Address PR review feedback

Signed-off-by: Dimitar Kostadinov <dimitar.kostadinov@sap.com>

registry/handlers/app.go

@@ -412,12 +412,11 @@ func (app *App) RegisterHealthChecks(healthRegistries ...*health.Registry) {
 }
 
 // OnExit close the underlying registry
-func (app *App) OnExit() {
-	if app.isCache {
-		if regProxy, ok := app.registry.(proxy.Closable); ok {
-			regProxy.Close()
-		}
+func (app *App) OnExit() error {
+	if r, ok := app.registry.(proxy.Closer); ok {
+		return r.Close()
 	}
+	return nil
 }
 
 // register a handler with the application, by route name. The handler will be

registry/proxy/proxyregistry.go

@@ -211,13 +211,13 @@ func (pr *proxyingRegistry) BlobStatter() distribution.BlobStatter {
 	return pr.embedded.BlobStatter()
 }
 
-type Closable interface {
+type Closer interface {
 	// Close release all resources used by this object
-	Close()
+	Close() error
 }
 
-func (pr *proxyingRegistry) Close() {
-	pr.scheduler.Stop()
+func (pr *proxyingRegistry) Close() error {
+	return pr.scheduler.Stop()
 }
 
 // authChallenger encapsulates a request to the upstream to establish credential challenges

registry/proxy/scheduler/scheduler.go

@@ -206,12 +206,13 @@ func (ttles *TTLExpirationScheduler) startTimer(entry *schedulerEntry, ttl time.
 }
 
 // Stop stops the scheduler.
-func (ttles *TTLExpirationScheduler) Stop() {
+func (ttles *TTLExpirationScheduler) Stop() error {
 	ttles.Lock()
 	defer ttles.Unlock()
 
-	if err := ttles.writeState(); err != nil {
-		dcontext.GetLogger(ttles.ctx).Errorf("Error writing scheduler state: %s", err)
+	err := ttles.writeState()
+	if err != nil {
+		err = fmt.Errorf("error writing scheduler state: %w", err)
 	}
 
 	for _, entry := range ttles.entries {
@@ -221,6 +222,7 @@ func (ttles *TTLExpirationScheduler) Stop() {
 	close(ttles.doneChan)
 	ttles.saveTimer.Stop()
 	ttles.stopped = true
+	return err
 }
 
 func (ttles *TTLExpirationScheduler) writeState() error {

registry/proxy/scheduler/scheduler_test.go

@@ -136,7 +136,12 @@ func TestRestoreOld(t *testing.T) {
 	if err != nil {
 		t.Fatalf("Error starting ttlExpirationScheduler: %s", err)
 	}
-	defer s.Stop()
+	defer func(s *TTLExpirationScheduler) {
+		err := s.Stop()
+		if err != nil {
+			t.Fatalf("Error stopping ttlExpirationScheduler: %s", err)
+		}
+	}(s)
 
 	wg.Wait()
 	mu.Lock()
@@ -177,7 +182,10 @@ func TestStopRestore(t *testing.T) {
 
 	// Start and stop before all operations complete
 	// state will be written to fs
-	s.Stop()
+	err = s.Stop()
+	if err != nil {
+		t.Fatalf(err.Error())
+	}
 	time.Sleep(10 * time.Millisecond)
 
 	// v2 will restore state from fs

registry/registry.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"crypto/tls"
 	"crypto/x509"
+	"errors"
 	"fmt"
 	"net/http"
 	"os"
@@ -221,7 +222,7 @@ func setDirectoryURL(directoryurl string) *acme.Client {
 }
 
 // ListenAndServe runs the registry's HTTP server.
-func (registry *Registry) ListenAndServe() error {
+func (registry *Registry) ListenAndServe() (err error) {
 	config := registry.config
 
 	ln, err := listener.NewListener(config.HTTP.Net, config.HTTP.Addr)
@@ -316,7 +317,11 @@ func (registry *Registry) ListenAndServe() error {
 	go func() {
 		serveErr <- registry.server.Serve(ln)
 	}()
-	defer registry.app.OnExit()
+	defer func(app *handlers.App) {
+		if exitErr := app.OnExit(); exitErr != nil {
+			err = errors.Join(err, exitErr)
+		}
+	}(registry.app)
 
 	select {
 	case err := <-serveErr: