fix: stop redirect siblings on shutdown

Make the non-graceful HTTPS redirect path shut down all sibling servers after any server returns, so cleanup stays consistent with the graceful path and partial shutdowns do not leave the redirect listener running.

serve.go

@@ -518,13 +518,16 @@ func (engine *Engine) Run(opts ...RunOption) error {
 			}
 
 			err := <-serverStopped
-			if err != nil && !errors.Is(err, http.ErrServerClosed) {
 			if shutdownErr := shutdownServers(servers, defaultShutdownTimeout); shutdownErr != nil {
+				if err != nil && !errors.Is(err, http.ErrServerClosed) {
 					return errors.Join(err, shutdownErr)
 				}
+				return shutdownErr
+			}
+			if err != nil && !errors.Is(err, http.ErrServerClosed) {
 				return err
 			}
-			return err
+			return nil
 		}
 
 		protocolLabel := "HTTP"

serve_test.go

@@ -2,9 +2,15 @@ package touka
 
 import (
 	"context"
+	"crypto/rand"
+	"crypto/rsa"
 	"crypto/tls"
+	"crypto/x509"
+	"crypto/x509/pkix"
+	"encoding/pem"
 	"errors"
 	"io"
+	"math/big"
 	"net"
 	"net/http"
 	"net/http/httptest"
@@ -13,6 +19,41 @@ import (
 	"time"
 )
 
+func generateSelfSignedCert(t *testing.T) tls.Certificate {
+	t.Helper()
+
+	privateKey, err := rsa.GenerateKey(rand.Reader, 2048)
+	if err != nil {
+		t.Fatalf("generate private key: %v", err)
+	}
+
+	tmpl := &x509.Certificate{
+		SerialNumber: big.NewInt(1),
+		Subject:      pkix.Name{CommonName: "127.0.0.1"},
+		NotBefore:    time.Now().Add(-time.Hour),
+		NotAfter:     time.Now().Add(time.Hour),
+		KeyUsage:     x509.KeyUsageKeyEncipherment | x509.KeyUsageDigitalSignature,
+		ExtKeyUsage: []x509.ExtKeyUsage{
+			x509.ExtKeyUsageServerAuth,
+		},
+		IPAddresses: []net.IP{net.ParseIP("127.0.0.1")},
+	}
+
+	der, err := x509.CreateCertificate(rand.Reader, tmpl, tmpl, &privateKey.PublicKey, privateKey)
+	if err != nil {
+		t.Fatalf("create self-signed cert: %v", err)
+	}
+
+	certPEM := pem.EncodeToMemory(&pem.Block{Type: "CERTIFICATE", Bytes: der})
+	keyPEM := pem.EncodeToMemory(&pem.Block{Type: "RSA PRIVATE KEY", Bytes: x509.MarshalPKCS1PrivateKey(privateKey)})
+
+	cert, err := tls.X509KeyPair(certPEM, keyPEM)
+	if err != nil {
+		t.Fatalf("parse self-signed cert: %v", err)
+	}
+	return cert
+}
+
 func TestServeServerHTTPModeIgnoresTLSConfig(t *testing.T) {
 	listener, err := net.Listen("tcp", "127.0.0.1:0")
 	if err != nil {