opa

Open Policy Agent (OPA) is an open-source, general-purpose policy engine that enables unified, context-aware policy enforcement across the entire stack. It is a graduated project in the Cloud Native Computing Foundation (CNCF). OPA allows you to define rules (policies) using a high-level declarative language called Rego. These rules govern system behavior, answering questions like authorization (can user X call operation Y on resource Z?), deployment placement, or resource requirements. Services integrate with OPA by executing queries when policy decisions are needed; OPA evaluates the rules and data to produce an answer, which the service then enforces. Key features and capabilities: - **Rego language**: A declarative policy language for authoring rules. - **Integration options**: High-level Go SDK, low-level Go API, REST API for other languages, and integration with systems like Kubernetes, Terraform, Docker, and SSH. - **Tooling**: Rego Playground for writing and sharing policies, VS Code extension for local development with diagnostics and debugging. - **Deployment**: Available as CLI, Docker images, and binaries via GitHub releases. - **Ecosystem**: Community projects listed in an ecosystem directory, production adopters listed in ADOPTERS.md. - **Community**: Slack channel, community discussions, and commercial support options. OPA is used for policy enforcement in cloud-native environments, enabling decoupling of policy decisions from service code. It supports use cases like API authorization, Kubernetes admission control, and infrastructure policy compliance.