CFE-986: Reload router when defaultDestinationCA is updated

pkg/router/template/router.go

@@ -281,6 +281,9 @@ func newTemplateRouter(cfg templateRouterCfg) (*templateRouter, error) {
 	if err := router.watchMutualTLSCert(); err != nil {
 		return nil, err
 	}
+	if err := router.watchCABundleCert(); err != nil {
+		return nil, err
+	}
 	if router.dynamicConfigManager != nil {
 		log.V(0).Info("initializing dynamic config manager ... ")
 		router.dynamicConfigManager.Initialize(router, router.defaultCertificatePath)
@@ -1489,3 +1492,24 @@ func privateKeysFromPEM(pemCerts []byte) ([]byte, error) {
 	}
 	return buf.Bytes(), nil
 }
+
+// watchCABundleCert watches the directory containing the CA bundle certificate
+// and reloads the router if the directory contents change.
+func (r *templateRouter) watchCABundleCert() error {
+	caBundleDir := filepath.Dir(r.defaultDestinationCAPath)
+
+	reloadFn := func() {
+		if err := r.reloadRouter(false); err != nil {
+			log.V(0).Error(err, "failed to reload router after detecting changes in CA bundle certificate directory")
+			return
+		}
+		log.V(0).Info("router was reloaded after detecting changes in CA bundle certificate directory")
+	}
+
+	if err := r.watchVolumeMountDir(caBundleDir, reloadFn); err != nil {
+		log.V(0).Error(err, "failed to establish watch on CA bundle certificate directory")
+		return err
+	}
+
+	return nil
+}