits?
OPA provides decision logs, testable policies, and centralized governance enabling traceability and evidence for audits.
Category: Requirements
Where to start learning Open Policy Agent?
Study OPA docs, practice small Rego policies, then integrate Gatekeeper in a non-production cluster to validate constraints.
Category: Learning