feat: fix graceful shutdown, add config validation

config/config.go

@@ -135,3 +135,35 @@ type Config struct {
 	// This allows using existing OpenTracing instrumentation with OpenTelemetry
 	OTLPUseOpenTracingBridge bool `envconfig:"OTLP_USE_OPENTRACING_BRIDGE" default:"true"`
 }
+
+// Validate checks the configuration for common misconfigurations and returns
+// a list of warning messages. It does not return an error to avoid breaking
+// existing services — warnings are meant to be logged at startup.
+func (c Config) Validate() []string {
+	var warnings []string
+
+	if c.GRPCPort < 1 || c.GRPCPort > 65535 {
+		warnings = append(warnings, "GRPCPort is out of valid range (1-65535)")
+	}
+	if c.HTTPPort < 1 || c.HTTPPort > 65535 {
+		warnings = append(warnings, "HTTPPort is out of valid range (1-65535)")
+	}
+	if c.GRPCPort == c.HTTPPort && c.GRPCPort != 0 {
+		warnings = append(warnings, "GRPCPort and HTTPPort are the same, this will cause a port conflict")
+	}
+	if c.NewRelicOpentelemetrySample < 0 || c.NewRelicOpentelemetrySample > 1.0 {
+		warnings = append(warnings, "NewRelicOpentelemetrySample should be between 0.0 and 1.0")
+	}
+	if c.OTLPSamplingRatio < 0 || c.OTLPSamplingRatio > 1.0 {
+		warnings = append(warnings, "OTLPSamplingRatio should be between 0.0 and 1.0")
+	}
+	if (c.GRPCTLSCertFile == "") != (c.GRPCTLSKeyFile == "") {
+		warnings = append(warnings, "GRPCTLSCertFile and GRPCTLSKeyFile must both be set or both be empty")
+	}
+	if c.ShutdownDurationInSeconds > 0 && c.HealthcheckWaitDurationInSeconds > 0 &&
+		c.HealthcheckWaitDurationInSeconds >= c.ShutdownDurationInSeconds {
+		warnings = append(warnings, "HealthcheckWaitDurationInSeconds should be less than ShutdownDurationInSeconds")
+	}
+
+	return warnings
+}

core.go

@@ -439,6 +439,13 @@ func (c *cb) Run() error {
 		errChan <- c.runHTTP(ctx, c.httpServer)
 	}()
 	err = <-errChan
+	// One server failed — stop the other to ensure clean shutdown
+	if c.grpcServer != nil {
+		c.grpcServer.Stop()
+	}
+	if c.httpServer != nil {
+		c.httpServer.Close()
+	}
 	c.gracefulWait.Wait() // if graceful shutdown is in progress wait for it to finish
 	c.close()
 	return err
@@ -482,12 +489,9 @@ func (c *cb) Stop(dur time.Duration) error {
 	}
 	log.Info(context.Background(), "msg", "Server shut down started, bye bye")
 	if c.httpServer != nil {
-		go func(ctx context.Context, c *cb) {
-			err := c.httpServer.Shutdown(ctx)
-			if err != nil {
-				log.Error(context.Background(), "msg", "http server shutdown error", "err", err)
-			}
-		}(ctx, c) // shutdown http server gracefully
+		if err := c.httpServer.Shutdown(ctx); err != nil {
+			log.Error(context.Background(), "msg", "http server shutdown error", "err", err)
+		}
 	}
 	if c.grpcServer != nil {
 		timedCall(ctx, c.grpcServer.GracefulStop)
@@ -524,6 +528,11 @@ func timedCall(ctx context.Context, f func()) {
 // The services are added using the AddService method
 // The services are started and stopped in the order they are added
 func New(c config.Config) CB {
+	if warnings := c.Validate(); len(warnings) > 0 {
+		for _, w := range warnings {
+			log.Warn(context.Background(), "msg", "config validation warning", "warning", w)
+		}
+	}
 	impl := &cb{
 		config: c,
 		svc:    make([]CBService, 0),

initializers.go

@@ -115,6 +115,7 @@ func SetupReleaseName(rel string) {
 // Use SetupOpenTelemetry or SetupNROpenTelemetry instead, which support
 // OTLP-compatible backends including Jaeger's OTLP receiver.
 func setupJaeger(serviceName string) io.Closer {
+	log.Warn(context.Background(), "msg", "Jaeger client is deprecated and EOL. Please migrate to SetupOpenTelemetry or SetupNROpenTelemetry with OTLP-compatible backends.")
 	conf, err := jaegerconfig.FromEnv()
 	if err != nil {
 		log.Info(context.Background(), "msg", "could not initialize jaeger", "err", err)