tutorial-dotnet-JWTProtectedAPI setUpBearerJwtAuth()

Startup.cs

   private void setUpBearerJwtAuth(IServiceCollection services)
        {
            //Fetch JWT configuration from appsettings.json
            var jwtSection = Configuration.GetSection("jwtBearerTokenSettings");
            //Parse jwtSection from appsettings.json into Concrete Class "JWTBearerTokenSettings"
            services.Configure<JWTBearerTokenSettings>(jwtSection);
            var jwtBearerTokenSettings = jwtSection.Get<JWTBearerTokenSettings>();
            var key = Encoding.ASCII.GetBytes(jwtBearerTokenSettings.SecretKey);

            services.AddAuthentication(options =>
            {
                options.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
                options.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
            })
            .AddJwtBearer(options =>
            {
                options.RequireHttpsMetadata = false;
                options.SaveToken = true;
                options.TokenValidationParameters = new TokenValidationParameters()
                {
                    ValidateIssuer = true,
                    ValidIssuer = jwtBearerTokenSettings.Issuer,
                    ValidateAudience = true,
                    ValidAudience = jwtBearerTokenSettings.Audience,
                    ValidateIssuerSigningKey = true,
                    IssuerSigningKey = new SymmetricSecurityKey(key),
                    ValidateLifetime = true,
                    ClockSkew = TimeSpan.Zero
                };
            });
        }