Implement metrics for Windows Nodes

This implements stats for windows nodes in a new package, winstats.
WinStats exports methods to get cadvisor like datastructures, however
with windows specific metrics. WinStats only gets node level metrics and
information, container stats will go via the CRI. This enables the
use of the summary api to get metrics for windows nodes.

pkg/kubelet/winstats/winstats_test.go

@@ -0,0 +1,132 @@
+/*
+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 (
+	"testing"
+	"time"
+
+	cadvisorapi "github.com/google/cadvisor/info/v1"
+	cadvisorapiv2 "github.com/google/cadvisor/info/v2"
+	"github.com/stretchr/testify/assert"
+)
+
+var timeStamp = time.Now()
+
+type fakeWinNodeStatsClient struct{}
+
+func (f fakeWinNodeStatsClient) startMonitoring() error {
+	return nil
+}
+
+func (f fakeWinNodeStatsClient) getNodeMetrics() (nodeMetrics, error) {
+	return nodeMetrics{
+		cpuUsageCoreNanoSeconds:   123,
+		memoryPrivWorkingSetBytes: 1234,
+		memoryCommittedBytes:      12345,
+		timeStamp:                 timeStamp,
+	}, nil
+}
+
+func (f fakeWinNodeStatsClient) getNodeInfo() nodeInfo {
+	return nodeInfo{
+		kernelVersion:               "v42",
+		memoryPhysicalCapacityBytes: 1.6e+10,
+	}
+}
+func (f fakeWinNodeStatsClient) getMachineInfo() (*cadvisorapi.MachineInfo, error) {
+	return &cadvisorapi.MachineInfo{
+		NumCores:       4,
+		MemoryCapacity: 1.6e+10,
+		MachineID:      "somehostname",
+	}, nil
+}
+
+func (f fakeWinNodeStatsClient) getVersionInfo() (*cadvisorapi.VersionInfo, error) {
+	return &cadvisorapi.VersionInfo{
+		KernelVersion: "v42",
+	}, nil
+}
+
+func TestWinContainerInfos(t *testing.T) {
+	c := getClient(t)
+
+	actualRootInfos, err := c.WinContainerInfos()
+	assert.NoError(t, err)
+
+	var stats []*cadvisorapiv2.ContainerStats
+	stats = append(stats, &cadvisorapiv2.ContainerStats{
+		Timestamp: timeStamp,
+		Cpu: &cadvisorapi.CpuStats{
+			Usage: cadvisorapi.CpuUsage{
+				Total: 123,
+			},
+		},
+		Memory: &cadvisorapi.MemoryStats{
+			WorkingSet: 1234,
+			Usage:      12345,
+		},
+	})
+	infos := make(map[string]cadvisorapiv2.ContainerInfo)
+	infos["/"] = cadvisorapiv2.ContainerInfo{
+		Spec: cadvisorapiv2.ContainerSpec{
+			HasCpu:    true,
+			HasMemory: true,
+			Memory: cadvisorapiv2.MemorySpec{
+				Limit: 1.6e+10,
+			},
+		},
+		Stats: stats,
+	}
+
+	assert.Equal(t, actualRootInfos, infos)
+}
+
+func TestWinMachineInfo(t *testing.T) {
+	c := getClient(t)
+
+	machineInfo, err := c.WinMachineInfo()
+	assert.NoError(t, err)
+	assert.Equal(t, machineInfo, &cadvisorapi.MachineInfo{
+		NumCores:       4,
+		MemoryCapacity: 1.6e+10,
+		MachineID:      "somehostname"})
+}
+
+func TestWinVersionInfo(t *testing.T) {
+	c := getClient(t)
+
+	versionInfo, err := c.WinVersionInfo()
+	assert.NoError(t, err)
+	assert.Equal(t, versionInfo, &cadvisorapi.VersionInfo{
+		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)
+	assert.NoError(t, err)
+	assert.NotNil(t, c)
+	return c
+}