Merge branch 'main' of https://git.tornberg.me/mats/go-cart-actor

cmd/cart/checkout_server.go

@@ -29,7 +29,7 @@ func (a *App) HandleCheckoutRequests(amqpUrl string, mux *http.ServeMux) {
 	orderHandler := NewAmqpOrderHandler(conn)
 	orderHandler.DefineTopics()
 
-	mux.HandleFunc("/push", func(w http.ResponseWriter, r *http.Request) {
+	mux.HandleFunc("POST /push", func(w http.ResponseWriter, r *http.Request) {
 
 		if r.Method != http.MethodPost {
 			w.WriteHeader(http.StatusMethodNotAllowed)
@@ -59,7 +59,7 @@ func (a *App) HandleCheckoutRequests(amqpUrl string, mux *http.ServeMux) {
 			w.WriteHeader(http.StatusInternalServerError)
 			return
 		}
-		err = a.klarnaClient.AcknowledgeOrder(orderId)
+		err = a.klarnaClient.AcknowledgeOrder(r.Context(), orderId)
 		if err != nil {
 			log.Printf("Error acknowledging order: %v\n", err)
 		}
@@ -67,7 +67,7 @@ func (a *App) HandleCheckoutRequests(amqpUrl string, mux *http.ServeMux) {
 		w.WriteHeader(http.StatusOK)
 	})
 
-	mux.HandleFunc("/checkout", a.server.CheckoutHandler(func(order *CheckoutOrder, w http.ResponseWriter) error {
+	mux.HandleFunc("GET /checkout", a.server.CheckoutHandler(func(order *CheckoutOrder, w http.ResponseWriter) error {
 		w.Header().Set("Content-Type", "text/html; charset=utf-8")
 		w.Header().Set("Permissions-Policy", "payment=(self \"https://js.stripe.com\" \"https://m.stripe.network\" \"https://js.playground.kustom.co\")")
 		w.WriteHeader(http.StatusOK)
@@ -75,7 +75,7 @@ func (a *App) HandleCheckoutRequests(amqpUrl string, mux *http.ServeMux) {
 		return err
 	}))
 
-	mux.HandleFunc("/confirmation/{order_id}", func(w http.ResponseWriter, r *http.Request) {
+	mux.HandleFunc("GET /confirmation/{order_id}", func(w http.ResponseWriter, r *http.Request) {
 
 		orderId := r.PathValue("order_id")
 		order, err := a.klarnaClient.GetOrder(orderId)
@@ -102,7 +102,7 @@ func (a *App) HandleCheckoutRequests(amqpUrl string, mux *http.ServeMux) {
 		w.WriteHeader(http.StatusOK)
 		fmt.Fprintf(w, tpl, order.HTMLSnippet)
 	})
-	mux.HandleFunc("/validate", func(w http.ResponseWriter, r *http.Request) {
+	mux.HandleFunc("POST /validate", func(w http.ResponseWriter, r *http.Request) {
 		log.Printf("Klarna order validation, method: %s", r.Method)
 		if r.Method != "POST" {
 			w.WriteHeader(http.StatusMethodNotAllowed)

cmd/cart/klarna-client.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"context"
 	"encoding/json"
 	"fmt"
 	"io"
@@ -64,13 +65,13 @@ func (k *KlarnaClient) getOrderResponse(res *http.Response) (*CheckoutOrder, err
 	return nil, fmt.Errorf("%s", res.Status)
 }
 
-func (k *KlarnaClient) CreateOrder(reader io.Reader) (*CheckoutOrder, error) {
+func (k *KlarnaClient) CreateOrder(ctx context.Context, reader io.Reader) (*CheckoutOrder, error) {
 	//bytes.NewReader(reply.Payload)
 	req, err := http.NewRequest("POST", k.Url+"/checkout/v3/orders", reader)
 	if err != nil {
 		return nil, err
 	}
-
+	req.WithContext(ctx)
 	req.Header.Add("Content-Type", "application/json")
 	req.SetBasicAuth(k.UserName, k.Password)
 
@@ -82,13 +83,14 @@ func (k *KlarnaClient) CreateOrder(reader io.Reader) (*CheckoutOrder, error) {
 	return k.getOrderResponse(res)
 }
 
-func (k *KlarnaClient) UpdateOrder(orderId string, reader io.Reader) (*CheckoutOrder, error) {
+func (k *KlarnaClient) UpdateOrder(ctx context.Context, orderId string, reader io.Reader) (*CheckoutOrder, error) {
 	//bytes.NewReader(reply.Payload)
 	req, err := http.NewRequest("POST", fmt.Sprintf("%s/checkout/v3/orders/%s", k.Url, orderId), reader)
 	if err != nil {
 		return nil, err
 	}
 
+	req.WithContext(ctx)
 	req.Header.Add("Content-Type", "application/json")
 	req.SetBasicAuth(k.UserName, k.Password)
 
@@ -100,12 +102,12 @@ func (k *KlarnaClient) UpdateOrder(orderId string, reader io.Reader) (*CheckoutO
 	return k.getOrderResponse(res)
 }
 
-func (k *KlarnaClient) AbortOrder(orderId string) error {
+func (k *KlarnaClient) AbortOrder(ctx context.Context, orderId string) error {
 	req, err := http.NewRequest("POST", fmt.Sprintf("%s/checkout/v3/orders/%s/abort", k.Url, orderId), nil)
 	if err != nil {
 		return err
 	}
-
+	req.WithContext(ctx)
 	req.SetBasicAuth(k.UserName, k.Password)
 
 	_, err = http.DefaultClient.Do(req)
@@ -113,11 +115,12 @@ func (k *KlarnaClient) AbortOrder(orderId string) error {
 }
 
 // ordermanagement/v1/orders/{order_id}/acknowledge
-func (k *KlarnaClient) AcknowledgeOrder(orderId string) error {
+func (k *KlarnaClient) AcknowledgeOrder(ctx context.Context, orderId string) error {
 	req, err := http.NewRequest("POST", fmt.Sprintf("%s/ordermanagement/v1/orders/%s/acknowledge", k.Url, orderId), nil)
 	if err != nil {
 		return err
 	}
+	req.WithContext(ctx)
 	id := uuid.New()
 
 	req.SetBasicAuth(k.UserName, k.Password)

cmd/cart/main.go

@@ -1,15 +1,16 @@
 package main
 
 import (
+	"context"
 	"encoding/json"
 	"fmt"
 	"log"
+	"net"
 	"net/http"
 	"net/http/pprof"
 	"os"
 	"os/signal"
 	"strings"
-	"syscall"
 	"time"
 
 	"git.tornberg.me/go-cart-actor/pkg/actor"
@@ -21,6 +22,7 @@ import (
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/client_golang/prometheus/promauto"
 	"github.com/prometheus/client_golang/prometheus/promhttp"
+	"go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"
 )
 
 var (
@@ -158,7 +160,15 @@ func main() {
 	// go diskStorage.SaveLoop(10 * time.Second)
 	UseDiscovery(pool)
 
-	mux.Handle("/cart/", http.StripPrefix("/cart", syncedServer.Serve()))
+	ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt)
+	defer stop()
+
+	otelShutdown, err := setupOTelSDK(ctx)
+	if err != nil {
+		log.Fatalf("Unable to start otel %v", err)
+	}
+
+	syncedServer.Serve(mux)
 	// only for local
 	mux.HandleFunc("GET /add/remote/{host}", func(w http.ResponseWriter, r *http.Request) {
 		pool.AddRemote(r.PathValue("host"))
@@ -202,23 +212,41 @@ func main() {
 
 	mux.HandleFunc("/openapi.json", ServeEmbeddedOpenAPI)
 
-	sigs := make(chan os.Signal, 1)
+	srv := &http.Server{
-	done := make(chan bool, 1)
+		Addr:         ":8080",
-	signal.Notify(sigs, syscall.SIGTERM)
+		BaseContext:  func(net.Listener) context.Context { return ctx },
+		ReadTimeout:  10 * time.Second,
+		WriteTimeout: 20 * time.Second,
+		Handler:      otelhttp.NewHandler(mux, "/"),
+	}
 
-	go func() {
+	defer func() {
-		sig := <-sigs
+
-		fmt.Println("Shutting down due to signal:", sig)
+		fmt.Println("Shutting down due to signal")
+		otelShutdown(context.Background())
 		diskStorage.Close()
 		pool.Close()
 
-		done <- true
+	}()
+
+	srvErr := make(chan error, 1)
+	go func() {
+		srvErr <- srv.ListenAndServe()
 	}()
 
 	log.Print("Server started at port 8080")
-	go http.ListenAndServe(":8080", mux)
+
 	go http.ListenAndServe(":8081", debugMux)
-	<-done
+
+	select {
+	case err = <-srvErr:
+		// Error when starting HTTP server.
+		log.Fatalf("Unable to start server: %v", err)
+	case <-ctx.Done():
+		// Wait for first CTRL+C.
+		// Stop receiving signal notifications as soon as possible.
+		stop()
+	}
 
 }
 

cmd/cart/otel.go

@@ -0,0 +1,117 @@
+package main
+
+import (
+	"context"
+	"errors"
+	"time"
+
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploggrpc"
+	"go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc"
+	"go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc"
+	"go.opentelemetry.io/otel/log/global"
+	"go.opentelemetry.io/otel/propagation"
+	"go.opentelemetry.io/otel/sdk/log"
+	"go.opentelemetry.io/otel/sdk/metric"
+	"go.opentelemetry.io/otel/sdk/trace"
+)
+
+// setupOTelSDK bootstraps the OpenTelemetry pipeline.
+// If it does not return an error, make sure to call shutdown for proper cleanup.
+func setupOTelSDK(ctx context.Context) (func(context.Context) error, error) {
+	var shutdownFuncs []func(context.Context) error
+	var err error
+
+	// shutdown calls cleanup functions registered via shutdownFuncs.
+	// The errors from the calls are joined.
+	// Each registered cleanup will be invoked once.
+	shutdown := func(ctx context.Context) error {
+		var err error
+		for _, fn := range shutdownFuncs {
+			err = errors.Join(err, fn(ctx))
+		}
+		shutdownFuncs = nil
+		return err
+	}
+
+	// handleErr calls shutdown for cleanup and makes sure that all errors are returned.
+	handleErr := func(inErr error) {
+		err = errors.Join(inErr, shutdown(ctx))
+	}
+
+	// Set up propagator.
+	prop := newPropagator()
+	otel.SetTextMapPropagator(prop)
+
+	// Set up trace provider.
+	tracerProvider, err := newTracerProvider()
+	if err != nil {
+		handleErr(err)
+		return shutdown, err
+	}
+	shutdownFuncs = append(shutdownFuncs, tracerProvider.Shutdown)
+	otel.SetTracerProvider(tracerProvider)
+
+	// Set up meter provider.
+	meterProvider, err := newMeterProvider()
+	if err != nil {
+		handleErr(err)
+		return shutdown, err
+	}
+	shutdownFuncs = append(shutdownFuncs, meterProvider.Shutdown)
+	otel.SetMeterProvider(meterProvider)
+
+	// Set up logger provider.
+	loggerProvider, err := newLoggerProvider()
+	if err != nil {
+		handleErr(err)
+		return shutdown, err
+	}
+	shutdownFuncs = append(shutdownFuncs, loggerProvider.Shutdown)
+	global.SetLoggerProvider(loggerProvider)
+
+	return shutdown, err
+}
+
+func newPropagator() propagation.TextMapPropagator {
+	return propagation.NewCompositeTextMapPropagator(
+		propagation.TraceContext{},
+		propagation.Baggage{},
+	)
+}
+
+func newTracerProvider() (*trace.TracerProvider, error) {
+	traceExporter, err := otlptracegrpc.New(context.Background())
+	if err != nil {
+		return nil, err
+	}
+
+	tracerProvider := trace.NewTracerProvider(
+		trace.WithBatcher(traceExporter,
+			// Default is 5s. Set to 1s for demonstrative purposes.
+			trace.WithBatchTimeout(time.Second)),
+	)
+	return tracerProvider, nil
+}
+
+func newMeterProvider() (*metric.MeterProvider, error) {
+	exporter, err := otlpmetricgrpc.New(context.Background())
+	if err != nil {
+		return nil, err
+	}
+
+	provider := metric.NewMeterProvider(metric.WithReader(metric.NewPeriodicReader(exporter)))
+	return provider, nil
+}
+
+func newLoggerProvider() (*log.LoggerProvider, error) {
+	logExporter, err := otlploggrpc.New(context.Background())
+	if err != nil {
+		return nil, err
+	}
+
+	loggerProvider := log.NewLoggerProvider(
+		log.WithProcessor(log.NewBatchProcessor(logExporter)),
+	)
+	return loggerProvider, nil
+}

cmd/cart/pool-server.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"bytes"
+	"context"
 	"encoding/json"
 	"fmt"
 	"log"
@@ -17,6 +18,13 @@ import (
 	"github.com/gogo/protobuf/proto"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/client_golang/prometheus/promauto"
+	"go.opentelemetry.io/contrib/bridges/otelslog"
+	"go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"
+
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/metric"
+	"go.opentelemetry.io/otel/trace"
 )
 
 var (
@@ -59,7 +67,7 @@ func (s *PoolServer) GetCartHandler(w http.ResponseWriter, r *http.Request, id c
 
 func (s *PoolServer) AddSkuToCartHandler(w http.ResponseWriter, r *http.Request, id cart.CartId) error {
 	sku := r.PathValue("sku")
-	msg, err := GetItemAddMessage(sku, 1, getCountryFromHost(r.Host), nil)
+	msg, err := GetItemAddMessage(r.Context(), sku, 1, getCountryFromHost(r.Host), nil)
 	if err != nil {
 		return err
 	}
@@ -191,14 +199,14 @@ type SetCartItems struct {
 	Items   []Item `json:"items"`
 }
 
-func getMultipleAddMessages(items []Item, country string) []proto.Message {
+func getMultipleAddMessages(ctx context.Context, items []Item, country string) []proto.Message {
 	wg := sync.WaitGroup{}
 	mu := sync.Mutex{}
 	msgs := make([]proto.Message, 0, len(items))
 	for _, itm := range items {
 		wg.Go(
 			func() {
-				msg, err := GetItemAddMessage(itm.Sku, itm.Quantity, country, itm.StoreId)
+				msg, err := GetItemAddMessage(ctx, itm.Sku, itm.Quantity, country, itm.StoreId)
 				if err != nil {
 					log.Printf("error adding item %s: %v", itm.Sku, err)
 					return
@@ -221,7 +229,7 @@ func (s *PoolServer) SetCartItemsHandler(w http.ResponseWriter, r *http.Request,
 
 	msgs := make([]proto.Message, 0, len(setCartItems.Items)+1)
 	msgs = append(msgs, &messages.ClearCartRequest{})
-	msgs = append(msgs, getMultipleAddMessages(setCartItems.Items, setCartItems.Country)...)
+	msgs = append(msgs, getMultipleAddMessages(r.Context(), setCartItems.Items, setCartItems.Country)...)
 
 	reply, err := s.ApplyLocal(id, msgs...)
 	if err != nil {
@@ -237,7 +245,7 @@ func (s *PoolServer) AddMultipleItemHandler(w http.ResponseWriter, r *http.Reque
 		return err
 	}
 
-	reply, err := s.ApplyLocal(id, getMultipleAddMessages(setCartItems.Items, setCartItems.Country)...)
+	reply, err := s.ApplyLocal(id, getMultipleAddMessages(r.Context(), setCartItems.Items, setCartItems.Country)...)
 	if err != nil {
 		return err
 	}
@@ -257,7 +265,7 @@ func (s *PoolServer) AddSkuRequestHandler(w http.ResponseWriter, r *http.Request
 	if err != nil {
 		return err
 	}
-	msg, err := GetItemAddMessage(addRequest.Sku, int(addRequest.Quantity), addRequest.Country, addRequest.StoreId)
+	msg, err := GetItemAddMessage(r.Context(), addRequest.Sku, int(addRequest.Quantity), addRequest.Country, addRequest.StoreId)
 	if err != nil {
 		return err
 	}
@@ -302,7 +310,7 @@ func getLocale(country string) string {
 	return "sv-se"
 }
 
-func (s *PoolServer) CreateOrUpdateCheckout(host string, id cart.CartId) (*CheckoutOrder, error) {
+func (s *PoolServer) CreateOrUpdateCheckout(ctx context.Context, host string, id cart.CartId) (*CheckoutOrder, error) {
 	country := getCountryFromHost(host)
 	meta := &CheckoutMeta{
 		Terms:        fmt.Sprintf("https://%s/terms", host),
@@ -328,9 +336,9 @@ func (s *PoolServer) CreateOrUpdateCheckout(host string, id cart.CartId) (*Check
 	}
 
 	if grain.OrderReference != "" {
-		return s.klarnaClient.UpdateOrder(grain.OrderReference, bytes.NewReader(payload))
+		return s.klarnaClient.UpdateOrder(ctx, grain.OrderReference, bytes.NewReader(payload))
 	} else {
-		return s.klarnaClient.CreateOrder(bytes.NewReader(payload))
+		return s.klarnaClient.CreateOrder(ctx, bytes.NewReader(payload))
 	}
 }
 
@@ -449,18 +457,49 @@ func CartIdHandler(fn func(cartId cart.CartId, w http.ResponseWriter, r *http.Re
 func (s *PoolServer) ProxyHandler(fn func(w http.ResponseWriter, r *http.Request, cartId cart.CartId) error) func(cartId cart.CartId, w http.ResponseWriter, r *http.Request) error {
 	return func(cartId cart.CartId, w http.ResponseWriter, r *http.Request) error {
 		if ownerHost, ok := s.OwnerHost(uint64(cartId)); ok {
+			ctx, span := tracer.Start(r.Context(), "proxy")
+			defer span.End()
+			span.SetAttributes(attribute.String("cartid", cartId.String()))
+			hostAttr := attribute.String("other host", ownerHost.Name())
+			span.SetAttributes(hostAttr)
+			logger.InfoContext(ctx, "cart proxyed", "result", ownerHost.Name())
+			proxyCalls.Add(ctx, 1, metric.WithAttributes(hostAttr))
 			handled, err := ownerHost.Proxy(uint64(cartId), w, r)
+
 			grainLookups.Inc()
 			if err == nil && handled {
 				return nil
 			}
 		}
-
+		_, span := tracer.Start(r.Context(), "own")
+		span.SetAttributes(attribute.String("cartid", cartId.String()))
+		defer span.End()
 		return fn(w, r, cartId)
 
 	}
 }
 
+var (
+	tracer = otel.Tracer(name)
+
+	meter      = otel.Meter(name)
+	logger     = otelslog.NewLogger(name)
+	proxyCalls metric.Int64Counter
+
+// rollCnt metric.Int64Counter
+)
+
+func init() {
+	var err error
+	proxyCalls, err = meter.Int64Counter("proxy.calls",
+		metric.WithDescription("Number of proxy calls"),
+		metric.WithUnit("{calls}"))
+	if err != nil {
+		panic(err)
+	}
+
+}
+
 type AddVoucherRequest struct {
 	VoucherCode string `json:"code"`
 }
@@ -511,7 +550,7 @@ func (s *PoolServer) CheckoutHandler(fn func(order *CheckoutOrder, w http.Respon
 	return CookieCartIdHandler(s.ProxyHandler(func(w http.ResponseWriter, r *http.Request, cartId cart.CartId) error {
 		orderId := r.URL.Query().Get("order_id")
 		if orderId == "" {
-			order, err := s.CreateOrUpdateCheckout(r.Host, cartId)
+			order, err := s.CreateOrUpdateCheckout(r.Context(), r.Host, cartId)
 			if err != nil {
 				return err
 			}
@@ -545,46 +584,57 @@ func (s *PoolServer) RemoveVoucherHandler(w http.ResponseWriter, r *http.Request
 	return nil
 }
 
-func (s *PoolServer) Serve() *http.ServeMux {
+func (s *PoolServer) Serve(mux *http.ServeMux) {
 
-	mux := http.NewServeMux()
+	// mux.HandleFunc("OPTIONS /cart", func(w http.ResponseWriter, r *http.Request) {
-	mux.HandleFunc("OPTIONS /", func(w http.ResponseWriter, r *http.Request) {
+	// 	w.Header().Set("Access-Control-Allow-Origin", "*")
-		w.Header().Set("Access-Control-Allow-Origin", "*")
+	// 	w.Header().Set("Access-Control-Allow-Methods", "GET, PUT, POST, DELETE")
-		w.Header().Set("Access-Control-Allow-Methods", "GET, PUT, POST, DELETE")
+	// 	w.Header().Set("Access-Control-Allow-Headers", "Content-Type")
-		w.Header().Set("Access-Control-Allow-Headers", "Content-Type")
+	// 	w.WriteHeader(http.StatusOK)
-		w.WriteHeader(http.StatusOK)
+	// })
-	})
 
-	mux.HandleFunc("GET /", CookieCartIdHandler(s.ProxyHandler(s.GetCartHandler)))
+	handleFunc := func(pattern string, handlerFunc func(http.ResponseWriter, *http.Request)) {
-	mux.HandleFunc("GET /add/{sku}", CookieCartIdHandler(s.ProxyHandler(s.AddSkuToCartHandler)))
+		attr := attribute.String("http.route", pattern)
-	mux.HandleFunc("POST /add", CookieCartIdHandler(s.ProxyHandler(s.AddMultipleItemHandler)))
+		mux.HandleFunc(pattern, http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-	mux.HandleFunc("POST /", CookieCartIdHandler(s.ProxyHandler(s.AddSkuRequestHandler)))
+			span := trace.SpanFromContext(r.Context())
-	mux.HandleFunc("POST /set", CookieCartIdHandler(s.ProxyHandler(s.SetCartItemsHandler)))
+			span.SetAttributes(attr)
-	mux.HandleFunc("DELETE /{itemId}", CookieCartIdHandler(s.ProxyHandler(s.DeleteItemHandler)))
-	mux.HandleFunc("PUT /", CookieCartIdHandler(s.ProxyHandler(s.QuantityChangeHandler)))
-	mux.HandleFunc("DELETE /", CookieCartIdHandler(s.ProxyHandler(s.RemoveCartCookie)))
-	mux.HandleFunc("POST /delivery", CookieCartIdHandler(s.ProxyHandler(s.SetDeliveryHandler)))
-	mux.HandleFunc("DELETE /delivery/{deliveryId}", CookieCartIdHandler(s.ProxyHandler(s.RemoveDeliveryHandler)))
-	mux.HandleFunc("PUT /delivery/{deliveryId}/pickupPoint", CookieCartIdHandler(s.ProxyHandler(s.SetPickupPointHandler)))
-	mux.HandleFunc("PUT /voucher", CookieCartIdHandler(s.ProxyHandler(s.AddVoucherHandler)))
-	mux.HandleFunc("PUT /subscription-details", CookieCartIdHandler(s.ProxyHandler(s.SubscriptionDetailsHandler)))
-	mux.HandleFunc("DELETE /voucher/{voucherId}", CookieCartIdHandler(s.ProxyHandler(s.RemoveVoucherHandler)))
 
-	//mux.HandleFunc("GET /checkout", CookieCartIdHandler(s.ProxyHandler(s.HandleCheckout)))
+			labeler, _ := otelhttp.LabelerFromContext(r.Context())
-	//mux.HandleFunc("GET /confirmation/{orderId}", CookieCartIdHandler(s.ProxyHandler(s.HandleConfirmation)))
+			labeler.Add(attr)
+
+			handlerFunc(w, r)
+		}))
+	}
+
+	handleFunc("GET /cart", CookieCartIdHandler(s.ProxyHandler(s.GetCartHandler)))
+	handleFunc("GET /cart/add/{sku}", CookieCartIdHandler(s.ProxyHandler(s.AddSkuToCartHandler)))
+	handleFunc("POST /cart/add", CookieCartIdHandler(s.ProxyHandler(s.AddMultipleItemHandler)))
+	handleFunc("POST /cart", CookieCartIdHandler(s.ProxyHandler(s.AddSkuRequestHandler)))
+	handleFunc("POST /cart/set", CookieCartIdHandler(s.ProxyHandler(s.SetCartItemsHandler)))
+	handleFunc("DELETE /cart/{itemId}", CookieCartIdHandler(s.ProxyHandler(s.DeleteItemHandler)))
+	handleFunc("PUT /cart", CookieCartIdHandler(s.ProxyHandler(s.QuantityChangeHandler)))
+	handleFunc("DELETE /cart", CookieCartIdHandler(s.ProxyHandler(s.RemoveCartCookie)))
+	handleFunc("POST /cart/delivery", CookieCartIdHandler(s.ProxyHandler(s.SetDeliveryHandler)))
+	handleFunc("DELETE /cart/delivery/{deliveryId}", CookieCartIdHandler(s.ProxyHandler(s.RemoveDeliveryHandler)))
+	handleFunc("PUT /cart/delivery/{deliveryId}/pickupPoint", CookieCartIdHandler(s.ProxyHandler(s.SetPickupPointHandler)))
+	handleFunc("PUT /cart/voucher", CookieCartIdHandler(s.ProxyHandler(s.AddVoucherHandler)))
+	handleFunc("PUT /cart/subscription-details", CookieCartIdHandler(s.ProxyHandler(s.SubscriptionDetailsHandler)))
+	handleFunc("DELETE /cart/voucher/{voucherId}", CookieCartIdHandler(s.ProxyHandler(s.RemoveVoucherHandler)))
+
+	//mux.HandleFunc("GET /cart/checkout", CookieCartIdHandler(s.ProxyHandler(s.HandleCheckout)))
+	//mux.HandleFunc("GET /cart/confirmation/{orderId}", CookieCartIdHandler(s.ProxyHandler(s.HandleConfirmation)))
+
+	handleFunc("GET /cart/byid/{id}", CartIdHandler(s.ProxyHandler(s.GetCartHandler)))
+	handleFunc("GET /cart/byid/{id}/add/{sku}", CartIdHandler(s.ProxyHandler(s.AddSkuToCartHandler)))
+	handleFunc("POST /cart/byid/{id}", CartIdHandler(s.ProxyHandler(s.AddSkuRequestHandler)))
+	handleFunc("DELETE /cart/byid/{id}/{itemId}", CartIdHandler(s.ProxyHandler(s.DeleteItemHandler)))
+	handleFunc("PUT /cart/byid/{id}", CartIdHandler(s.ProxyHandler(s.QuantityChangeHandler)))
+	handleFunc("POST /cart/byid/{id}/delivery", CartIdHandler(s.ProxyHandler(s.SetDeliveryHandler)))
+	handleFunc("DELETE /cart/byid/{id}/delivery/{deliveryId}", CartIdHandler(s.ProxyHandler(s.RemoveDeliveryHandler)))
+	handleFunc("PUT /cart/byid/{id}/delivery/{deliveryId}/pickupPoint", CartIdHandler(s.ProxyHandler(s.SetPickupPointHandler)))
+	handleFunc("PUT /cart/byid/{id}/voucher", CookieCartIdHandler(s.ProxyHandler(s.AddVoucherHandler)))
+	handleFunc("DELETE /cart/byid/{id}/voucher/{voucherId}", CookieCartIdHandler(s.ProxyHandler(s.RemoveVoucherHandler)))
+	//mux.HandleFunc("GET /cart/byid/{id}/checkout", CartIdHandler(s.ProxyHandler(s.HandleCheckout)))
+	//mux.HandleFunc("GET /cart/byid/{id}/confirmation", CartIdHandler(s.ProxyHandler(s.HandleConfirmation)))
 
-	mux.HandleFunc("GET /byid/{id}", CartIdHandler(s.ProxyHandler(s.GetCartHandler)))
-	mux.HandleFunc("GET /byid/{id}/add/{sku}", CartIdHandler(s.ProxyHandler(s.AddSkuToCartHandler)))
-	mux.HandleFunc("POST /byid/{id}", CartIdHandler(s.ProxyHandler(s.AddSkuRequestHandler)))
-	mux.HandleFunc("DELETE /byid/{id}/{itemId}", CartIdHandler(s.ProxyHandler(s.DeleteItemHandler)))
-	mux.HandleFunc("PUT /byid/{id}", CartIdHandler(s.ProxyHandler(s.QuantityChangeHandler)))
-	mux.HandleFunc("POST /byid/{id}/delivery", CartIdHandler(s.ProxyHandler(s.SetDeliveryHandler)))
-	mux.HandleFunc("DELETE /byid/{id}/delivery/{deliveryId}", CartIdHandler(s.ProxyHandler(s.RemoveDeliveryHandler)))
-	mux.HandleFunc("PUT /byid/{id}/delivery/{deliveryId}/pickupPoint", CartIdHandler(s.ProxyHandler(s.SetPickupPointHandler)))
-	mux.HandleFunc("PUT /byid/{id}/voucher", CookieCartIdHandler(s.ProxyHandler(s.AddVoucherHandler)))
-	mux.HandleFunc("DELETE /byid/{id}/voucher/{voucherId}", CookieCartIdHandler(s.ProxyHandler(s.RemoveVoucherHandler)))
-	//mux.HandleFunc("GET /byid/{id}/checkout", CartIdHandler(s.ProxyHandler(s.HandleCheckout)))
-	//mux.HandleFunc("GET /byid/{id}/confirmation", CartIdHandler(s.ProxyHandler(s.HandleConfirmation)))
-
-	return mux
 }

cmd/cart/product-fetcher.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"context"
 	"encoding/json"
 	"fmt"
 	"net/http"
@@ -26,9 +27,14 @@ func getBaseUrl(country string) string {
 	return "http://localhost:8082"
 }
 
-func FetchItem(sku string, country string) (*index.DataItem, error) {
+func FetchItem(ctx context.Context, sku string, country string) (*index.DataItem, error) {
 	baseUrl := getBaseUrl(country)
-	res, err := http.Get(fmt.Sprintf("%s/api/by-sku/%s", baseUrl, sku))
+	req, err := http.NewRequest("GET", fmt.Sprintf("%s/api/by-sku/%s", baseUrl, sku), nil)
+	req = req.WithContext(ctx)
+	if err != nil {
+		return nil, err
+	}
+	res, err := http.DefaultClient.Do(req)
 	if err != nil {
 		return nil, err
 	}
@@ -38,8 +44,8 @@ func FetchItem(sku string, country string) (*index.DataItem, error) {
 	return &item, err
 }
 
-func GetItemAddMessage(sku string, qty int, country string, storeId *string) (*messages.AddItem, error) {
+func GetItemAddMessage(ctx context.Context, sku string, qty int, country string, storeId *string) (*messages.AddItem, error) {
-	item, err := FetchItem(sku, country)
+	item, err := FetchItem(ctx, sku, country)
 	if err != nil {
 		return nil, err
 	}

cmd/inventory/main.go

@@ -44,18 +44,25 @@ func main() {
 		s.UpdateInventory(p, "4", "4", 40)
 		return nil
 	})
-	err = s.ReserveInventory(inventory.ReserveRequest{
+	err = s.ReserveInventory(
+		inventory.ReserveRequest{
 			SKU:        "1",
 			LocationID: "1",
 			Quantity:   3,
-	}, inventory.ReserveRequest{
+		},
+		inventory.ReserveRequest{
 			SKU:        "2",
 			LocationID: "2",
 			Quantity:   15,
-	})
+		},
+		inventory.ReserveRequest{
+			SKU:        "3",
+			LocationID: "3",
+			Quantity:   25,
+		},
+	)
 	if err != nil {
 		log.Printf("Unable to reserve inventory: %v", err)
-		return
 	}
 	v, err := s.GetInventory("1", "1")
 	if err != nil {

deployment/deployment.yaml

@@ -60,14 +60,14 @@ spec:
               path: /livez
               port: web
             failureThreshold: 1
-            periodSeconds: 10
+            periodSeconds: 30
           readinessProbe:
             httpGet:
               path: /readyz
               port: web
             failureThreshold: 2
             initialDelaySeconds: 2
-            periodSeconds: 10
+            periodSeconds: 30
           volumeMounts:
             - mountPath: "/data"
               name: data
@@ -152,14 +152,14 @@ spec:
               path: /livez
               port: web
             failureThreshold: 1
-            periodSeconds: 10
+            periodSeconds: 30
           readinessProbe:
             httpGet:
               path: /readyz
               port: web
             failureThreshold: 2
             initialDelaySeconds: 2
-            periodSeconds: 10
+            periodSeconds: 50
           volumeMounts:
             - mountPath: "/data"
               name: data
@@ -177,6 +177,10 @@ spec:
                 secretKeyRef:
                   name: klarna-api-credentials
                   key: username
+            - name: OTEL_RESOURCE_ATTRIBUTES
+              value: "service.name=cart,service.version=0.1.2"
+            - name: OTEL_EXPORTER_OTLP_ENDPOINT
+              value: "http://otel-debug-service.monitoring:4317"
             - name: KLARNA_API_PASSWORD
               valueFrom:
                 secretKeyRef:
@@ -256,14 +260,14 @@ spec:
               path: /livez
               port: web
             failureThreshold: 1
-            periodSeconds: 10
+            periodSeconds: 30
           readinessProbe:
             httpGet:
               path: /readyz
               port: web
             failureThreshold: 2
             initialDelaySeconds: 2
-            periodSeconds: 10
+            periodSeconds: 30
           volumeMounts:
             - mountPath: "/data"
               name: data
@@ -276,6 +280,10 @@ spec:
           env:
             - name: TZ
               value: "Europe/Stockholm"
+            - name: OTEL_RESOURCE_ATTRIBUTES
+              value: "service.name=cart,service.version=0.1.2"
+            - name: OTEL_EXPORTER_OTLP_ENDPOINT
+              value: "http://otel-debug-service.monitoring:4317"
             - name: KLARNA_API_USERNAME
               valueFrom:
                 secretKeyRef:

go.mod

@@ -9,6 +9,18 @@ require (
 	github.com/prometheus/client_golang v1.23.2
 	github.com/rabbitmq/amqp091-go v1.10.0
 	github.com/redis/go-redis/v9 v9.16.0
+	go.opentelemetry.io/contrib/bridges/otelslog v0.13.0
+	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.63.0
+	go.opentelemetry.io/otel v1.38.0
+	go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploggrpc v0.14.0
+	go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc v1.38.0
+	go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc v1.38.0
+	go.opentelemetry.io/otel/log v0.14.0
+	go.opentelemetry.io/otel/metric v1.38.0
+	go.opentelemetry.io/otel/sdk v1.38.0
+	go.opentelemetry.io/otel/sdk/log v0.14.0
+	go.opentelemetry.io/otel/sdk/metric v1.38.0
+	go.opentelemetry.io/otel/trace v1.38.0
 	google.golang.org/grpc v1.76.0
 	google.golang.org/protobuf v1.36.10
 	k8s.io/api v0.34.1
@@ -20,14 +32,17 @@ require (
 	github.com/RoaringBitmap/roaring/v2 v2.13.0 // indirect
 	github.com/beorn7/perks v1.0.1 // indirect
 	github.com/bits-and-blooms/bitset v1.24.1 // indirect
+	github.com/cenkalti/backoff/v5 v5.0.3 // indirect
 	github.com/cespare/xxhash/v2 v2.3.0 // indirect
 	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
 	github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f // indirect
 	github.com/dprotaso/go-yit v0.0.0-20220510233725-9ba8df137936 // indirect
 	github.com/emicklei/go-restful/v3 v3.13.0 // indirect
+	github.com/felixge/httpsnoop v1.0.4 // indirect
 	github.com/fxamacker/cbor/v2 v2.9.0 // indirect
 	github.com/getkin/kin-openapi v0.132.0 // indirect
 	github.com/go-logr/logr v1.4.3 // indirect
+	github.com/go-logr/stdr v1.2.2 // indirect
 	github.com/go-openapi/jsonpointer v0.22.1 // indirect
 	github.com/go-openapi/jsonreference v0.21.2 // indirect
 	github.com/go-openapi/swag v0.25.1 // indirect
@@ -45,6 +60,7 @@ require (
 	github.com/google/gnostic-models v0.7.0 // indirect
 	github.com/google/go-cmp v0.7.0 // indirect
 	github.com/gorilla/schema v1.4.1 // indirect
+	github.com/grpc-ecosystem/grpc-gateway/v2 v2.27.2 // indirect
 	github.com/josharian/intern v1.0.0 // indirect
 	github.com/json-iterator/go v1.1.12 // indirect
 	github.com/mailru/easyjson v0.7.7 // indirect
@@ -66,6 +82,9 @@ require (
 	github.com/spf13/pflag v1.0.10 // indirect
 	github.com/vmware-labs/yaml-jsonpath v0.3.2 // indirect
 	github.com/x448/float16 v0.8.4 // indirect
+	go.opentelemetry.io/auto/sdk v1.2.1 // indirect
+	go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.38.0 // indirect
+	go.opentelemetry.io/proto/otlp v1.7.1 // indirect
 	go.yaml.in/yaml/v2 v2.4.3 // indirect
 	go.yaml.in/yaml/v3 v3.0.4 // indirect
 	golang.org/x/mod v0.29.0 // indirect
@@ -77,6 +96,7 @@ require (
 	golang.org/x/text v0.30.0 // indirect
 	golang.org/x/time v0.14.0 // indirect
 	golang.org/x/tools v0.38.0 // indirect
+	google.golang.org/genproto/googleapis/api v0.0.0-20251022142026-3a174f9686a8 // indirect
 	google.golang.org/genproto/googleapis/rpc v0.0.0-20251022142026-3a174f9686a8 // indirect
 	gopkg.in/evanphx/json-patch.v4 v4.13.0 // indirect
 	gopkg.in/inf.v0 v0.9.1 // indirect

go.sum

@@ -8,6 +8,8 @@ github.com/bsm/ginkgo/v2 v2.12.0 h1:Ny8MWAHyOepLGlLKYmXG4IEkioBysk6GpaRTLC8zwWs=
 github.com/bsm/ginkgo/v2 v2.12.0/go.mod h1:SwYbGRRDovPVboqFv0tPTcG1sN61LM1Z4ARdbAV9g4c=
 github.com/bsm/gomega v1.27.10 h1:yeMWxP2pV2fG3FgAODIY8EiRE3dy0aeFYt4l7wh6yKA=
 github.com/bsm/gomega v1.27.10/go.mod h1:JyEr/xRbxbtgWNi8tIEVPUYZ5Dzef52k01W3YH0H+O0=
+github.com/cenkalti/backoff/v5 v5.0.3 h1:ZN+IMa753KfX5hd8vVaMixjnqRZ3y8CuJKRKj1xcsSM=
+github.com/cenkalti/backoff/v5 v5.0.3/go.mod h1:rkhZdG3JZukswDf7f0cwqPNk4K0sa+F97BxZthm/crw=
 github.com/cespare/xxhash/v2 v2.3.0 h1:UL815xU9SqsFlibzuggzjXhog7bL6oX9BbNZnL2UFvs=
 github.com/cespare/xxhash/v2 v2.3.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
 github.com/chzyer/logex v1.1.10/go.mod h1:+Ywpsq7O8HXn0nuIou7OrIPyXbp3wmkHB+jjWRnGsAI=
@@ -24,6 +26,8 @@ github.com/dprotaso/go-yit v0.0.0-20220510233725-9ba8df137936 h1:PRxIJD8XjimM5aT
 github.com/dprotaso/go-yit v0.0.0-20220510233725-9ba8df137936/go.mod h1:ttYvX5qlB+mlV1okblJqcSMtR4c52UKxDiX9GRBS8+Q=
 github.com/emicklei/go-restful/v3 v3.13.0 h1:C4Bl2xDndpU6nJ4bc1jXd+uTmYPVUwkD6bFY/oTyCes=
 github.com/emicklei/go-restful/v3 v3.13.0/go.mod h1:6n3XBCmQQb25CM2LCACGz8ukIrRry+4bhvbpWn3mrbc=
+github.com/felixge/httpsnoop v1.0.4 h1:NFTV2Zj1bL4mc9sqWACXbQFVBBg2W3GPvqp8/ESS2Wg=
+github.com/felixge/httpsnoop v1.0.4/go.mod h1:m8KPJKqk1gH5J9DgRY2ASl2lWCfGKXixSwevea8zH2U=
 github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
 github.com/fsnotify/fsnotify v1.4.9 h1:hsms1Qyu0jgnwNXIxa+/V/PDsU6CfLf6CNO8H7IWoS4=
 github.com/fsnotify/fsnotify v1.4.9/go.mod h1:znqG4EE+3YCdAaPaxE2ZRY/06pZUdp0tY4IgpuI1SZQ=
@@ -31,6 +35,7 @@ github.com/fxamacker/cbor/v2 v2.9.0 h1:NpKPmjDBgUfBms6tr6JZkTHtfFGcMKsw3eGcmD/sa
 github.com/fxamacker/cbor/v2 v2.9.0/go.mod h1:vM4b+DJCtHn+zz7h3FFp/hDAI9WNWCsZj23V5ytsSxQ=
 github.com/getkin/kin-openapi v0.132.0 h1:3ISeLMsQzcb5v26yeJrBcdTCEQTag36ZjaGk7MIRUwk=
 github.com/getkin/kin-openapi v0.132.0/go.mod h1:3OlG51PCYNsPByuiMB0t4fjnNlIDnaEDsjiKUV8nL58=
+github.com/go-logr/logr v1.2.2/go.mod h1:jdQByPbusPIv2/zmleS9BjJVeZ6kBagPoEUsqbVz/1A=
 github.com/go-logr/logr v1.4.3 h1:CjnDlHq8ikf6E492q6eKboGOC0T8CDaOvkHCIg8idEI=
 github.com/go-logr/logr v1.4.3/go.mod h1:9T104GzyrTigFIr8wt5mBrctHMim0Nb2HLGrmQ40KvY=
 github.com/go-logr/stdr v1.2.2 h1:hSWxHoqTgW2S2qGc0LTAI563KZ5YKYRhT3MFKZMbjag=
@@ -100,6 +105,8 @@ github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
 github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/gorilla/schema v1.4.1 h1:jUg5hUjCSDZpNGLuXQOgIWGdlgrIdYvgQ0wZtdK1M3E=
 github.com/gorilla/schema v1.4.1/go.mod h1:Dg5SSm5PV60mhF2NFaTV1xuYYj8tV8NOPRo4FggUMnM=
+github.com/grpc-ecosystem/grpc-gateway/v2 v2.27.2 h1:8Tjv8EJ+pM1xP8mK6egEbD1OgnVTyacbefKhmbLhIhU=
+github.com/grpc-ecosystem/grpc-gateway/v2 v2.27.2/go.mod h1:pkJQ2tZHJ0aFOVEEot6oZmaVEZcRme73eIFmhiVuRWs=
 github.com/hpcloud/tail v1.0.0/go.mod h1:ab1qPbhIpdTxEkNHXyeSf5vhxWSCs/tWer42PpOxQnU=
 github.com/ianlancetaylor/demangle v0.0.0-20200824232613-28f6c0f3b639/go.mod h1:aSSvb/t6k1mPoxDqO4vJh6VOCGPwU4O0C2/Eqndh1Sc=
 github.com/josharian/intern v1.0.0 h1:vlS4z54oSdjm0bgjRigI+G1HpF+tI+9rE5LLzOg8HmY=
@@ -176,8 +183,8 @@ github.com/rabbitmq/amqp091-go v1.10.0 h1:STpn5XsHlHGcecLmMFCtg7mqq0RnD+zFr4uzuk
 github.com/rabbitmq/amqp091-go v1.10.0/go.mod h1:Hy4jKW5kQART1u+JkDTF9YYOQUHXqMuhrgxOEeS7G4o=
 github.com/redis/go-redis/v9 v9.16.0 h1:OotgqgLSRCmzfqChbQyG1PHC3tLNR89DG4jdOERSEP4=
 github.com/redis/go-redis/v9 v9.16.0/go.mod h1:u410H11HMLoB+TP67dz8rL9s6QW2j76l0//kSOd3370=
-github.com/rogpeppe/go-internal v1.13.1 h1:KvO1DLK/DRN07sQ1LQKScxyZJuNnedQ5/wKSR38lUII=
+github.com/rogpeppe/go-internal v1.14.1 h1:UQB4HGPB6osV0SQTLymcB4TgvyWu6ZyliaW0tI/otEQ=
-github.com/rogpeppe/go-internal v1.13.1/go.mod h1:uMEvuHeurkdAXX61udpOXGD/AzZDWNMNyH2VO9fmH0o=
+github.com/rogpeppe/go-internal v1.14.1/go.mod h1:MaRKkUm5W0goXpeCfT7UZI6fk/L7L7so1lCWt35ZSgc=
 github.com/sergi/go-diff v1.1.0 h1:we8PVUC3FE2uYfodKH/nBHMSetSfHDR6scGdBi+erh0=
 github.com/sergi/go-diff v1.1.0/go.mod h1:STckp+ISIX8hZLjrqAeVduY0gWCT9IjLuqbuNXdaHfM=
 github.com/speakeasy-api/jsonpath v0.6.0 h1:IhtFOV9EbXplhyRqsVhHoBmmYjblIRh5D1/g8DHMXJ8=
@@ -204,16 +211,36 @@ github.com/yuin/goldmark v1.1.27/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9de
 github.com/yuin/goldmark v1.2.1/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
 go.opentelemetry.io/auto/sdk v1.2.1 h1:jXsnJ4Lmnqd11kwkBV2LgLoFMZKizbCi5fNZ/ipaZ64=
 go.opentelemetry.io/auto/sdk v1.2.1/go.mod h1:KRTj+aOaElaLi+wW1kO/DZRXwkF4C5xPbEe3ZiIhN7Y=
+go.opentelemetry.io/contrib/bridges/otelslog v0.13.0 h1:bwnLpizECbPr1RrQ27waeY2SPIPeccCx/xLuoYADZ9s=
+go.opentelemetry.io/contrib/bridges/otelslog v0.13.0/go.mod h1:3nWlOiiqA9UtUnrcNk82mYasNxD8ehOspL0gOfEo6Y4=
+go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.63.0 h1:RbKq8BG0FI8OiXhBfcRtqqHcZcka+gU3cskNuf05R18=
+go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.63.0/go.mod h1:h06DGIukJOevXaj/xrNjhi/2098RZzcLTbc0jDAUbsg=
 go.opentelemetry.io/otel v1.38.0 h1:RkfdswUDRimDg0m2Az18RKOsnI8UDzppJAtj01/Ymk8=
 go.opentelemetry.io/otel v1.38.0/go.mod h1:zcmtmQ1+YmQM9wrNsTGV/q/uyusom3P8RxwExxkZhjM=
+go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploggrpc v0.14.0 h1:OMqPldHt79PqWKOMYIAQs3CxAi7RLgPxwfFSwr4ZxtM=
+go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploggrpc v0.14.0/go.mod h1:1biG4qiqTxKiUCtoWDPpL3fB3KxVwCiGw81j3nKMuHE=
+go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc v1.38.0 h1:vl9obrcoWVKp/lwl8tRE33853I8Xru9HFbw/skNeLs8=
+go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc v1.38.0/go.mod h1:GAXRxmLJcVM3u22IjTg74zWBrRCKq8BnOqUVLodpcpw=
+go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.38.0 h1:GqRJVj7UmLjCVyVJ3ZFLdPRmhDUp2zFmQe3RHIOsw24=
+go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.38.0/go.mod h1:ri3aaHSmCTVYu2AWv44YMauwAQc0aqI9gHKIcSbI1pU=
+go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc v1.38.0 h1:lwI4Dc5leUqENgGuQImwLo4WnuXFPetmPpkLi2IrX54=
+go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc v1.38.0/go.mod h1:Kz/oCE7z5wuyhPxsXDuaPteSWqjSBD5YaSdbxZYGbGk=
+go.opentelemetry.io/otel/log v0.14.0 h1:2rzJ+pOAZ8qmZ3DDHg73NEKzSZkhkGIua9gXtxNGgrM=
+go.opentelemetry.io/otel/log v0.14.0/go.mod h1:5jRG92fEAgx0SU/vFPxmJvhIuDU9E1SUnEQrMlJpOno=
 go.opentelemetry.io/otel/metric v1.38.0 h1:Kl6lzIYGAh5M159u9NgiRkmoMKjvbsKtYRwgfrA6WpA=
 go.opentelemetry.io/otel/metric v1.38.0/go.mod h1:kB5n/QoRM8YwmUahxvI3bO34eVtQf2i4utNVLr9gEmI=
 go.opentelemetry.io/otel/sdk v1.38.0 h1:l48sr5YbNf2hpCUj/FoGhW9yDkl+Ma+LrVl8qaM5b+E=
 go.opentelemetry.io/otel/sdk v1.38.0/go.mod h1:ghmNdGlVemJI3+ZB5iDEuk4bWA3GkTpW+DOoZMYBVVg=
+go.opentelemetry.io/otel/sdk/log v0.14.0 h1:JU/U3O7N6fsAXj0+CXz21Czg532dW2V4gG1HE/e8Zrg=
+go.opentelemetry.io/otel/sdk/log v0.14.0/go.mod h1:imQvII+0ZylXfKU7/wtOND8Hn4OpT3YUoIgqJVksUkM=
+go.opentelemetry.io/otel/sdk/log/logtest v0.14.0 h1:Ijbtz+JKXl8T2MngiwqBlPaHqc4YCaP/i13Qrow6gAM=
+go.opentelemetry.io/otel/sdk/log/logtest v0.14.0/go.mod h1:dCU8aEL6q+L9cYTqcVOk8rM9Tp8WdnHOPLiBgp0SGOA=
 go.opentelemetry.io/otel/sdk/metric v1.38.0 h1:aSH66iL0aZqo//xXzQLYozmWrXxyFkBJ6qT5wthqPoM=
 go.opentelemetry.io/otel/sdk/metric v1.38.0/go.mod h1:dg9PBnW9XdQ1Hd6ZnRz689CbtrUp0wMMs9iPcgT9EZA=
 go.opentelemetry.io/otel/trace v1.38.0 h1:Fxk5bKrDZJUH+AMyyIXGcFAPah0oRcT+LuNtJrmcNLE=
 go.opentelemetry.io/otel/trace v1.38.0/go.mod h1:j1P9ivuFsTceSWe1oY+EeW3sc+Pp42sO++GHkg4wwhs=
+go.opentelemetry.io/proto/otlp v1.7.1 h1:gTOMpGDb0WTBOP8JaO72iL3auEZhVmAQg4ipjOVAtj4=
+go.opentelemetry.io/proto/otlp v1.7.1/go.mod h1:b2rVh6rfI/s2pHWNlB7ILJcRALpcNDzKhACevjI+ZnE=
 go.uber.org/goleak v1.3.0 h1:2K3zAYmnTNqV73imy9J1T3WC+gmCePx2hEGkimedGto=
 go.uber.org/goleak v1.3.0/go.mod h1:CoHD4mav9JJNrW/WLlf7HGZPjdw8EucARQHekz1X6bE=
 go.yaml.in/yaml/v2 v2.4.3 h1:6gvOSjQoTB3vt1l+CU+tSyi/HOjfOjRLJ4YwYZGwRO0=
@@ -286,6 +313,8 @@ golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8T
 golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 gonum.org/v1/gonum v0.16.0 h1:5+ul4Swaf3ESvrOnidPp4GZbzf0mxVQpDCYUQE7OJfk=
 gonum.org/v1/gonum v0.16.0/go.mod h1:fef3am4MQ93R2HHpKnLk4/Tbh/s0+wqD5nfa6Pnwy4E=
+google.golang.org/genproto/googleapis/api v0.0.0-20251022142026-3a174f9686a8 h1:mepRgnBZa07I4TRuomDE4sTIYieg/osKmzIf4USdWS4=
+google.golang.org/genproto/googleapis/api v0.0.0-20251022142026-3a174f9686a8/go.mod h1:fDMmzKV90WSg1NbozdqrE64fkuTv6mlq2zxo9ad+3yo=
 google.golang.org/genproto/googleapis/rpc v0.0.0-20251022142026-3a174f9686a8 h1:M1rk8KBnUsBDg1oPGHNCxG4vc1f49epmTO7xscSajMk=
 google.golang.org/genproto/googleapis/rpc v0.0.0-20251022142026-3a174f9686a8/go.mod h1:7i2o+ce6H/6BluujYR+kqX3GKH+dChPTQU19wjRPiGk=
 google.golang.org/grpc v1.76.0 h1:UnVkv1+uMLYXoIz6o7chp59WfQUYA2ex/BXQ9rHZu7A=

pkg/actor/grpc_server.go

@@ -8,6 +8,10 @@ import (
 	"time"
 
 	messages "git.tornberg.me/go-cart-actor/pkg/messages"
+	"go.opentelemetry.io/contrib/bridges/otelslog"
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/metric"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/reflection"
 )
@@ -19,9 +23,74 @@ type ControlServer[V any] struct {
 	pool GrainPool[V]
 }
 
+const name = "grpc_server"
+
+var (
+	tracer                 = otel.Tracer(name)
+	meter                  = otel.Meter(name)
+	logger                 = otelslog.NewLogger(name)
+	pingCalls              metric.Int64Counter
+	negotiateCalls         metric.Int64Counter
+	getLocalActorIdsCalls  metric.Int64Counter
+	announceOwnershipCalls metric.Int64Counter
+	announceExpiryCalls    metric.Int64Counter
+	closingCalls           metric.Int64Counter
+)
+
+func init() {
+	var err error
+	pingCalls, err = meter.Int64Counter("grpc.ping_calls",
+		metric.WithDescription("Number of ping calls"),
+		metric.WithUnit("{calls}"))
+	if err != nil {
+		panic(err)
+	}
+	negotiateCalls, err = meter.Int64Counter("grpc.negotiate_calls",
+		metric.WithDescription("Number of negotiate calls"),
+		metric.WithUnit("{calls}"))
+	if err != nil {
+		panic(err)
+	}
+	getLocalActorIdsCalls, err = meter.Int64Counter("grpc.get_local_actor_ids_calls",
+		metric.WithDescription("Number of get local actor ids calls"),
+		metric.WithUnit("{calls}"))
+	if err != nil {
+		panic(err)
+	}
+	announceOwnershipCalls, err = meter.Int64Counter("grpc.announce_ownership_calls",
+		metric.WithDescription("Number of announce ownership calls"),
+		metric.WithUnit("{calls}"))
+	if err != nil {
+		panic(err)
+	}
+	announceExpiryCalls, err = meter.Int64Counter("grpc.announce_expiry_calls",
+		metric.WithDescription("Number of announce expiry calls"),
+		metric.WithUnit("{calls}"))
+	if err != nil {
+		panic(err)
+	}
+	closingCalls, err = meter.Int64Counter("grpc.closing_calls",
+		metric.WithDescription("Number of closing calls"),
+		metric.WithUnit("{calls}"))
+	if err != nil {
+		panic(err)
+	}
+}
+
 func (s *ControlServer[V]) AnnounceOwnership(ctx context.Context, req *messages.OwnershipAnnounce) (*messages.OwnerChangeAck, error) {
+	ctx, span := tracer.Start(ctx, "grpc_announce_ownership")
+	defer span.End()
+	span.SetAttributes(
+		attribute.String("component", "controlplane"),
+		attribute.String("host", req.Host),
+		attribute.Int("id_count", len(req.Ids)),
+	)
+	logger.InfoContext(ctx, "announce ownership", "host", req.Host, "id_count", len(req.Ids))
+	announceOwnershipCalls.Add(ctx, 1, metric.WithAttributes(attribute.String("host", req.Host)))
+
 	err := s.pool.HandleOwnershipChange(req.Host, req.Ids)
 	if err != nil {
+		span.RecordError(err)
 		return &messages.OwnerChangeAck{
 			Accepted: false,
 			Message:  "owner change failed",
@@ -36,7 +105,20 @@ func (s *ControlServer[V]) AnnounceOwnership(ctx context.Context, req *messages.
 }
 
 func (s *ControlServer[V]) AnnounceExpiry(ctx context.Context, req *messages.ExpiryAnnounce) (*messages.OwnerChangeAck, error) {
+	ctx, span := tracer.Start(ctx, "grpc_announce_expiry")
+	defer span.End()
+	span.SetAttributes(
+		attribute.String("component", "controlplane"),
+		attribute.String("host", req.Host),
+		attribute.Int("id_count", len(req.Ids)),
+	)
+	logger.InfoContext(ctx, "announce expiry", "host", req.Host, "id_count", len(req.Ids))
+	announceExpiryCalls.Add(ctx, 1, metric.WithAttributes(attribute.String("host", req.Host)))
+
 	err := s.pool.HandleRemoteExpiry(req.Host, req.Ids)
+	if err != nil {
+		span.RecordError(err)
+	}
 	return &messages.OwnerChangeAck{
 		Accepted: err == nil,
 		Message:  "expiry acknowledged",
@@ -45,15 +127,28 @@ func (s *ControlServer[V]) AnnounceExpiry(ctx context.Context, req *messages.Exp
 
 // ControlPlane: Ping
 func (s *ControlServer[V]) Ping(ctx context.Context, _ *messages.Empty) (*messages.PingReply, error) {
+
+	host := s.pool.Hostname()
+
+	pingCalls.Add(ctx, 1, metric.WithAttributes(attribute.String("host", host)))
+
 	// log.Printf("got ping")
 	return &messages.PingReply{
-		Host:     s.pool.Hostname(),
+		Host:     host,
 		UnixTime: time.Now().Unix(),
 	}, nil
 }
 
 // ControlPlane: Negotiate (merge host views)
 func (s *ControlServer[V]) Negotiate(ctx context.Context, req *messages.NegotiateRequest) (*messages.NegotiateReply, error) {
+	ctx, span := tracer.Start(ctx, "grpc_negotiate")
+	defer span.End()
+	span.SetAttributes(
+		attribute.String("component", "controlplane"),
+		attribute.Int("known_hosts_count", len(req.KnownHosts)),
+	)
+	logger.InfoContext(ctx, "negotiate", "known_hosts_count", len(req.KnownHosts))
+	negotiateCalls.Add(ctx, 1)
 
 	s.pool.Negotiate(req.KnownHosts)
 	return &messages.NegotiateReply{Hosts: req.GetKnownHosts()}, nil
@@ -61,13 +156,33 @@ func (s *ControlServer[V]) Negotiate(ctx context.Context, req *messages.Negotiat
 
 // ControlPlane: GetCartIds (locally owned carts only)
 func (s *ControlServer[V]) GetLocalActorIds(ctx context.Context, _ *messages.Empty) (*messages.ActorIdsReply, error) {
-	return &messages.ActorIdsReply{Ids: s.pool.GetLocalIds()}, nil
+	ctx, span := tracer.Start(ctx, "grpc_get_local_actor_ids")
+	defer span.End()
+	ids := s.pool.GetLocalIds()
+	span.SetAttributes(
+		attribute.String("component", "controlplane"),
+		attribute.Int("id_count", len(ids)),
+	)
+	logger.InfoContext(ctx, "get local actor ids", "id_count", len(ids))
+	getLocalActorIdsCalls.Add(ctx, 1)
+
+	return &messages.ActorIdsReply{Ids: ids}, nil
 }
 
 // ControlPlane: Closing (peer shutdown notification)
 func (s *ControlServer[V]) Closing(ctx context.Context, req *messages.ClosingNotice) (*messages.OwnerChangeAck, error) {
-	if req.GetHost() != "" {
+	ctx, span := tracer.Start(ctx, "grpc_closing")
-		s.pool.RemoveHost(req.GetHost())
+	defer span.End()
+	host := req.GetHost()
+	span.SetAttributes(
+		attribute.String("component", "controlplane"),
+		attribute.String("host", host),
+	)
+	logger.InfoContext(ctx, "closing notice", "host", host)
+	closingCalls.Add(ctx, 1, metric.WithAttributes(attribute.String("host", host)))
+
+	if host != "" {
+		s.pool.RemoveHost(host)
 	}
 	return &messages.OwnerChangeAck{
 		Accepted: true,

pkg/inventory/redis_service.go

@@ -88,20 +88,50 @@ var (
 	ErrMissingReservation    = errors.New("missing reservation")
 )
 
+func makeKeysAndArgs(req ...ReserveRequest) ([]string, []string) {
+	keys := make([]string, len(req))
+	args := make([]string, len(req))
+	for i, r := range req {
+		if r.Quantity <= 0 {
+			return nil, nil
+		}
+		keys[i] = getInventoryKey(r.SKU, r.LocationID)
+		args[i] = strconv.Itoa(int(r.Quantity))
+	}
+	return keys, args
+}
+
+func (s *RedisInventoryService) ReservationCheck(req ...ReserveRequest) error {
+	if len(req) == 0 {
+		return ErrMissingReservation
+	}
+
+	keys, args := makeKeysAndArgs(req...)
+	if keys == nil || args == nil {
+		return ErrInvalidQuantity
+	}
+
+	cmd := reservationCheck.Run(s.ctx, s.client, keys, args)
+	if err := cmd.Err(); err != nil {
+		return err
+	}
+	if val, err := cmd.Int(); err != nil {
+		return err
+	} else if val != 1 {
+		return ErrInsufficientInventory
+	}
+	return nil
+}
+
 func (s *RedisInventoryService) ReserveInventory(req ...ReserveRequest) error {
 	if len(req) == 0 {
 		return ErrMissingReservation
 	}
 
-	keys := make([]string, len(req))
+	keys, args := makeKeysAndArgs(req...)
-	args := make([]string, len(req))
+	if keys == nil || args == nil {
-	for i, r := range req {
-		if r.Quantity <= 0 {
 		return ErrInvalidQuantity
 	}
-		keys[i] = getInventoryKey(r.SKU, r.LocationID)
-		args[i] = strconv.Itoa(int(r.Quantity))
-	}
 	cmd := reserveScript.Run(s.ctx, s.client, keys, args)
 	if err := cmd.Err(); err != nil {
 		return err
@@ -114,6 +144,47 @@ func (s *RedisInventoryService) ReserveInventory(req ...ReserveRequest) error {
 	return nil
 }
 
+var reservationCheck = redis.NewScript(`
+-- Get the number of keys passed
+local num_keys = #KEYS
+
+-- Ensure the number of keys matches the number of quantities
+if num_keys ~= #ARGV then
+  return {err = "Script requires the same number of keys and quantities."}
+end
+
+local new_values = {}
+local payload = {}
+
+-- ---
+-- 1. CHECK PHASE
+-- ---
+-- Loop through all keys to check their values first
+for i = 1, num_keys do
+  local key = KEYS[i]
+  local quantity_to_check = tonumber(ARGV[i])
+
+  -- Fail if the quantity is not a valid number
+  if not quantity_to_check then
+    return {err = "Invalid quantity provided for key: " .. key}
+  end
+
+  -- Get the current value stored at the key
+  local current_val = tonumber(redis.call('GET', key))
+
+  -- Check the condition
+  -- Fail if:
+  -- 1. The key doesn't exist (current_val is nil)
+  -- 2. The value is not > the required quantity
+  if not current_val or current_val <= quantity_to_check then
+    -- Return 0 to indicate the operation failed and no changes were made
+    return 0
+  end
+end
+
+return 1
+`)
+
 var reserveScript = redis.NewScript(`
 -- Get the number of keys passed
 local num_keys = #KEYS

pkg/proxy/remotehost.go

@@ -10,6 +10,9 @@ import (
 	"time"
 
 	messages "git.tornberg.me/go-cart-actor/pkg/messages"
+	"go.opentelemetry.io/contrib/bridges/otelslog"
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/attribute"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/credentials/insecure"
 )
@@ -26,6 +29,14 @@ type RemoteHost struct {
 	missedPings   int
 }
 
+const name = "proxy"
+
+var (
+	tracer = otel.Tracer(name)
+	meter  = otel.Meter(name)
+	logger = otelslog.NewLogger(name)
+)
+
 func NewRemoteHost(host string) (*RemoteHost, error) {
 
 	target := fmt.Sprintf("%s:1337", host)
@@ -49,7 +60,7 @@ func NewRemoteHost(host string) (*RemoteHost, error) {
 
 	return &RemoteHost{
 		host:          host,
-		httpBase:      fmt.Sprintf("http://%s:8080/cart", host),
+		httpBase:      fmt.Sprintf("http://%s:8080", host),
 		conn:          conn,
 		transport:     transport,
 		client:        client,
@@ -146,8 +157,22 @@ func (h *RemoteHost) AnnounceExpiry(uids []uint64) {
 func (h *RemoteHost) Proxy(id uint64, w http.ResponseWriter, r *http.Request) (bool, error) {
 	target := fmt.Sprintf("%s%s", h.httpBase, r.URL.RequestURI())
 
-	req, err := http.NewRequestWithContext(r.Context(), r.Method, target, r.Body)
+	log.Printf("proxy target: %s, method: %s", target, r.Method)
+
+	ctx, span := tracer.Start(r.Context(), "remote_proxy")
+	defer span.End()
+	span.SetAttributes(
+		attribute.String("component", "proxy"),
+		attribute.String("cartid", fmt.Sprintf("%d", id)),
+		attribute.String("host", h.host),
+		attribute.String("method", r.Method),
+		attribute.String("target", target),
+	)
+	logger.InfoContext(ctx, "proxying request", "cartid", id, "host", h.host, "method", r.Method)
+
+	req, err := http.NewRequestWithContext(ctx, r.Method, target, r.Body)
 	if err != nil {
+		span.RecordError(err)
 		http.Error(w, "proxy build error", http.StatusBadGateway)
 		return false, err
 	}
@@ -161,10 +186,12 @@ func (h *RemoteHost) Proxy(id uint64, w http.ResponseWriter, r *http.Request) (b
 	}
 	res, err := h.client.Do(req)
 	if err != nil {
+		span.RecordError(err)
 		http.Error(w, "proxy request error", http.StatusBadGateway)
 		return false, err
 	}
 	defer res.Body.Close()
+	span.SetAttributes(attribute.Int("status_code", res.StatusCode))
 	for k, v := range res.Header {
 		for _, vv := range v {
 			w.Header().Add(k, vv)
@@ -175,6 +202,7 @@ func (h *RemoteHost) Proxy(id uint64, w http.ResponseWriter, r *http.Request) (b
 	w.WriteHeader(res.StatusCode)
 	_, copyErr := io.Copy(w, res.Body)
 	if copyErr != nil {
+		span.RecordError(copyErr)
 		return true, copyErr
 	}
 	return true, nil