Startup.cs

using Microsoft.AspNetCore.HttpOverrides;
using Microsoft.OpenApi.Models;

namespace SwaggerImplementation.Api
{
    public class Startup
    {
        public void ConfigureServices(IServiceCollection services)
        {
            services.AddSwaggerGen(c =>
            {
                c.SwaggerDoc("v1", new OpenApiInfo { Title = "Employee API", Version = "v1" });
                c.AddSecurityDefinition("Bearer", new OpenApiSecurityScheme
                {
                    In = ParameterLocation.Header,
                    Description = "Please insert JWT with Bearer into field",
                    Name = "Authorization",
                    Type = SecuritySchemeType.ApiKey
                });
                c.AddSecurityRequirement(new OpenApiSecurityRequirement {
                {
                  new OpenApiSecurityScheme
                  {
                    Reference = new OpenApiReference
                    {
                      Type = ReferenceType.SecurityScheme,
                      Id = "Bearer"
                    }
                   },
                   new string[] { }
                 }
                });
                c.CustomSchemaIds(x => x.FullName);
            });
            services.AddControllers();

        }
        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
        {
            app.UseRouting();
            app.UseSwagger();
            app.UseSwaggerUI(c =>
            {
                c.SwaggerEndpoint("/swagger/v1/swagger.json", "Employee V1");
            });
            app.UseEndpoints(endpoints => {
                endpoints.MapControllers();
            });
        }
    }
}