TeknixIT.OpenApiGenerator.Server 1.0.0

TeknixIT.OpenApiGenerator.Server

A C# source generator that creates ASP.NET Core contracts (DTOs) and controllers from OpenAPI specifications at compile time.

Features

• Compile-time code generation - No runtime overhead, fully integrated into your build process
• OpenAPI 3.x support - Works with YAML and JSON specifications
• Highly configurable - Control every aspect of code generation
• Contract generation - Generate DTOs as records or classes
• Controller generation - Generate controller stubs with proper routing
• Validation attributes - Automatic generation of validation attributes from schema constraints
• XML documentation - Generate XML docs from OpenAPI descriptions
• Async support - Generate async controller methods
• .NET Standard 2.0 - Compatible with .NET 8, 9, 10+

Installation

dotnet add package TeknixIT.OpenApiGenerator.Server

Quick Start

1. Add your OpenAPI specification file to your project (e.g., openapi.yaml)

2. Configure the generator in your .csproj file:

<ItemGroup>
  <OpenApiGeneratorServer Include="openapi.yaml" />
</ItemGroup>

3. Build your project - contracts and controllers will be generated automatically

Configuration

Basic Configuration

The simplest setup uses default settings:

<ItemGroup>
  <OpenApiGeneratorServer Include="openapi.yaml" />
</ItemGroup>

Advanced Configuration

Customize generation with metadata:

<ItemGroup>
  <OpenApiGeneratorServer Include="openapi.yaml">
    <GenerateControllers>true</GenerateControllers>
    <UseRecords>true</UseRecords>
    <BaseNamespace>MyApp.Generated</BaseNamespace>
    <ContractsNamespace>Contracts</ContractsNamespace>
    <ControllersNamespace>Controllers</ControllersNamespace>
    <GenerateValidationAttributes>true</GenerateValidationAttributes>
    <GenerateXmlDocumentation>true</GenerateXmlDocumentation>
    <UseAsyncControllers>true</UseAsyncControllers>
    <AddApiControllerAttribute>true</AddApiControllerAttribute>
    <ControllerBaseClass>ControllerBase</ControllerBaseClass>
    <ControllerGroupingStrategy>ByTag</ControllerGroupingStrategy>
  </OpenApiGeneratorServer>
</ItemGroup>

Configuration Options

Example

Given an OpenAPI specification:

openapi: 3.1.0
info:
  title: My API
  version: 1.0.0
paths:
  /users/{id}:
    get:
      operationId: GetUser
      parameters:
        - name: id
          in: path
          required: true
          schema:
            type: string
            format: uuid
      responses:
        '200':
          description: Success
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/User'
components:
  schemas:
    User:
      type: object
      required:
        - id
        - name
      properties:
        id:
          type: string
          format: uuid
        name:
          type: string
          maxLength: 100

The generator creates:

Contract (DTO):

namespace Generated.Contracts;

/// <summary>
/// User
/// </summary>
public record User
{
    /// <summary>
    /// Gets or sets Id.
    /// </summary>
    [Required]
    public Guid Id { get; set; }

    /// <summary>
    /// Gets or sets Name.
    /// </summary>
    [Required]
    [StringLength(100)]
    public string Name { get; set; }
}

Controller:

namespace Generated.Controllers;

[ApiController]
public abstract class UsersControllerBase : ControllerBase
{
    /// <summary>
    /// GetUser
    /// </summary>
    /// <param name="id"></param>
    [HttpGet("/users/{id}")]
    public abstract Task<IActionResult> GetUser([FromRoute] Guid id);
}

Requirements

• .NET 8, 9, 10+
• OpenAPI 3.x specification (YAML or JSON)

Repository

https://github.com/flavien-chenu/openapi-generator

License

MIT