Use GetVersion() API instead of ver command

pkg/kubelet/winstats/BUILD

@@ -25,6 +25,7 @@ go_library(
         "@io_bazel_rules_go//go/platform:windows_amd64": [
             "perfcounter_nodestats.go",
             "perfcounters.go",
+            "version.go",
         ],
         "//conditions:default": [],
     }),
@@ -36,6 +37,7 @@ go_library(
         "@io_bazel_rules_go//go/platform:windows_amd64": [
             "//vendor/github.com/JeffAshton/win_pdh:go_default_library",
             "//vendor/github.com/golang/glog:go_default_library",
+            "//vendor/golang.org/x/sys/windows:go_default_library",
             "//vendor/k8s.io/apimachinery/pkg/util/wait:go_default_library",
         ],
         "//conditions:default": [],

pkg/kubelet/winstats/perfcounter_nodestats.go

@@ -21,9 +21,7 @@ package winstats
 import (
 	"errors"
 	"os"
-	"os/exec"
 	"runtime"
-	"strings"
 	"sync"
 	"syscall"
 	"time"
@@ -57,13 +55,16 @@ func (p *perfCounterNodeStatsClient) startMonitoring() error {
 		return err
 	}
 
-	version, err := exec.Command("cmd", "/C", "ver").Output()
+	kernelVersion, err := getKernelVersion()
+	if err != nil {
+		return err
+	}
+
+	osImageVersion, err := getOSImageVersion()
 	if err != nil {
 		return err
 	}
 
-	osImageVersion := strings.TrimSpace(string(version))
-	kernelVersion := extractVersionNumber(osImageVersion)
 	p.nodeInfo = nodeInfo{
 		kernelVersion:               kernelVersion,
 		osImageVersion:              osImageVersion,

pkg/kubelet/winstats/version.go

@@ -0,0 +1,96 @@
+// +build windows
+
+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package winstats
+
+import (
+	"fmt"
+	"unsafe"
+
+	"golang.org/x/sys/windows"
+)
+
+// getCurrentVersionVal gets value of speficied key from registry.
+func getCurrentVersionVal(key string) (string, error) {
+	var h windows.Handle
+	if err := windows.RegOpenKeyEx(windows.HKEY_LOCAL_MACHINE,
+		windows.StringToUTF16Ptr(`SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion\\`),
+		0,
+		windows.KEY_READ,
+		&h); err != nil {
+		return "", err
+	}
+	defer windows.RegCloseKey(h)
+
+	var buf [128]uint16
+	var typ uint32
+	n := uint32(len(buf) * int(unsafe.Sizeof(buf[0]))) // api expects array of bytes, not uint16
+	if err := windows.RegQueryValueEx(h,
+		windows.StringToUTF16Ptr(key),
+		nil,
+		&typ,
+		(*byte)(unsafe.Pointer(&buf[0])),
+		&n); err != nil {
+		return "", err
+	}
+
+	return windows.UTF16ToString(buf[:]), nil
+}
+
+// getVersionRevision gets revision from UBR registry.
+func getVersionRevision() (uint16, error) {
+	revisionString, err := getCurrentVersionVal("UBR")
+	if err != nil {
+		return 0, err
+	}
+
+	revision, err := windows.UTF16FromString(revisionString)
+	if err != nil {
+		return 0, err
+	}
+
+	return revision[0], nil
+}
+
+// getKernelVersion gets the version of windows kernel.
+func getKernelVersion() (string, error) {
+	ver, err := windows.GetVersion()
+	if err != nil {
+		return "", err
+	}
+
+	revision, err := getVersionRevision()
+	if err != nil {
+		return "", err
+	}
+
+	major := ver & 0xFF
+	minor := (ver >> 8) & 0xFF
+	build := (ver >> 16) & 0xFFFF
+	return fmt.Sprintf("%d.%d.%05d.%d\n", major, minor, build, revision), nil
+}
+
+// getOSImageVersion gets the osImage name and version.
+func getOSImageVersion() (string, error) {
+	productName, err := getCurrentVersionVal("ProductName")
+	if err != nil {
+		return "", nil
+	}
+
+	return productName, nil
+}

pkg/kubelet/winstats/winstats.go

@@ -18,7 +18,6 @@ limitations under the License.
 package winstats
 
 import (
-	"regexp"
 	"time"
 
 	cadvisorapi "github.com/google/cadvisor/info/v1"
@@ -135,11 +134,3 @@ func (c *statsClient) createRootContainerInfo() (*cadvisorapiv2.ContainerInfo, e
 
 	return &rootInfo, nil
 }
-
-// extractVersionNumber gets the version number from the full version string on Windows
-// e.g. extracts "10.0.14393" from "Microsoft Windows [Version 10.0.14393]"
-func extractVersionNumber(fullVersion string) string {
-	re := regexp.MustCompile("[^0-9.]")
-	version := re.ReplaceAllString(fullVersion, "")
-	return version
-}

pkg/kubelet/winstats/winstats_test.go

@@ -116,13 +116,6 @@ func TestWinVersionInfo(t *testing.T) {
 		KernelVersion: "v42"})
 }
 
-func TestExtractVersionNumber(t *testing.T) {
-	fullVersion := "Microsoft Windows [Version 10.0.14393]"
-	versionNumber := extractVersionNumber(fullVersion)
-	expected := "10.0.14393"
-	assert.Equal(t, expected, versionNumber)
-}
-
 func getClient(t *testing.T) Client {
 	f := fakeWinNodeStatsClient{}
 	c, err := newClient(f)