[exporter/prometheus] close server on shutdown

exporter/prometheusexporter/prometheus.go

@@ -20,7 +20,7 @@ type prometheusExporter struct {
 	config       Config
 	name         string
 	endpoint     string
-	shutdownFunc func() error
+	shutdownFunc func(ctx context.Context) error
 	handler      http.Handler
 	collector    *collector
 	registry     *prometheus.Registry
@@ -44,7 +44,7 @@ func newPrometheusExporter(config *Config, set exporter.Settings) (*prometheusEx
 		endpoint:     addr,
 		collector:    collector,
 		registry:     registry,
-		shutdownFunc: func() error { return nil },
+		shutdownFunc: func(_ context.Context) error { return nil },
 		handler: promhttp.HandlerFor(
 			registry,
 			promhttp.HandlerOpts{
@@ -63,11 +63,14 @@ func (pe *prometheusExporter) Start(ctx context.Context, host component.Host) er
 		return err
 	}
 
-	pe.shutdownFunc = ln.Close
-
 	mux := http.NewServeMux()
 	mux.Handle("/metrics", pe.handler)
 	srv, err := pe.config.ToServer(ctx, host, pe.settings, mux)
+	pe.shutdownFunc = func(ctx context.Context) error {
+		err := ln.Close()
+		err2 := srv.Shutdown(ctx)
+		return errors.Join(err, err2)
+	}
 	if err != nil {
 		return err
 	}
@@ -88,6 +91,6 @@ func (pe *prometheusExporter) ConsumeMetrics(_ context.Context, md pmetric.Metri
 	return nil
 }
 
-func (pe *prometheusExporter) Shutdown(context.Context) error {
-	return pe.shutdownFunc()
+func (pe *prometheusExporter) Shutdown(ctx context.Context) error {
+	return pe.shutdownFunc(ctx)
 }