API Documentation

Adding documentation is often the final, pivotal step in making your versioned services available to clients and fosters their utilization. While there are many approaches to documenting your services, OpenAPI (formerly Swagger) has quickly become the de facto method for describing REST services.

The ASP.NET API versioning project provides several new API explorer implementations that make it easy to add versioning into your OpenAPI configurations. Each of these API explorers do all of the heavy lifting to discover and collate your REST services by API version. They do not directly rely on nor use any external OpenAPI libraries so that you can use them for other scenarios as well.

Any OpenAPI generator such as Swashbuckle, or NSwag that leverage the API Explorer can be used.

Web API

Everything you need to add versioned documentation to your API controllers using API Explorer extensions with [Swashbuckle][openapi-swashbuckle-old].

config.AddApiVersioning();

// (optional) format the version as "'v'major[.minor][-status]"
var apiExplorer = config.AddVersionedApiExplorer( o => o.GroupNameFormat = "'v'VVV" );

config.EnableSwagger(
    "{apiVersion}/swagger",
    swagger =>
    {
        swagger.MultipleApiVersions(
            ( apiDescription, version ) => apiDescription.GetGroupName() == version,
            info =>
            {
                foreach ( var group in apiExplorer.ApiDescriptions )
                {
                    info.Version( group.Name, $"Example API {group.ApiVersion}" );
                }
            } );
    } )
 .EnableSwaggerUi( swagger => swagger.EnableDiscoveryUrlSelector() );

Review the example project for additional setup and configuration options.

OData

Everything you need to add versioned documentation to your OData controllers using the OData API Explorer extensions with Swashbuckle.

configuration.AddApiVersioning();

var modelBuilder = new VersionedODataModelBuilder( configuration )
{
    ModelConfigurations = { new MyModelConfiguration() }
};

configuration.MapVersionedODataRoutes( "odata", "api", modelBuilder );

// (optional) format the version as "'v'major[.minor][-status]"
var apiExplorer = configuration.AddODataApiExplorer( o => o.GroupNameFormat = "'v'VVV" );

configuration.EnableSwagger(
    "{apiVersion}/swagger",
    swagger =>
    {
        swagger.MultipleApiVersions(
            ( apiDescription, version ) => apiDescription.GetGroupName() == version,
            info =>
            {
                foreach ( var group in apiExplorer.ApiDescriptions )
                {
                    info.Version( group.Name, $"Example API {group.ApiVersion}" );
                }
            } );
    } )
 .EnableSwaggerUi( swagger => swagger.EnableDiscoveryUrlSelector() );

Review the following example projects for additional setup and configuration options:

• OData OpenAPI Example
• Partial OData OpenAPI Example

Note

This API explorer does not directly tie into Swashbuckle with OData because that project also prescribes how API versioning is performed, which is incompatible with this project.