Use TTL-based caching configmap manager in kubelet

pkg/api/v1/pod/util.go

@@ -197,6 +197,60 @@ func visitContainerSecretNames(container *v1.Container, visitor Visitor) bool {
 	return true
 }
 
+// VisitPodConfigmapNames invokes the visitor function with the name of every configmap
+// referenced by the pod spec. If visitor returns false, visiting is short-circuited.
+// Transitive references (e.g. pod -> pvc -> pv -> secret) are not visited.
+// Returns true if visiting completed, false if visiting was short-circuited.
+func VisitPodConfigmapNames(pod *v1.Pod, visitor Visitor) bool {
+	for i := range pod.Spec.InitContainers {
+		if !visitContainerConfigmapNames(&pod.Spec.InitContainers[i], visitor) {
+			return false
+		}
+	}
+	for i := range pod.Spec.Containers {
+		if !visitContainerConfigmapNames(&pod.Spec.Containers[i], visitor) {
+			return false
+		}
+	}
+	var source *v1.VolumeSource
+	for i := range pod.Spec.Volumes {
+		source = &pod.Spec.Volumes[i].VolumeSource
+		switch {
+		case source.Projected != nil:
+			for j := range source.Projected.Sources {
+				if source.Projected.Sources[j].ConfigMap != nil {
+					if !visitor(source.Projected.Sources[j].ConfigMap.Name) {
+						return false
+					}
+				}
+			}
+		case source.ConfigMap != nil:
+			if !visitor(source.ConfigMap.Name) {
+				return false
+			}
+		}
+	}
+	return true
+}
+
+func visitContainerConfigmapNames(container *v1.Container, visitor Visitor) bool {
+	for _, env := range container.EnvFrom {
+		if env.ConfigMapRef != nil {
+			if !visitor(env.ConfigMapRef.Name) {
+				return false
+			}
+		}
+	}
+	for _, envVar := range container.Env {
+		if envVar.ValueFrom != nil && envVar.ValueFrom.ConfigMapKeyRef != nil {
+			if !visitor(envVar.ValueFrom.ConfigMapKeyRef.Name) {
+				return false
+			}
+		}
+	}
+	return true
+}
+
 // GetContainerStatus extracts the status of container "name" from "statuses".
 // It also returns if "name" exists.
 func GetContainerStatus(statuses []v1.ContainerStatus, name string) (v1.ContainerStatus, bool) {