added better matching for PV access modes

pkg/api/helpers.go

@@ -20,6 +20,7 @@ import (
 	"crypto/md5"
 	"fmt"
 	"reflect"
+	"strings"
 
 	"k8s.io/kubernetes/pkg/api/resource"
 	"k8s.io/kubernetes/pkg/conversion"
@@ -179,3 +180,58 @@ func LoadBalancerStatusDeepCopy(lb *LoadBalancerStatus) *LoadBalancerStatus {
 	}
 	return c
 }
+
+// GetAccessModesAsString returns a string representation of an array of access modes.
+// modes, when present, are always in the same order: RWO,ROX,RWX.
+func GetAccessModesAsString(modes []PersistentVolumeAccessMode) string {
+	modes = removeDuplicateAccessModes(modes)
+	modesStr := []string{}
+	if containsAccessMode(modes, ReadWriteOnce) {
+		modesStr = append(modesStr, "RWO")
+	}
+	if containsAccessMode(modes, ReadOnlyMany) {
+		modesStr = append(modesStr, "ROX")
+	}
+	if containsAccessMode(modes, ReadWriteMany) {
+		modesStr = append(modesStr, "RWX")
+	}
+	return strings.Join(modesStr, ",")
+}
+
+// GetAccessModesAsString returns an array of AccessModes from a string created by GetAccessModesAsString
+func GetAccessModesFromString(modes string) []PersistentVolumeAccessMode {
+	strmodes := strings.Split(modes, ",")
+	accessModes := []PersistentVolumeAccessMode{}
+	for _, s := range strmodes {
+		s = strings.Trim(s, " ")
+		switch {
+		case s == "RWO":
+			accessModes = append(accessModes, ReadWriteOnce)
+		case s == "ROX":
+			accessModes = append(accessModes, ReadOnlyMany)
+		case s == "RWX":
+			accessModes = append(accessModes, ReadWriteMany)
+		}
+	}
+	return accessModes
+}
+
+// removeDuplicateAccessModes returns an array of access modes without any duplicates
+func removeDuplicateAccessModes(modes []PersistentVolumeAccessMode) []PersistentVolumeAccessMode {
+	accessModes := []PersistentVolumeAccessMode{}
+	for _, m := range modes {
+		if !containsAccessMode(accessModes, m) {
+			accessModes = append(accessModes, m)
+		}
+	}
+	return accessModes
+}
+
+func containsAccessMode(modes []PersistentVolumeAccessMode, mode PersistentVolumeAccessMode) bool {
+	for _, m := range modes {
+		if m == mode {
+			return true
+		}
+	}
+	return false
+}