First draft. One metric - command duration.

Signed-off-by: Elena Kolevska <elena@kolevska.com>

example/otel_metrics.go

@@ -0,0 +1,88 @@
+// EXAMPLE: otel_metrics
+// HIDE_START
+package main
+
+import (
+	"context"
+	"log"
+	"strconv"
+	"time"
+
+	redisotel "github.com/redis/go-redis/extra/redisotel-native/v9"
+	"github.com/redis/go-redis/v9"
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc"
+	"go.opentelemetry.io/otel/sdk/metric"
+)
+
+// ExampleClient_otel_metrics demonstrates how to enable OpenTelemetry metrics
+// for Redis operations and export them to an OTLP collector.
+func main() {
+	ctx := context.Background()
+
+	// HIDE_END
+
+	// STEP_START otel_exporter_setup
+	// Create OTLP exporter that sends metrics to the collector
+	// Default endpoint is localhost:4317 (gRPC)
+	exporter, err := otlpmetricgrpc.New(ctx,
+		otlpmetricgrpc.WithInsecure(), // Use insecure for local development
+		// For production, configure TLS and authentication:
+		// otlpmetricgrpc.WithEndpoint("your-collector:4317"),
+		// otlpmetricgrpc.WithTLSCredentials(...),
+	)
+	if err != nil {
+		log.Fatalf("Failed to create OTLP exporter: %v", err)
+	}
+	// STEP_END
+
+	// STEP_START otel_meter_provider
+	// Create meter provider with periodic reader
+	// Metrics are exported every 10 seconds
+	meterProvider := metric.NewMeterProvider(
+		metric.WithReader(
+			metric.NewPeriodicReader(exporter,
+				metric.WithInterval(10*time.Second),
+			),
+		),
+	)
+	defer func() {
+		if err := meterProvider.Shutdown(ctx); err != nil {
+			log.Printf("Error shutting down meter provider: %v", err)
+		}
+	}()
+
+	// Set the global meter provider
+	otel.SetMeterProvider(meterProvider)
+	// STEP_END
+
+	// STEP_START redis_client_setup
+	// Create Redis client
+	rdb := redis.NewClient(&redis.Options{
+		Addr: "localhost:6379",
+	})
+	defer rdb.Close()
+
+	// Initialize OTel instrumentation (uses global meter provider)
+	if err := redisotel.Init(rdb); err != nil {
+		log.Fatalf("Failed to initialize OTel: %v", err)
+	}
+	defer redisotel.Shutdown()
+	// STEP_END
+
+	// STEP_START redis_operations
+	// Execute Redis operations - metrics are automatically collected
+	log.Println("Executing Redis operations...")
+	for i := range 100 {
+		if err := rdb.Set(ctx, "key"+strconv.Itoa(i), "value", 0).Err(); err != nil {
+			log.Printf("Error setting key: %v", err)
+		}
+		time.Sleep(time.Millisecond * 100)
+	}
+	log.Println("Operations complete. Waiting for metrics to be exported...")
+
+	// Wait for metrics to be exported
+	time.Sleep(15 * time.Second)
+	// STEP_END
+}
+