adds OpenTelemetry startup tracing, updates Go dependencies, and refines build configurations

main.go

@@ -19,16 +19,23 @@ import (
 	"time"
 
 	"github.com/rs/zerolog"
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/codes"
+	"go.opentelemetry.io/otel/trace"
 	"golang.org/x/sys/unix"
 
 	"gitea.libretechconsulting.com/rmcguire/go-app/pkg/app"
+	"gitea.libretechconsulting.com/rmcguire/go-app/pkg/otel"
 
 	"gitea.libretechconsulting.com/rmcguire/go-server-with-otel/pkg/config"
 	"gitea.libretechconsulting.com/rmcguire/go-server-with-otel/pkg/demo"
 	"gitea.libretechconsulting.com/rmcguire/go-server-with-otel/pkg/service"
 )
 
-const terminationGracePeriod = 30 * time.Second
+const (
+	terminationGracePeriod = 30 * time.Second
+	appName                = "demo-app"
+)
 
 var (
 	// TODO: Register your service.AppService implementers here
@@ -51,14 +58,24 @@ func main() {
 	// app config struct which embeds app.AooConfig
 	ctx, serviceConfig := app.MustLoadConfigInto(ctx, &config.ServiceConfig{})
 
-	log := zerolog.Ctx(ctx)
-
 	// Print schema if that's all we have to do
 	if flagSchema {
 		printSchema()
 		os.Exit(1)
 	}
 
+	// Prepare app
+	app := &app.App{
+		AppContext: ctx,
+	}
+	app.InitOTEL()
+
+	tracer := otel.GetTracer(ctx, appName)
+	ctx, span := tracer.Start(ctx, appName+".startup", trace.WithAttributes(
+		attribute.Int("appServices", len(appServices)),
+	))
+
+	log := zerolog.Ctx(ctx)
 	log.Debug().Any("mergedConfig", serviceConfig).Msg("App configuration prepared")
 
 	// Prepare services
@@ -67,23 +84,25 @@ func main() {
 	for i, svc := range appServices {
 		sdFuncs[i], err = svc.Init(ctx, serviceConfig)
 		if err != nil {
+			span.RecordError(err)
+			span.SetStatus(codes.Error, err.Error())
 			log.Fatal().Err(err).Send()
 		}
 	}
+	span.AddEvent("app services initialized")
 
-	// Merge all service implementations for app
+	// Merge all service implementations and add to app
 	grpcSvcs, httpSvcs := service.MergeServices(ctx, appServices...)
-
-	// Prepare app with all merged services
-	app := &app.App{
-		AppContext: ctx,
-		GRPC:       grpcSvcs,
-		HTTP:       httpSvcs,
-	}
+	app.GRPC = grpcSvcs
+	app.HTTP = httpSvcs
 
 	// Launch app
 	app.MustRun()
 
+	span.AddEvent("app started")
+	span.SetStatus(codes.Ok, "")
+	span.End()
+
 	// Wait for app to complete and then perform internal shutdown
 	<-app.Done()