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The Library in Reva provides a centralized space to create, manage, and reuse core building blocks of access control Policy, Schema, and Entity Type. It is designed to help teams enforce standardized, compliant, and scalable authorization across applications and environments.

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Pre-requisites

Before working with the Library, ensure the following:
  1. Schema Definition is Mandatory You must create a Schema before defining any policies. Schemas define the structure of the entities (User, Resource, Action, Context) and their attributes, which are referenced during policy evaluation.
  2. Entity Type Understand the attributes and context data used in your policies. Examples:
    • User: role, token.amr, justification
    • Resource: sensitivity, type, environment, creation_date
    • Context: time, datetime, ip_address
Policies in the Library cannot be created without a Schema. The Schema acts as the structural foundation required for policy definition, validation, and evaluation.

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Components in the Library

  1. Entity Type
    Entity Types define the actual objects referenced in policies (e.g., User, Resource, Action). Each includes attributes and contextual values used for condition evaluation.
    EntityAttributes UsedContext Used
    Userroletoken.amr, justification
    Resourcesensitivity, environment, api_endpoint, type, creation_datetime, datetime
    These Entity Types are foundation to policies involving role-based access, data protection, MFA enforcement, and environment-level restrictions.
  2. Schema
    A Schema defines the structure of entities and the data fields they expose. Every policy must be associated with a Schema for it to be valid.
    SchemaPolicies Using the Schema
    Global Enforcement (Baseline)Deny by Default, Least Privilege Enforcement
    Authentication & Session ControlsMulti-Factor Authentication Required, Restrict After-Hours Access
  3. Policy
    Policies define who can perform what action on which resource, under optional conditions. They can be created using Reva visual editor or authored in Cedar.
    • Examples:
      • Deny by Default Implements a baseline deny rule unless explicitly permitted.
      • Least Privilege Enforcement Ensures users have only the access needed for their role.
      • Require Justification for Deletion
        Checks for a valid justification before allowing delete actions.
      • Multi-Factor Authentication Required
        Enforces MFA using contextual data from login tokens.

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How to Navigate to the Library

  1. Go to the left-side main menu.
  2. Click the Library icon.
  3. This opens the Library, where you can browse or create:
    • Policy
    • Schema
    • Entity Type

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Benefits of Using the Library

  1. Reusability: Define once, reuse across multiple policies and applications.
  2. Standardization: Enforce consistent access patterns across your organization.
  3. Governance: Maintain version history, ownership, and audit trails.
  4. Scalability: Build complex authorization models quickly using modular components.
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