Swashbuckle Swagger - How to annotate content types?

Question

How do I annotate my ASP.NET WebAPI actions so that the swagger metadata includes the content-types that my resources support?

Specifically, I want the documentation to show that one of my resources can return the 'original' application/json and application/xml but also now returns a new format, application/vnd.blah+json or +xml.

Answer 1

Extending @VisualBean's answer.

On a Controller's API method, you could use the code below to set an Attribute like:

[SwaggerResponseContentType(responseType:"application/pdf", Exclusive=true)] public HttpResponseMessage GetAuthorityForm(string id) { .... 

Note: 'Exclusive=true' will remove all other content types, otherwise using the new Attribute will add a new Response Content Type in the Swagger UI drop down. It will NOT modify your Controller or API, just the documentation.

SwaggerConfig.cs

 GlobalConfiguration.Configuration             .EnableSwagger(c =>  // Set filter to apply Custom Content Types to operations  //  c.OperationFilter<ResponseContentTypeOperationFilter>(); 

SwaggerResponseContentTypeAttribute.cs

/// <summary> /// SwaggerResponseContentTypeAttribute /// </summary> [AttributeUsage(AttributeTargets.Method)] public sealed class SwaggerResponseContentTypeAttribute : Attribute {     /// <summary>     /// SwaggerResponseContentTypeAttribute     /// </summary>     /// <param name="responseType"></param>     public SwaggerResponseContentTypeAttribute(string responseType)     {         ResponseType = responseType;     }     /// <summary>     /// Response Content Type     /// </summary>     public string ResponseType { get; private set; }      /// <summary>     /// Remove all other Response Content Types     /// </summary>     public bool Exclusive { get; set; } } 

ResponseContentTypeOperationFilter.cs

public class ResponseContentTypeOperationFilter : IOperationFilter {     public void Apply(Operation operation, SchemaRegistry schemaRegistry, ApiDescription apiDescription)     {         var requestAttributes = apiDescription.GetControllerAndActionAttributes<SwaggerResponseContentTypeAttribute>().FirstOrDefault();          if (requestAttributes != null)         {             if (requestAttributes.Exclusive)                 operation.produces.Clear();              operation.produces.Add(requestAttributes.ResponseType);         }     } }