Merge pull request #63580 from dixudx/fix_cni_flag_binding

Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

bind alpha feature network plugin flags correctly

**What this PR does / why we need it**:
When working #63542, I found the flags, like `--cni-conf-dir` and `cni-bin-dir`, were not correctly bound.

**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #

**Special notes for your reviewer**:
/cc kubernetes/sig-node-pr-reviews

**Release note**:

```release-note
None
```

cmd/kubelet/app/BUILD

@@ -92,9 +92,6 @@ go_library(
         "//pkg/kubelet/config:go_default_library",
         "//pkg/kubelet/container:go_default_library",
         "//pkg/kubelet/dockershim:go_default_library",
-        "//pkg/kubelet/dockershim/network:go_default_library",
-        "//pkg/kubelet/dockershim/network/cni:go_default_library",
-        "//pkg/kubelet/dockershim/network/kubenet:go_default_library",
         "//pkg/kubelet/dockershim/remote:go_default_library",
         "//pkg/kubelet/eviction:go_default_library",
         "//pkg/kubelet/eviction/api:go_default_library",

cmd/kubelet/app/options/container_runtime.go

@@ -53,5 +53,9 @@ func NewContainerRuntimeOptions() *config.ContainerRuntimeOptions {
 		PodSandboxImage:            defaultPodSandboxImage,
 		ImagePullProgressDeadline:  metav1.Duration{Duration: 1 * time.Minute},
 		ExperimentalDockershim:     false,
+
+		//Alpha feature
+		CNIBinDir:  "/opt/cni/bin",
+		CNIConfDir: "/etc/cni/net.d",
 	}
 }

cmd/kubelet/app/plugins.go

@@ -23,10 +23,6 @@ import (
 	_ "k8s.io/kubernetes/pkg/credentialprovider/azure"
 	_ "k8s.io/kubernetes/pkg/credentialprovider/gcp"
 	_ "k8s.io/kubernetes/pkg/credentialprovider/rancher"
-	// Network plugins
-	"k8s.io/kubernetes/pkg/kubelet/dockershim/network"
-	"k8s.io/kubernetes/pkg/kubelet/dockershim/network/cni"
-	"k8s.io/kubernetes/pkg/kubelet/dockershim/network/kubenet"
 	// Volume plugins
 	"k8s.io/kubernetes/pkg/volume"
 	"k8s.io/kubernetes/pkg/volume/aws_ebs"
@@ -112,14 +108,3 @@ func ProbeVolumePlugins() []volume.VolumePlugin {
 func GetDynamicPluginProber(pluginDir string) volume.DynamicPluginProber {
 	return flexvolume.GetDynamicPluginProber(pluginDir)
 }
-
-// ProbeNetworkPlugins collects all compiled-in plugins
-func ProbeNetworkPlugins(cniConfDir string, cniBinDirs []string) []network.NetworkPlugin {
-	allPlugins := []network.NetworkPlugin{}
-
-	// for each existing plugin, add to the list
-	allPlugins = append(allPlugins, cni.ProbeNetworkPlugins(cniConfDir, cniBinDirs)...)
-	allPlugins = append(allPlugins, kubenet.NewPlugin(cniBinDirs))
-
-	return allPlugins
-}

pkg/kubelet/config/flags.go

@@ -96,12 +96,12 @@ func (s *ContainerRuntimeOptions) AddFlags(fs *pflag.FlagSet) {
 	fs.BoolVar(&s.DockerDisableSharedPID, "docker-disable-shared-pid", s.DockerDisableSharedPID, fmt.Sprintf("Setting this to false causes Kubernetes to create pods using a shared process namespace for containers in a pod when running with Docker 1.13.1 or higher. A future Kubernetes release will make this configurable instead in the API. %s", dockerOnlyWarning))
 	fs.MarkDeprecated("docker-disable-shared-pid", "will be removed in a future release. This option will be replaced by PID namespace sharing that is configurable per-pod using the API. See https://features.k8s.io/495")
 	fs.StringVar(&s.PodSandboxImage, "pod-infra-container-image", s.PodSandboxImage, fmt.Sprintf("The image whose network/ipc namespaces containers in each pod will use. %s", dockerOnlyWarning))
-	fs.StringVar(&s.DockerEndpoint, "docker-endpoint", s.DockerEndpoint, fmt.Sprintf("Use this for the docker endpoint to communicate with %s", dockerOnlyWarning))
+	fs.StringVar(&s.DockerEndpoint, "docker-endpoint", s.DockerEndpoint, fmt.Sprintf("Use this for the docker endpoint to communicate with. %s", dockerOnlyWarning))
 	fs.DurationVar(&s.ImagePullProgressDeadline.Duration, "image-pull-progress-deadline", s.ImagePullProgressDeadline.Duration, fmt.Sprintf("If no pulling progress is made before this deadline, the image pulling will be cancelled. %s", dockerOnlyWarning))
 
 	// Network plugin settings for Docker.
 	fs.StringVar(&s.NetworkPluginName, "network-plugin", s.NetworkPluginName, fmt.Sprintf("<Warning: Alpha feature> The name of the network plugin to be invoked for various events in kubelet/pod lifecycle. %s", dockerOnlyWarning))
-	fs.StringVar(&s.CNIConfDir, "cni-conf-dir", s.CNIConfDir, fmt.Sprintf("<Warning: Alpha feature> The full path of the directory in which to search for CNI config files. Default: /etc/cni/net.d. %s", dockerOnlyWarning))
-	fs.StringVar(&s.CNIBinDir, "cni-bin-dir", s.CNIBinDir, fmt.Sprintf("<Warning: Alpha feature> A comma-separated list of full paths of directories in which to search for CNI plugin binaries. Default: /opt/cni/bin. %s", dockerOnlyWarning))
+	fs.StringVar(&s.CNIConfDir, "cni-conf-dir", s.CNIConfDir, fmt.Sprintf("<Warning: Alpha feature> The full path of the directory in which to search for CNI config files. %s", dockerOnlyWarning))
+	fs.StringVar(&s.CNIBinDir, "cni-bin-dir", s.CNIBinDir, fmt.Sprintf("<Warning: Alpha feature> A comma-separated list of full paths of directories in which to search for CNI plugin binaries. %s", dockerOnlyWarning))
 	fs.Int32Var(&s.NetworkPluginMTU, "network-plugin-mtu", s.NetworkPluginMTU, fmt.Sprintf("<Warning: Alpha feature> The MTU to be passed to the network plugin, to override the default. Set to 0 to use the default 1460 MTU. %s", dockerOnlyWarning))
 }

pkg/kubelet/dockershim/network/cni/cni.go

@@ -33,9 +33,7 @@ import (
 )
 
 const (
-	CNIPluginName  = "cni"
-	DefaultConfDir = "/etc/cni/net.d"
-	DefaultBinDir  = "/opt/cni/bin"
+	CNIPluginName = "cni"
 )
 
 type cniNetworkPlugin struct {
@@ -81,13 +79,6 @@ func ProbeNetworkPlugins(confDir string, binDirs []string) []network.NetworkPlug
 			binDirs = append(binDirs, dir)
 		}
 	}
-	if len(binDirs) == 0 {
-		binDirs = []string{DefaultBinDir}
-	}
-
-	if confDir == "" {
-		confDir = DefaultConfDir
-	}
 
 	plugin := &cniNetworkPlugin{
 		defaultNetwork: nil,