Add label support to named volumes in docker compose v3 to Kubernetes (#1083)

* Support read specific label (kompose.volume.size) from named volume and apply to kubernetes supported volume size

* Fix the PVC size in log message when deploy Kubernetes

* Skip creation of PersistentVolumeClaim if it is already created in the same kubernetes deploy

* Add selector to PersistentVolumeClaim only when specific label (kompose.volume.selector) is used in named volume

* Add test case to named-volume for the new labels

pkg/loader/compose/v3.go

@@ -422,11 +422,51 @@ func dockerComposeToKomposeMapping(composeObject *types.Config) (kobject.Kompose
 		komposeObject.ServiceConfigs[normalizeServiceNames(name)] = serviceConfig
 	}
 
-	handleVolume(&komposeObject)
+	handleV3Volume(&komposeObject, &composeObject.Volumes)
 
 	return komposeObject, nil
 }
 
+func handleV3Volume(komposeObject *kobject.KomposeObject, volumes *map[string]types.VolumeConfig) {
+	for name := range komposeObject.ServiceConfigs {
+		// retrieve volumes of service
+		vols, err := retrieveVolume(name, *komposeObject)
+		if err != nil {
+			errors.Wrap(err, "could not retrieve vvolume")
+		}
+		for volName, vol := range vols {
+			size, selector := getV3VolumeLabels(vol.VolumeName, volumes)
+			if len(size) > 0 || len(selector) > 0 {
+				// We can't assign value to struct field in map while iterating over it, so temporary variable `temp` is used here
+				var temp = vols[volName]
+				temp.PVCSize = size
+				temp.SelectorValue = selector
+				vols[volName] = temp
+			}
+		}
+		// We can't assign value to struct field in map while iterating over it, so temporary variable `temp` is used here
+		var temp = komposeObject.ServiceConfigs[name]
+		temp.Volumes = vols
+		komposeObject.ServiceConfigs[name] = temp
+	}
+}
+
+func getV3VolumeLabels(name string, volumes *map[string]types.VolumeConfig) (string, string) {
+	size, selector := "", ""
+
+	if volume, ok := (*volumes)[name]; ok {
+		for key, value := range volume.Labels {
+			if key == "kompose.volume.size" {
+				size = value
+			} else if key == "kompose.volume.selector" {
+				selector = value
+			}
+		}
+	}
+
+	return size, selector
+}
+
 func mergeComposeObject(oldCompose *types.Config, newCompose *types.Config) (*types.Config, error) {
 	if oldCompose == nil || newCompose == nil {
 		return nil, fmt.Errorf("Merge multiple compose error, compose config is nil")