app.UseSwaggerUI(o =>
{
    var s1 = app.Environment.IsDevelopment()
        ? "/swagger/" : null;
    o.SwaggerEndpoint($"{s1}news-v2/swagger.json", "News API v2");
    o.SwaggerEndpoint($"{s1}news-v1/swagger.json", "News API v1");
    o.SwaggerEndpoint($"{s1}rss/swagger.json", "RSS");
});