Swagger - how to show a more complex response example - ASP.net Core Web API

Question

I have a swagger definition and I'm using XML comments to describe the request and response and give meaningful samples. Example model as follows:

/// <summary>Created item information.</summary>
public class ItemCreated
{
    /// <summary>Outcome of the item being created.</summary>
    /// <value>The outcome.</value>
    /// <example>Item has been Created</example>
    public string Outcome { get; set; }

    /// <summary>Unique item reference.</summary>
    /// <value>The Item reference.</value>
    /// <example>6001002982178</example>
    public string Reference { get; set; }

    /// <summary>The external reference for the package.</summary>
    /// <value>The carrier reference.</value>
    /// <example>5558702516</example>
    public string ExternalReference { get; set; }

    /// <summary>The items documents.</summary>
    /// <value>The items documentation.</value>
    /// <example>???</example>
    public List<Documentation> Documents { get; set; }
}


/// <summary>Item documentation information.</summary>
[JsonObject("Documentation")]
public class Documentation
{
    /// <summary>The document in base64 format.</summary>
    /// <value>The document base64 string.</value>
    /// <example>JVBERi0xLjMNCjEgMCBvYmoNCjw8DQovVHlwM...</example>
    [JsonProperty("Document")]
    public string Document { get; set; }

    /// <summary>The type of the document.</summary>
    /// <value>The documentation type.</value>
    /// <example>ITEMDOCUMENT_SLIP1</example>
    public DocumentationType Type { get; set; }

    /// <summary>Document format.</summary>
    /// <value>The format of the document.</value>
    /// <example>Pdf</example>
    public string Format { get; set; }

    /// <summary>The document resource uri.</summary>
    /// <value>The link to the document resource.</value>
    public string Link { get; set; }
}

Showing as this in swagger:

What I need is to show a more complex response example. You can see one of the properties is an array here - I'd like to show multiple document types - so multiple array items. How do I show this? The "" node doens't allow for multiple examples in an array.

Thanks for any points in advance!

Answer 1

One way to do this would be using Schema Filters:

[SwaggerSchemaFilter(typeof(ItemCreatedSchemaFilter))
public class ItemCreated
{
    ⋮
}

public class ItemCreatedSchemaFilter : ISchemaFilter
{
    public void Apply(OpenApiSchema schema, SchemaFilterContext context)
    {
      if (schema.Type == typeof(ItemCreated))
      {
        schema.Example = new OpenApiObject
        {
            // Other Properties
            ["Documents"] = new OpenApiArray
            {
                new OpenApiObject
                {
                    // Other Properties
                    ["Document"] = new OpenApiString("JVBERi0xLjMNCjEgMCBvYmoNCjw8DQovVHlwM..."),
                    ["Format"] = new OpenApiString("Pdf")
                },
                new OpenApiObject
                {
                    // Other Properties
                    ["Document"] = new OpenApiString("Something else"),
                    ["Format"] = new OpenApiString("Something else")
                }
            }
        };
      }
    }
}

Reference: Apply Schema Filters to Specific Types

Remember to add the new filter to the SwaggerGen options:

services.AddSwaggerGen(c =>
{
     c.SchemaFilter<ItemCreatedFilter>();

     ...
}