metrics

cmd/checkout/main.go

@@ -21,17 +21,16 @@ import (
 	"git.k6n.net/mats/platform/tax"
 	"github.com/adyen/adyen-go-api-library/v21/src/adyen"
 	"github.com/adyen/adyen-go-api-library/v21/src/common"
-	"github.com/prometheus/client_golang/prometheus"
-	"github.com/prometheus/client_golang/prometheus/promauto"
 	"github.com/redis/go-redis/v9"
 	"go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"
 )
 
 var (
-	grainSpawns = promauto.NewCounter(prometheus.CounterOpts{
-		Name: "checkout_grain_spawned_total",
-		Help: "The total number of spawned checkout grains",
-	})
+	// checkoutMetrics is the shared prometheus instrumentation for the
+	// checkout actor pool and event log. Built once at process start;
+	// the actor package's touch sites are nil-safe so a test binary
+	// could pass nil.
+	checkoutMetrics = actor.NewMetrics("checkout")
 )
 
 func init() {
@@ -114,14 +113,15 @@ func main() {
 		checkoutDir = "data"
 	}
 	diskStorage := actor.NewDiskStorage[checkout.CheckoutGrain](checkoutDir, reg)
+	diskStorage.SetMetrics(checkoutMetrics)
 	var syncedServer *CheckoutPoolServer
 	poolConfig := actor.GrainPoolConfig[checkout.CheckoutGrain]{
 		MutationRegistry: reg,
 		Storage:          diskStorage,
+		Metrics:          checkoutMetrics,
 		Spawn: func(ctx context.Context, id uint64) (actor.Grain[checkout.CheckoutGrain], error) {
 			_, span := tracer.Start(ctx, fmt.Sprintf("Spawn checkout id %d", id))
 			defer span.End()
-			grainSpawns.Inc()
 
 			ret := checkout.NewCheckoutGrain(id, 0, 0, time.Now(), nil) // version to be set later
 			// Load persisted events/state for this checkout if present