With multiple API versions Title and Description must be set for each route otherwise default values are taken

In case of multiple API versions, the following setup in the configuration method doesn’t work for Title and Description properties.

public void Configure(IApplicationBuilder app, IHostingEnvironment env)
{
    app.UseSwaggerWithApiExplorer(config =>
    {
        config.GeneratorSettings.OperationProcessors.TryGet<ApiVersionProcessor>().IncludedVersions = new[] { "1.0" };
        config.SwaggerRoute = "v1.0.json";
    });

    app.UseSwaggerWithApiExplorer(config =>
    {
        config.GeneratorSettings.OperationProcessors.TryGet<ApiVersionProcessor>().IncludedVersions = new[] { "2.0" };
        config.SwaggerRoute = "v2.0.json";
    });

    app.UseSwaggerUi3(typeof(Startup).GetTypeInfo().Assembly, config =>
    {
        config.SwaggerRoutes.Add(new SwaggerUi3Route("v1.0", "/v1.0.json"));
        config.SwaggerRoutes.Add(new SwaggerUi3Route("v2.0", "/v2.0.json"));

	// These settings are not considered, instead each route takes default title and description
        config.GeneratorSettings.Title = "My API Title";
        config.GeneratorSettings.Description = "My API functionalities.";
    });
}

To avoid default values you need to set on each of the individual configuration.

app.UseSwaggerWithApiExplorer(config =>
{
    config.GeneratorSettings.OperationProcessors.TryGet<ApiVersionProcessor>().IncludedVersions = new[] { "1.0" };
    config.SwaggerRoute = "v1.0.json";
    config.GeneratorSettings.Title = "My API Title";
    config.GeneratorSettings.Description = "My API functionalities.";
});

Please also refer to this.

[RicoSuter]

If you use app.UseSwaggerUi3 with SwaggerRoutes, it only renders the UI with the given routes, GeneratorSettings are ignored and must be set on the other UseSwaggerWithApiExplorer registrations. Also the assembly is ignored as the registration does not actually generate a spec (only renders UI) - you can remove this parameter.

I think we need to better document this…

[RicoSuter]

Ref: https://stackoverflow.com/questions/51710388/nswag-net-core-api-versioning-configuration