kubeadm - addon configuration in the kubeadm config API.

cmd/kubeadm/app/apis/kubeadm/fuzzer/fuzzer.go

@@ -18,7 +18,6 @@ package fuzzer
 
 import (
 	fuzz "github.com/google/gofuzz"
-
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	runtimeserializer "k8s.io/apimachinery/pkg/runtime/serializer"
 	"k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
@@ -34,6 +33,7 @@ func Funcs(codecs runtimeserializer.CodecFactory) []interface{} {
 		fuzzAuditPolicyConfiguration,
 		fuzzComponentConfigs,
 		fuzzNodeRegistration,
+		fuzzDNS,
 		fuzzLocalEtcd,
 		fuzzNetworking,
 		fuzzJoinConfiguration,
@@ -59,6 +59,9 @@ func fuzzInitConfiguration(obj *kubeadm.InitConfiguration, c fuzz.Continue) {
 			LogDir:    constants.StaticPodAuditPolicyLogDir,
 			LogMaxAge: &v1beta1.DefaultAuditPolicyLogMaxAge,
 		},
+		DNS: kubeadm.DNS{
+			Type: kubeadm.CoreDNS,
+		},
 		CertificatesDir: v1beta1.DefaultCertificatesDir,
 		ClusterName:     v1beta1.DefaultClusterName,
 		Etcd: kubeadm.Etcd{
@@ -107,6 +110,14 @@ func fuzzClusterConfiguration(obj *kubeadm.ClusterConfiguration, c fuzz.Continue
 	}
 }
 
+func fuzzDNS(obj *kubeadm.DNS, c fuzz.Continue) {
+	// This is intentionally not calling c.FuzzNoCustom because DNS struct does not exists in v1alpha3 api
+	// (so no random value will be applied, and this is necessary for getting roundtrip passing)
+
+	// Pinning values for fields that get defaults if fuzz value is empty string or nil
+	obj.Type = kubeadm.CoreDNS
+}
+
 func fuzzAuditPolicyConfiguration(obj *kubeadm.AuditPolicyConfiguration, c fuzz.Continue) {
 	c.FuzzNoCustom(obj)
 
@@ -125,6 +136,10 @@ func fuzzLocalEtcd(obj *kubeadm.LocalEtcd, c fuzz.Continue) {
 
 	// Pinning values for fields that get defaults if fuzz value is empty string or nil (thus making the round trip test fail)
 	obj.DataDir = "foo"
+
+	// Pinning values for fields that does not exists in v1alpha3 api
+	obj.ImageRepository = ""
+	obj.ImageTag = ""
 }
 
 func fuzzNetworking(obj *kubeadm.Networking, c fuzz.Continue) {

cmd/kubeadm/app/apis/kubeadm/types.go

@@ -95,10 +95,16 @@ type ClusterConfiguration struct {
 	// Scheduler contains extra settings for the scheduler control plane component
 	Scheduler ControlPlaneComponent
 
+	// DNS defines the options for the DNS add-on installed in the cluster.
+	DNS DNS
+
 	// CertificatesDir specifies where to store or look for all required certificates.
 	CertificatesDir string
 
-	// ImageRepository is the container registry to pull control plane images from.
+	// ImageRepository sets the container registry to pull images from.
+	// If empty, `k8s.gcr.io` will be used by default; in case of kubernetes version is a CI build (kubernetes version starts with `ci/` or `ci-cross/`)
+	// `gcr.io/kubernetes-ci-images` will be used as a default for control plane components and for kube-proxy, while `k8s.gcr.io`
+	// will be used for all the other images.
 	ImageRepository string
 
 	// CIImageRepository is the container registry for core images generated by CI.
@@ -122,6 +128,8 @@ type ClusterConfiguration struct {
 // ControlPlaneComponent holds settings common to control plane component of the cluster
 type ControlPlaneComponent struct {
 	// ExtraArgs is an extra set of flags to pass to the control plane component.
+	// TODO: This is temporary and ideally we would like to switch all components to
+	// use ComponentConfig + ConfigMaps.
 	ExtraArgs map[string]string
 
 	// ExtraVolumes is an extra set of host volumes, mounted to the control plane component.
@@ -139,6 +147,40 @@ type APIServer struct {
 	TimeoutForControlPlane *metav1.Duration
 }
 
+// DNSAddOnType defines string identifying DNS add-on types
+type DNSAddOnType string
+
+const (
+	// CoreDNS add-on type
+	CoreDNS DNSAddOnType = "CoreDNS"
+
+	// KubeDNS add-on type
+	KubeDNS DNSAddOnType = "kube-dns"
+)
+
+// DNS defines the DNS addon that should be used in the cluster
+type DNS struct {
+	// Type defines the DNS add-on to be used
+	Type DNSAddOnType
+
+	// ImageMeta allows to customize the image used for the DNS component
+	ImageMeta `json:",inline"`
+}
+
+// ImageMeta allows to customize the image used for components that are not
+// originated from the Kubernetes/Kubernetes release process
+type ImageMeta struct {
+	// ImageRepository sets the container registry to pull images from.
+	// if not set, the ImageRepository defined in ClusterConfiguration will be used instead.
+	ImageRepository string
+
+	// ImageTag allows to specify a tag for the image.
+	// In case this value is set, kubeadm does not change automatically the version of the above components during upgrades.
+	ImageTag string
+
+	//TODO: evaluate if we need also a ImageName based on user feedbacks
+}
+
 // ComponentConfigs holds known internal ComponentConfig types for other components
 type ComponentConfigs struct {
 	// Kubelet holds the ComponentConfiguration for the kubelet
@@ -239,11 +281,8 @@ type Etcd struct {
 
 // LocalEtcd describes that kubeadm should run an etcd cluster locally
 type LocalEtcd struct {
-
-	// Image specifies which container image to use for running etcd.
-	// If empty, automatically populated by kubeadm using the image
-	// repository and default etcd version.
-	Image string
+	// ImageMeta allows to customize the container used for etcd
+	ImageMeta `json:",inline"`
 
 	// DataDir is the directory etcd will place its data.
 	// Defaults to "/var/lib/etcd".

cmd/kubeadm/app/apis/kubeadm/v1alpha3/BUILD

@@ -20,6 +20,7 @@ go_library(
     deps = [
         "//cmd/kubeadm/app/apis/kubeadm:go_default_library",
         "//cmd/kubeadm/app/constants:go_default_library",
+        "//cmd/kubeadm/app/features:go_default_library",
         "//cmd/kubeadm/app/images:go_default_library",
         "//cmd/kubeadm/app/util:go_default_library",
         "//staging/src/k8s.io/api/core/v1:go_default_library",
@@ -56,8 +57,6 @@ go_test(
     embed = [":go_default_library"],
     deps = [
         "//cmd/kubeadm/app/apis/kubeadm:go_default_library",
-        "//cmd/kubeadm/app/apis/kubeadm/scheme:go_default_library",
-        "//cmd/kubeadm/test:go_default_library",
         "//vendor/github.com/pkg/errors:go_default_library",
     ],
 )

cmd/kubeadm/app/apis/kubeadm/v1alpha3/conversion.go

@@ -17,16 +17,21 @@ limitations under the License.
 package v1alpha3
 
 import (
-	"github.com/pkg/errors"
+	"regexp"
+	"strings"
 
+	"github.com/pkg/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/conversion"
 	"k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
 	"k8s.io/kubernetes/cmd/kubeadm/app/constants"
+	"k8s.io/kubernetes/cmd/kubeadm/app/features"
 	"k8s.io/kubernetes/cmd/kubeadm/app/images"
 	kubeadmutil "k8s.io/kubernetes/cmd/kubeadm/app/util"
 )
 
+var imageRegEx = regexp.MustCompile(`(?P<repository>.+/)(?P<image>[^:]+)(?P<tag>:.+)`)
+
 func Convert_v1alpha3_InitConfiguration_To_kubeadm_InitConfiguration(in *InitConfiguration, out *kubeadm.InitConfiguration, s conversion.Scope) error {
 	if err := autoConvert_v1alpha3_InitConfiguration_To_kubeadm_InitConfiguration(in, out, s); err != nil {
 		return err
@@ -133,6 +138,14 @@ func Convert_v1alpha3_ClusterConfiguration_To_kubeadm_ClusterConfiguration(in *C
 		return err
 	}
 
+	// converting v1alpha3 featureGate CoreDNS to internal DNS.Type
+	if features.Enabled(in.FeatureGates, features.CoreDNS) {
+		out.DNS.Type = kubeadm.CoreDNS
+	} else {
+		out.DNS.Type = kubeadm.KubeDNS
+	}
+	delete(out.FeatureGates, features.CoreDNS)
+
 	return nil
 }
 
@@ -174,11 +187,19 @@ func Convert_kubeadm_ClusterConfiguration_To_v1alpha3_ClusterConfiguration(in *k
 	}
 
 	if in.UseHyperKubeImage {
-		out.UnifiedControlPlaneImage = images.GetKubeControlPlaneImage("", in)
+		out.UnifiedControlPlaneImage = images.GetKubernetesImage("", in)
 	} else {
 		out.UnifiedControlPlaneImage = ""
 	}
 
+	// converting internal DNS.Type to v1alpha3 featureGate CoreDNS (this is only for getting roundtrip passing, but it is never used in reality)
+	if out.FeatureGates == nil {
+		out.FeatureGates = map[string]bool{}
+	}
+	if in.DNS.Type == kubeadm.KubeDNS {
+		out.FeatureGates[features.CoreDNS] = false
+	}
+
 	return nil
 }
 
@@ -225,5 +246,52 @@ func convertSlice_kubeadm_HostPathMount_To_v1alpha3_HostPathMount(in *[]kubeadm.
 	} else {
 		*out = nil
 	}
+
+	return nil
+}
+
+func Convert_v1alpha3_LocalEtcd_To_kubeadm_LocalEtcd(in *LocalEtcd, out *kubeadm.LocalEtcd, s conversion.Scope) error {
+	if err := autoConvert_v1alpha3_LocalEtcd_To_kubeadm_LocalEtcd(in, out, s); err != nil {
+		return err
+	}
+
+	var err error
+	out.ImageMeta, err = etcdImageToImageMeta(in.Image)
+	return err
+}
+
+func etcdImageToImageMeta(image string) (kubeadm.ImageMeta, error) {
+	// empty image -> empty image meta
+	if image == "" {
+		return kubeadm.ImageMeta{}, nil
+	}
+
+	matches := imageRegEx.FindStringSubmatch(image)
+	if len(matches) != 4 {
+		return kubeadm.ImageMeta{}, errors.New("Conversion Error: kubeadm does not support converting v1alpha3 configurations with etcd image without explicit repository or tag definition. Please fix the image name")
+	}
+
+	imageRepository := strings.TrimSuffix(matches[1], "/")
+	imageName := matches[2]
+	imageTag := strings.TrimPrefix(matches[3], ":")
+
+	if imageName != constants.Etcd {
+		return kubeadm.ImageMeta{}, errors.New("Conversion Error: kubeadm does not support converting v1alpha3 configurations with etcd imageName different than etcd. Please fix the image name")
+	}
+
+	return kubeadm.ImageMeta{
+		ImageRepository: imageRepository,
+		ImageTag:        imageTag,
+	}, nil
+}
+
+func Convert_kubeadm_LocalEtcd_To_v1alpha3_LocalEtcd(in *kubeadm.LocalEtcd, out *LocalEtcd, s conversion.Scope) error {
+	if err := autoConvert_kubeadm_LocalEtcd_To_v1alpha3_LocalEtcd(in, out, s); err != nil {
+		return err
+	}
+
+	// converting internal LocalEtcd.ImageMeta to v1alpha3 LocalEtcd.Image (this is only for getting roundtrip passing, but it is
+	// never used in reality)
+
 	return nil
 }