Windows specific kubelet flags in kubeadm-flags.env

- Uses correct pause image for Windows
- Omits systemd specific flags
- Common build flags function to be used by Linux and Windows
- Uses user configured image repository for Windows pause image

cmd/kubeadm/app/constants/constants.go

@@ -265,9 +265,6 @@ const (
 	// DefaultEtcdVersion indicates the default etcd version that kubeadm uses
 	DefaultEtcdVersion = "3.4.3-0"
 
-	// PauseVersion indicates the default pause image version for kubeadm
-	PauseVersion = "3.2"
-
 	// Etcd defines variable used internally when referring to etcd component
 	Etcd = "etcd"
 	// KubeAPIServer defines variable used internally when referring to kube-apiserver component

cmd/kubeadm/app/constants/constants_unix.go

@@ -21,4 +21,7 @@ package constants
 const (
 	// DefaultDockerCRISocket defines the default Docker CRI socket
 	DefaultDockerCRISocket = "/var/run/dockershim.sock"
+
+	// PauseVersion indicates the default pause image version for kubeadm
+	PauseVersion = "3.2"
 )

cmd/kubeadm/app/constants/constants_windows.go

@@ -21,4 +21,7 @@ package constants
 const (
 	// DefaultDockerCRISocket defines the default Docker CRI socket
 	DefaultDockerCRISocket = "npipe:////./pipe/docker_engine"
+
+	// PauseVersion indicates the default pause image version for kubeadm
+	PauseVersion = "1.3.0"
 )

cmd/kubeadm/app/images/BUILD

@@ -8,14 +8,23 @@ load(
 
 go_library(
     name = "go_default_library",
-    srcs = ["images.go"],
+    srcs = [
+        "images.go",
+        "images_unix.go",
+        "images_windows.go",
+    ],
     importpath = "k8s.io/kubernetes/cmd/kubeadm/app/images",
     deps = [
         "//cmd/kubeadm/app/apis/kubeadm:go_default_library",
         "//cmd/kubeadm/app/constants:go_default_library",
         "//cmd/kubeadm/app/util:go_default_library",
         "//vendor/k8s.io/klog:go_default_library",
-    ],
+    ] + select({
+        "@io_bazel_rules_go//go/platform:windows": [
+            "//cmd/kubeadm/app/apis/kubeadm/v1beta2:go_default_library",
+        ],
+        "//conditions:default": [],
+    }),
 )
 
 go_test(

cmd/kubeadm/app/images/images.go

@@ -84,11 +84,6 @@ func GetEtcdImage(cfg *kubeadmapi.ClusterConfiguration) string {
 	return GetGenericImage(etcdImageRepository, constants.Etcd, etcdImageTag)
 }
 
-// GetPauseImage returns the image for the "pause" container
-func GetPauseImage(cfg *kubeadmapi.ClusterConfiguration) string {
-	return GetGenericImage(cfg.ImageRepository, "pause", constants.PauseVersion)
-}
-
 // GetControlPlaneImages returns a list of container images kubeadm expects to use on a control plane node
 func GetControlPlaneImages(cfg *kubeadmapi.ClusterConfiguration) []string {
 	imgs := []string{}

cmd/kubeadm/app/images/images_unix.go

@@ -0,0 +1,29 @@
+// +build !windows
+
+/*
+Copyright 2020 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 images
+
+import (
+	kubeadmapi "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
+	"k8s.io/kubernetes/cmd/kubeadm/app/constants"
+)
+
+// GetPauseImage returns the image for the "pause" container
+func GetPauseImage(cfg *kubeadmapi.ClusterConfiguration) string {
+	return GetGenericImage(cfg.ImageRepository, "pause", constants.PauseVersion)
+}

cmd/kubeadm/app/images/images_windows.go

@@ -0,0 +1,34 @@
+// +build windows
+
+/*
+Copyright 2020 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 images
+
+import (
+	kubeadmapi "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
+	kubeadmapiv1beta2 "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1beta2"
+	"k8s.io/kubernetes/cmd/kubeadm/app/constants"
+)
+
+// GetPauseImage returns the image for the "pause" container
+func GetPauseImage(cfg *kubeadmapi.ClusterConfiguration) string {
+	//If user has configured the cluster to use a different image repository, use that for the Windows pause image.
+	if cfg.ImageRepository != kubeadmapiv1beta2.DefaultImageRepository {
+		return GetGenericImage(cfg.ImageRepository, "pause", constants.PauseVersion)
+	}
+	return GetGenericImage("mcr.microsoft.com/oss/kubernetes", "pause", constants.PauseVersion)
+}

cmd/kubeadm/app/phases/kubelet/BUILD

@@ -6,6 +6,8 @@ go_library(
         "config.go",
         "dynamic.go",
         "flags.go",
+        "flags_unix.go",
+        "flags_windows.go",
         "kubelet.go",
     ],
     importpath = "k8s.io/kubernetes/cmd/kubeadm/app/phases/kubelet",

cmd/kubeadm/app/phases/kubelet/flags.go

@@ -18,12 +18,8 @@ package kubelet
 
 import (
 	"fmt"
-	"io/ioutil"
-	"os"
-	"path/filepath"
-	"strings"
-
 	"github.com/pkg/errors"
+	"io/ioutil"
 	"k8s.io/klog"
 	kubeadmapi "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
 	"k8s.io/kubernetes/cmd/kubeadm/app/constants"
@@ -32,6 +28,9 @@ import (
 	kubeadmutil "k8s.io/kubernetes/cmd/kubeadm/app/util"
 	"k8s.io/kubernetes/cmd/kubeadm/app/util/initsystem"
 	utilsexec "k8s.io/utils/exec"
+	"os"
+	"path/filepath"
+	"strings"
 )
 
 type kubeletFlagsOpts struct {
@@ -85,20 +84,14 @@ func WriteKubeletDynamicEnvFile(cfg *kubeadmapi.ClusterConfiguration, nodeReg *k
 	return writeKubeletFlagBytesToDisk([]byte(envFileContent), kubeletDir)
 }
 
-// buildKubeletArgMap takes a kubeletFlagsOpts object and builds based on that a string-string map with flags
-// that should be given to the local kubelet daemon.
-func buildKubeletArgMap(opts kubeletFlagsOpts) map[string]string {
+//buildKubeletArgMapCommon takes a kubeletFlagsOpts object and builds based on that a string-string map with flags
+//that are common to both Linux and Windows
+func buildKubeletArgMapCommon(opts kubeletFlagsOpts) map[string]string {
 	kubeletFlags := map[string]string{}
 
 	if opts.nodeRegOpts.CRISocket == constants.DefaultDockerCRISocket {
 		// These flags should only be set when running docker
 		kubeletFlags["network-plugin"] = "cni"
-		driver, err := kubeadmutil.GetCgroupDriverDocker(opts.execer)
-		if err != nil {
-			klog.Warningf("cannot automatically assign a '--cgroup-driver' value when starting the Kubelet: %v\n", err)
-		} else {
-			kubeletFlags["cgroup-driver"] = driver
-		}
 		if opts.pauseImage != "" {
 			kubeletFlags["pod-infra-container-image"] = opts.pauseImage
 		}
@@ -116,14 +109,6 @@ func buildKubeletArgMap(opts kubeletFlagsOpts) map[string]string {
 		kubeletFlags["register-with-taints"] = strings.Join(taintStrs, ",")
 	}
 
-	ok, err := opts.isServiceActiveFunc("systemd-resolved")
-	if err != nil {
-		klog.Warningf("cannot determine if systemd-resolved is active: %v\n", err)
-	}
-	if ok {
-		kubeletFlags["resolv-conf"] = "/run/systemd/resolve/resolv.conf"
-	}
-
 	// Pass the "--hostname-override" flag to the kubelet only if it's different from the hostname
 	nodeName, hostname, err := GetNodeNameAndHostname(opts.nodeRegOpts)
 	if err != nil {
@@ -134,8 +119,6 @@ func buildKubeletArgMap(opts kubeletFlagsOpts) map[string]string {
 		kubeletFlags["hostname-override"] = nodeName
 	}
 
-	// TODO: Conditionally set `--cgroup-driver` to either `systemd` or `cgroupfs` for CRI other than Docker
-
 	// TODO: The following code should be removed after dual-stack is GA.
 	// Note: The user still retains the ability to explicitly set feature-gates and that value will overwrite this base value.
 	if enabled, present := opts.featureGates[features.IPv6DualStack]; present {

cmd/kubeadm/app/phases/kubelet/flags_unix.go

@@ -0,0 +1,51 @@
+// +build !windows
+
+/*
+Copyright 2020 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 kubelet
+
+import (
+	"k8s.io/klog"
+	"k8s.io/kubernetes/cmd/kubeadm/app/constants"
+	kubeadmutil "k8s.io/kubernetes/cmd/kubeadm/app/util"
+)
+
+// buildKubeletArgMap takes a kubeletFlagsOpts object and builds based on that a string-string map with flags
+// that should be given to the local Linux kubelet daemon.
+func buildKubeletArgMap(opts kubeletFlagsOpts) map[string]string {
+	kubeletFlags := buildKubeletArgMapCommon(opts)
+
+	// TODO: Conditionally set `--cgroup-driver` to either `systemd` or `cgroupfs` for CRI other than Docker
+	if opts.nodeRegOpts.CRISocket == constants.DefaultDockerCRISocket {
+		driver, err := kubeadmutil.GetCgroupDriverDocker(opts.execer)
+		if err != nil {
+			klog.Warningf("cannot automatically assign a '--cgroup-driver' value when starting the Kubelet: %v\n", err)
+		} else {
+			kubeletFlags["cgroup-driver"] = driver
+		}
+	}
+
+	ok, err := opts.isServiceActiveFunc("systemd-resolved")
+	if err != nil {
+		klog.Warningf("cannot determine if systemd-resolved is active: %v\n", err)
+	}
+	if ok {
+		kubeletFlags["resolv-conf"] = "/run/systemd/resolve/resolv.conf"
+	}
+
+	return kubeletFlags
+}

cmd/kubeadm/app/phases/kubelet/flags_windows.go

@@ -0,0 +1,25 @@
+// +build windows
+
+/*
+Copyright 2020 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 kubelet
+
+// buildKubeletArgMap takes a kubeletFlagsOpts object and builds based on that a string-string map with flags
+// that should be given to the local Windows kubelet daemon.
+func buildKubeletArgMap(opts kubeletFlagsOpts) map[string]string {
+	return buildKubeletArgMapCommon(opts)
+}