func main()

in src/checkout/main.go [140:224]
68 lines of code
7 McCabe index (conditional complexity)

func main() {
	var port string
	mustMapEnv(&port, "CHECKOUT_PORT")

	tp := initTracerProvider()
	defer func() {
		if err := tp.Shutdown(context.Background()); err != nil {
			log.Printf("Error shutting down tracer provider: %v", err)
		}
	}()

	mp := initMeterProvider()
	defer func() {
		if err := mp.Shutdown(context.Background()); err != nil {
			log.Printf("Error shutting down meter provider: %v", err)
		}
	}()

	err := runtime.Start(runtime.WithMinimumReadMemStatsInterval(time.Second))
	if err != nil {
		log.Fatal(err)
	}

	openfeature.SetProvider(flagd.NewProvider())
	openfeature.AddHooks(otelhooks.NewTracesHook())

	tracer = tp.Tracer("checkout")

	svc := new(checkout)

	mustMapEnv(&svc.shippingSvcAddr, "SHIPPING_ADDR")
	c := mustCreateClient(svc.shippingSvcAddr)
	svc.shippingSvcClient = pb.NewShippingServiceClient(c)
	defer c.Close()

	mustMapEnv(&svc.productCatalogSvcAddr, "PRODUCT_CATALOG_ADDR")
	c = mustCreateClient(svc.productCatalogSvcAddr)
	svc.productCatalogSvcClient = pb.NewProductCatalogServiceClient(c)
	defer c.Close()

	mustMapEnv(&svc.cartSvcAddr, "CART_ADDR")
	c = mustCreateClient(svc.cartSvcAddr)
	svc.cartSvcClient = pb.NewCartServiceClient(c)
	defer c.Close()

	mustMapEnv(&svc.currencySvcAddr, "CURRENCY_ADDR")
	c = mustCreateClient(svc.currencySvcAddr)
	svc.currencySvcClient = pb.NewCurrencyServiceClient(c)
	defer c.Close()

	mustMapEnv(&svc.emailSvcAddr, "EMAIL_ADDR")
	c = mustCreateClient(svc.emailSvcAddr)
	svc.emailSvcClient = pb.NewEmailServiceClient(c)
	defer c.Close()

	mustMapEnv(&svc.paymentSvcAddr, "PAYMENT_ADDR")
	c = mustCreateClient(svc.paymentSvcAddr)
	svc.paymentSvcClient = pb.NewPaymentServiceClient(c)
	defer c.Close()

	svc.kafkaBrokerSvcAddr = os.Getenv("KAFKA_ADDR")

	if svc.kafkaBrokerSvcAddr != "" {
		svc.KafkaProducerClient, err = kafka.CreateKafkaProducer([]string{svc.kafkaBrokerSvcAddr}, log)
		if err != nil {
			log.Fatal(err)
		}
	}

	log.Infof("service config: %+v", svc)

	lis, err := net.Listen("tcp", fmt.Sprintf(":%s", port))
	if err != nil {
		log.Fatal(err)
	}

	var srv = grpc.NewServer(
		grpc.StatsHandler(otelgrpc.NewServerHandler()),
	)
	pb.RegisterCheckoutServiceServer(srv, svc)
	healthpb.RegisterHealthServer(srv, svc)
	log.Infof("starting to listen on tcp: %q", lis.Addr().String())
	err = srv.Serve(lis)
	log.Fatal(err)
}