Policy Languages

Policy languages provide a structured way to express authorization rules. They range from simple JSON configurations to sophisticated declarative languages with logical reasoning capabilities.

Key Characteristics

Declarative

Describe what is allowed, not how to check it. The engine figures out evaluation.

Composable

Build complex policies from simple rules. Combine, override, and extend as needed.

Testable

Write unit tests for policies. Verify behavior before deployment with test frameworks.

Interactive: Compare Policy Languages

Explore different policy languages and see how they express the same authorization logic:

Rego (OPA)

Declarative policy language for Open Policy Agent

package authz

# Allow if user is admin
allow {
  input.user.role == "admin"
}

# Allow if user owns resource
allow {
  input.user.id == input.resource.owner
}

Rego uses logical rules. Multiple allow rules are OR-ed together. If any rule evaluates to true, access is granted.

Choosing a Policy Language

Simple Needs

• JSON policies for basic rules
• Easy to generate programmatically
• No learning curve
• Limited expressiveness

Complex Requirements

• Rego or Cedar for rich logic
• Functions, conditions, variables
• Better testing and debugging
• Higher learning curve

💡

Best Practice

Start with the simplest language that meets your needs. You can always migrate to a more powerful language later. Consider team expertise, tooling support, and integration ecosystem when choosing. For AI agents, prefer languages with strong typing and validation to catch policy errors before runtime.

Policy Engines

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