NativeOpenApi 1.3.1

NativeOpenApi

OpenAPI 3.1 document loading, linting, merging, and rendering abstractions for .NET 10 Native AOT applications.

Features

• OpenAPI Document Loading: Load OpenAPI specs from embedded resources (JSON and YAML supported)
• YAML Support: Full support for YAML format with AOT-compatible parsing
• Document Merging: Merge multiple partial specs into a consolidated document
• Linting: Validate OpenAPI specs against configurable rules
• HTML Rendering: Generate Redoc and Scalar documentation pages
• Native AOT Compatible: Fully optimized for ahead-of-time compilation

Installation

dotnet add package NativeOpenApi

Quick Start

1. Create your document loader

The loader automatically detects and parses both JSON (.json) and YAML (.yaml, .yml) files:

public class MyOpenApiDocumentLoader : OpenApiDocumentLoaderBase
{
    public MyOpenApiDocumentLoader(OpenApiResourceReader resourceReader) 
        : base(resourceReader) { }

    public override IReadOnlyList<OpenApiDocumentPart> LoadCommon()
    {
        return new List<OpenApiDocumentPart>
        {
            // YAML files
            Load("common-schemas", "openapi/common/schemas.yaml"),
            Load("common-responses", "openapi/common/responses.yaml"),
            Load("common-security", "openapi/common/security.yaml")
        };
    }

    public override IReadOnlyList<OpenApiDocumentPart> LoadPartials()
    {
        return new List<OpenApiDocumentPart>
        {
            // Mix of YAML and JSON files
            Load("users", "openapi/users/openapi.yaml"),
            Load("products", "openapi/products/openapi.json")
        };
    }
}

2. Create your document merger (optional)

public class MyOpenApiDocumentMerger : OpenApiDocumentMerger
{
    protected override string GetServerUrl()
    {
        var env = Environment.GetEnvironmentVariable("ENVIRONMENT") ?? "dev";
        return env switch
        {
            "prd" => "https://api.myapp.com",
            "hml" => "https://api-staging.myapp.com",
            _ => "https://localhost:5001"
        };
    }

    protected override string GetApiTitle() => "My API";
    protected override string GetApiDescription() => "My consolidated API documentation.";
}

3. Wire up the provider

var resourceReader = new OpenApiResourceReader(typeof(Program).Assembly, "MyApp.");
var loader = new MyOpenApiDocumentLoader(resourceReader);
var merger = new MyOpenApiDocumentMerger();
var linter = new OpenApiLinter(OpenApiLintOptions.Empty);
var provider = new OpenApiDocumentProvider(loader, merger, linter);

provider.WarmUp();

var json = provider.Document.Json;
var yaml = provider.Document.Yaml;

4. Render documentation pages

var renderer = new OpenApiHtmlRenderer();
var redocHtml = renderer.RenderRedoc("/openapi/v1/spec.json", "My API Docs");
var scalarHtml = renderer.RenderScalar("/openapi/v1/spec.json", "My API Docs");

Linting Rules

Configure linting rules using OpenApiLintOptions:

var options = new OpenApiLintOptions(
    RequiredErrorResponses: ["400", "401", "500"],
    SensitiveFieldNames: ["password", "token", "secret"],
    DisallowedGenericSegments: ["data", "items"]
);
var linter = new OpenApiLinter(options);

The linter validates:

• OpenAPI version is 3.1.0
• All paths include versioning (e.g., /v1/)
• All operations have security definitions (JwtBearer or OAuth2)
• Required error responses are present
• Sensitive fields have descriptions

API Reference

Core Classes

Document Types

Native AOT Compatibility

This library is fully compatible with .NET Native AOT compilation:

<PropertyGroup>
    <PublishAot>true</PublishAot>
</PropertyGroup>

All JSON/YAML parsing uses source-generated serialization contexts for optimal performance and trimming support.

Related Packages

• NativeOpenApiGenerator - Source Generator for automatic OpenAPI spec generation from NativeLambdaRouter endpoints

License

MIT