SwaggerEnrichers

SwaggerEnrichers is a C# package that offers a more flexible and convenient way to add ISchemaFilter and IParameterFilter using attributes. While you can use the SwaggerSchemaAttribute from Swashbuckle.AspNetCore.Annotations, SwaggerEnrichers allows you to configure example values, value type and so on.

How it works

SwaggerEnrichers comprises an ISchemaFilter and an IParameterFilter that analyze incoming classes, parameters, and properties. The filters look for attributes that implement IParameterEnricher or ISchemaEnricher, once they find these attributes, they use their Enrich methods to modify the schema or parameter.

Instalation

SwaggerEnrichers is available on NuGet and can be installed via the below commands:

$ Install-Package SwaggerEnrichers

or via the .NET Core CLI:

$ dotnet add package SwaggerEnrichers

Getting started

To get started with SwaggerEnrichers, you need to add the necessary filters to SwaggerGen:

builder.Services.AddSwaggerGen(options =>
{
    options.AddEnricherFilters();
});

After that, you need to create an attribute that implements ISchemaFilter or IParameterFilter. You can create an attribute that implements both as well:

public class ProductViewIdAttribute : Attribute, ISchemaEnricher, IParameterEnricher
{
    public void Enrich(OpenApiSchema schema)
    {
        schema.Title = "Product Id";
        schema.Description = "Product identifier";
        schema.Example = new OpenApiInteger(3);
    }

    public void Enrich(OpenApiParameter parameter)
    {
        parameter.Name = "Product Id";
        parameter.Description = "Product identifier";
        parameter.Schema.Example = null;
    }
}

public class ProductViewNameAttribute : Attribute, ISchemaEnricher, IParameterEnricher
{
    public void Enrich(OpenApiSchema schema)
    {
        schema.Title = "Product Name";
        schema.Description = "Name of product";
        schema.Example = new OpenApiString("Apple Watch");
    }

    public void Enrich(OpenApiParameter parameter)
    {
        parameter.Name = "Product Name";
        parameter.Description = "Name of product";
        parameter.Schema.Example = null;
    }
}

Now, you can apply these attributes to any class, parameter, property, or member:

public class ProductView
{
    [ProductViewId]
    public required int Id { get; init; }
    [ProductViewName]
    public required string Name { get; init; }
    [ProductViewPrice]
    public required decimal Price { get; init; }
    [ProductViewType]
    public required string Type { get; init; }
}

[Route("api/product")]
[ApiController]
public class ProductController : ControllerBase
{
    [HttpGet]
    [Route("id/{id}")]
    public ActionResult<ProductView> GetProductById([ProductViewId] string id)
    {
        return Ok();
    }
    
    [HttpGet]
    [Route("name/{name}")]
    public ActionResult<ProductView> GetProductByName([ProductViewName] string name)
    {
        return Ok();
    }

    [HttpGet]
    public ActionResult<List<ProductView>> GetProducts([FromQuery] GetProductsQueryView getProductsQueryView)
    {
        return Ok();
    }

    [HttpPost]
    public ActionResult PostProduct(ProductView productView)
    {
        return NoContent();
    }
}

For more complex examples see Demo project