Swagger not working correctly with multiple versions of ASP.NET WebApi app

ValueV1Controller.cs

[RoutePrefix("api/v1/value")]
public class ValueV1Controller : ApiController
{
    [Route("get")]
    public IEnumerable<string> Get()
    {
        return new string[] { "value1", "value2" };
    }
}

ValueV2Controller.cs

[RoutePrefix("api/v2/value")]
public class ValueV2Controller : ApiController
{
    [Route("get")]
    public IEnumerable<string> Get()
    {
        return new string[] { "value1.2", "value2.2" };
    }
}

SwaggerConfig.cs

public class SwaggerConfig
{
    public static void Register()
    {
        var thisAssembly = typeof(SwaggerConfig).Assembly;

        GlobalConfiguration.Configuration
            .EnableSwagger(c =>
            {
                c.MultipleApiVersions(
                    (apiDesc, version) =>
                    {
                        var path = apiDesc.RelativePath.Split('/');
                        var pathVersion = path[1];

                        return CultureInfo.InvariantCulture.CompareInfo.IndexOf(pathVersion, version, CompareOptions.IgnoreCase) >= 0;
                    },
                    (vc) =>
                    {
                        vc.Version("v2", "Swashbuckle Dummy API V2");
                        vc.Version("v1", "Swashbuckle Dummy API V1");
                    });
            })
            .EnableSwaggerUi(c =>
            {
                c.EnableDiscoveryUrlSelector();
            });
    }
}

Solved it by:

1. Adding the Microsoft.AspNet.WebApi.Versioning.ApiExplorer package

2. Using the versioned API explorer as below (note that I had to move the code from SwaggerConfig.cs in WebApiConfig.cs due to initialization issues):

       var apiExplorer = config.AddVersionedApiExplorer(options => {
           options.GroupNameFormat = "'v'VVV";
       });
   
       var versionSupportResolver = new Func<ApiDescription, string, bool>((apiDescription, version) => apiDescription.GetGroupName() == version);
   
       var versionInfoBuilder = new Action<VersionInfoBuilder>(info => {
           foreach (var group in apiExplorer.ApiDescriptions)
           {
               info.Version(group.Name, $"MyAPI v{group.ApiVersion}");
           }
       });
   
       config
           .EnableSwagger("{apiVersion}/swagger", swagger => {
               swagger.OperationFilter<SwaggerDefaultValues>();
               swagger.MultipleApiVersions(versionSupportResolver, versionInfoBuilder);
               swagger.IncludeXmlComments(WebApiConfig.XmlCommentsFilePath);
           })
           .EnableSwaggerUi(swaggerUi => {
               swaggerUi.EnableDiscoveryUrlSelector();
               swaggerUi.DocExpansion(DocExpansion.List);
           });