How to define base url in swashbuckle 5.0 within asp.net core 3.1

[KamranShahid]

I am using asp.net core 3.1 with swashbuckle 5. I am not able tofind the way for defining base url. RootUrl option seem to be not coming or (may be i am not able to call it)

Please let me know how to define it

 private static void SwaggerInjection(IServiceCollection services)
        {
            services.AddSwaggerGen(x =>
            {               
                x.SwaggerDoc("v1", new OpenApiInfo { Title = "Portal Backend APIs", Version = "v1" });
                x.DescribeAllEnumsAsStrings();
                x.TagActionsBy(api =>
                {
                    if (api.GroupName != null)
                    {
                        return new[] { api.GroupName };
                    }

                    var controllerActionDescriptor = api.ActionDescriptor as ControllerActionDescriptor;
                    if (controllerActionDescriptor != null)
                    {
                        return new[] { controllerActionDescriptor.ControllerName };
                    }

                    throw new InvalidOperationException("Unable to determine tag for endpoint.");
                });
                x.DocInclusionPredicate((name, api) => true);
                x.AddSecurityDefinition("Bearer", // name the security scheme
                    new OpenApiSecurityScheme
                    {
                        Description = "JWT Authorization header using the Bearer scheme.",
                        Type = SecuritySchemeType.Http, // we set the scheme type to http since we're using bearer authentication
                        Scheme = "bearer" // the name of the HTTP Authorization scheme to be used in the Authorization header. In this case "bearer".
                    });
                x.AddSecurityRequirement(new OpenApiSecurityRequirement{
                    {
                        new OpenApiSecurityScheme{
                            Reference = new OpenApiReference{
                                Id = "Bearer", // the name of the previously defined security scheme.
                                Type = ReferenceType.SecurityScheme
                            }
                        },new List<string>()
                    }
                });
                // to show API description and other stuff on swagger
                var xmlFile = $"{Assembly.GetExecutingAssembly().GetName().Name}.xml";
                var xmlPath = Path.Combine(AppContext.BaseDirectory, xmlFile);
                x.IncludeXmlComments(xmlPath);
            });
        }