public static IFixerBuilder AddConsul(this IFixerBuilder builder, ConsulOptions options,
                                              HttpClientOptions httpClientOptions)
        {
            builder.Services.AddSingleton(options);
            if (!options.Enabled || !builder.TryRegister(RegistryName))
            {
                return(builder);
            }

            if (httpClientOptions.Type?.ToLowerInvariant() == "consul")
            {
                builder.Services.AddTransient <ConsulServiceDiscoveryMessageHandler>();
                builder.Services.AddHttpClient <IConsulHttpClient, ConsulHttpClient>()
                .AddHttpMessageHandler <ConsulServiceDiscoveryMessageHandler>();
                builder.Services.AddHttpClient <IHttpClient, ConsulHttpClient>()
                .AddHttpMessageHandler <ConsulServiceDiscoveryMessageHandler>();
            }

            builder.Services.AddTransient <IConsulServicesRegistry, ConsulServicesRegistry>();
            builder.Services.AddSingleton <IConsulClient>(c => new ConsulClient(cfg =>
            {
                if (!string.IsNullOrEmpty(options.Url))
                {
                    cfg.Address = new Uri(options.Url);
                }
            }));

            var registration = builder.CreateConsulAgentRegistration(options);

            if (registration is null)
            {
                return(builder);
            }

            builder.Services.AddSingleton(registration);
            builder.AddBuildAction(sp =>
            {
                var consulRegistration = sp.GetService <AgentServiceRegistration>();
                var client             = sp.GetService <IConsulClient>();

                client.Agent.ServiceRegister(consulRegistration);
            });

            return(builder);
        }
        private static AgentServiceRegistration CreateConsulAgentRegistration(this IFixerBuilder builder,
                                                                              ConsulOptions options)
        {
            var enabled       = options.Enabled;
            var consulEnabled = Environment.GetEnvironmentVariable("CONSUL_ENABLED")?.ToLowerInvariant();

            if (!string.IsNullOrWhiteSpace(consulEnabled))
            {
                enabled = consulEnabled == "true" || consulEnabled == "1";
            }

            if (!enabled)
            {
                return(null);
            }

            if (string.IsNullOrWhiteSpace(options.Address))
            {
                throw new ArgumentException("Consul address can not be empty.",
                                            nameof(options.PingEndpoint));
            }

            var uniqueId = string.Empty;

            using (var serviceProvider = builder.Services.BuildServiceProvider())
            {
                uniqueId = serviceProvider.GetRequiredService <IServiceId>().Id;
            }

            var pingInterval        = options.PingInterval <= 0 ? 5 : options.PingInterval;
            var removeAfterInterval = options.RemoveAfterInterval <= 0 ? 10 : options.RemoveAfterInterval;

            var registration = new AgentServiceRegistration
            {
                Name    = options.Service,
                ID      = $"{options.Service}:{uniqueId}",
                Address = options.Address,
                Port    = options.Port
            };

            if (!options.PingEnabled)
            {
                return(registration);
            }


            var scheme = options.Address.StartsWith("http", StringComparison.InvariantCultureIgnoreCase)
                ? string.Empty
                : "http://";
            var check = new AgentServiceCheck
            {
                Interval = TimeSpan.FromSeconds(pingInterval),
                DeregisterCriticalServiceAfter = TimeSpan.FromSeconds(removeAfterInterval),
                HTTP = $"{scheme}{options.Address}{(options.Port > 0 ? $":{options.Port}" : string.Empty)}/" +
                       $"{options.PingEndpoint}"
            };

            registration.Checks = new[] { check };

            return(registration);
        }