Pure.Authorization.OpenFGA.Model.Abstractions 0.1.0-preview.0.1.0

Pure.Authorization.OpenFGA.Model.Abstractions

OpenFGA authorization model interfaces for the Pure ecosystem — immutable, composable abstractions over objects, subjects, tuples, type definitions, relation rewrites and conditions.

Overview

Pure.Authorization.OpenFGA.Model.Abstractions defines a set of minimal, read-only interfaces that describe an OpenFGA authorization model and the relationship tuples written against it. Each interface exposes only getters — no mutation, no side effects. All string properties are typed as IString from Pure.Primitives.Abstractions, keeping the model decoupled from concrete string representations and from any particular OpenFGA client SDK.

Interfaces

Each concept lives in its own folder and namespace under Pure.Authorization.OpenFGA.Model.Abstractions.

IRewrite, ISubjectForm and ISubject have no members: each is the base of a closed set of variants, and consumers pattern-match on the concrete interface.

OpenFGA Naming

Names follow the OpenFGA DSL rather than the JSON/API wire format. Where they differ:

Design Principles

• Immutable — all interfaces expose only get properties; no setters, no methods that mutate state.
• Composable — complex structure is expressed through composition and IEnumerable<T> collections, allowing traversal without committing to a concrete collection type.
• Primitive-typed — string properties use IString from Pure.Primitives.Abstractions, not System.String, keeping the model framework-agnostic.
• AOT-compatible — the library sets IsAotCompatible=true and contains no reflection or code generation.

Dependencies

• Pure.Primitives.Abstractions — base interfaces for immutable primitive types (IString, INumber<T>, etc.)

Target Frameworks

• .NET 7
• .NET 8
• .NET 9
• .NET 10

Installation

dotnet add package Pure.Authorization.OpenFGA.Model.Abstractions

Usage

The closed sets (IRewrite, ISubjectForm, ISubject) are consumed by pattern matching. For example, rendering a relation definition back to the OpenFGA DSL:

using System.Linq;
using Pure.Authorization.OpenFGA.Model.Abstractions.Rewrite;
using Pure.Authorization.OpenFGA.Model.Abstractions.SubjectForm;

static string Dsl(IRewrite rewrite) =>
    rewrite switch
    {
        IDirect direct => $"[{string.Join(", ", direct.Forms.Select(FormDsl))}]",
        IComputedRelation computed => computed.Relation.TextValue,
        IRelationFrom from => $"{from.Relation.TextValue} from {from.Tupleset.TextValue}",
        IUnion union => $"({string.Join(" or ", union.Children.Select(Dsl))})",
        IIntersection both => $"({string.Join(" and ", both.Children.Select(Dsl))})",
        IDifference diff => $"({Dsl(diff.Base)} but not {Dsl(diff.Subtract)})",
        _ => throw new NotSupportedException(rewrite.GetType().Name),
    };

static string FormDsl(ISubjectForm form) =>
    form switch
    {
        ITypeForm type => type.Type.TextValue,
        ISubjectSetForm set => $"{set.Type.TextValue}#{set.Relation.TextValue}",
        IWildcardForm wildcard => $"{wildcard.Type.TextValue}:*",
        IConditionalForm conditional =>
            $"{FormDsl(conditional.Form)} with {conditional.Condition.TextValue}",
        _ => throw new NotSupportedException(form.GetType().Name),
    };