make otel generator actually generate traces

observability/otelgen/main.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"os/signal"
 	"syscall"
+	"time"
 
 	"go.opentelemetry.io/otel"
 	"go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc"
@@ -13,19 +14,40 @@ import (
 	sdktrace "go.opentelemetry.io/otel/sdk/trace"
 )
 
+var (
+	tracer = otel.Tracer("otelgen")
+)
+
 func main() {
 	ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)
 	defer stop()
 
 	res := makeResource(ctx)
-	shutdown := initOpenTelemetry(ctx, res, "http://localhost:4317")
+	shutdown := initOpenTelemetry(ctx, res, "localhost:4317")
+
+	ticker := time.NewTicker(10 * time.Second)
+
+loop:
+	for {
+		select {
+		case <-ctx.Done():
+			shutdown(context.TODO())
+			break loop
+		case <-ticker.C:
+			genSpan(ctx)
+		}
+	}
+}
+
+func genSpan(ctx context.Context) {
+	ctx, span := tracer.Start(ctx, "generate")
+	defer span.End()
 
-	<-ctx.Done()
-	shutdown(context.TODO())
+	span.AddEvent("example span event")
 }
 
 func initOpenTelemetry(ctx context.Context, res *resource.Resource, endpoint string) func(ctx context.Context) error {
-	exporter, err := otlptracegrpc.New(ctx, otlptracegrpc.WithEndpoint(endpoint))
+	exporter, err := otlptracegrpc.New(ctx, otlptracegrpc.WithEndpoint(endpoint), otlptracegrpc.WithInsecure())
 	if err != nil {
 		panic(fmt.Errorf("failed to create OTLP exporter: %w", err))
 	}