Merge pull request #65629 from luxas/kubeadm_add_v1alpha3

Automatic merge from submit-queue (batch tested with PRs 64593, 65117, 65629, 65827, 65686). 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>.

kubeadm: Add a `v1alpha3` API

**What this PR does / why we need it**:
Adds a (now duplicated) v1alpha3 API. Equal to `v1alpha2` now, but will be changed later.
Hopefully we'll graduate this to `v1beta1` during the v1.12 cycle.

**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
ref: kubernetes/kubeadm#911
Depends on:
 - [x] #65776
 - [x] #65628

**Special notes for your reviewer**:

These commits should be reviewed:
 - `Add a duplicated v1alpha3 API`: A pure directory copy of the `v1alpha2` folder, only changed the package name in the Go files
 - `Register the v1alpha3 API in the scheme, and update the roundtrip API tests`, started registering the new API and using it internally
 - `Automated bump from v1alpha2 references to v1alpha3`: Replaced all v1alpha2 references with v1alpha3

**Release note**:

```release-note
kubeadm: Add a `v1alpha3` API.
```
@kubernetes/sig-cluster-lifecycle-pr-reviews

cmd/kubeadm/app/apis/kubeadm/BUILD

@@ -43,6 +43,7 @@ filegroup(
         "//cmd/kubeadm/app/apis/kubeadm/fuzzer:all-srcs",
         "//cmd/kubeadm/app/apis/kubeadm/scheme:all-srcs",
         "//cmd/kubeadm/app/apis/kubeadm/v1alpha2:all-srcs",
+        "//cmd/kubeadm/app/apis/kubeadm/v1alpha3:all-srcs",
         "//cmd/kubeadm/app/apis/kubeadm/validation:all-srcs",
     ],
     tags = ["automanaged"],

cmd/kubeadm/app/apis/kubeadm/scheme/BUILD

@@ -8,6 +8,7 @@ go_library(
     deps = [
         "//cmd/kubeadm/app/apis/kubeadm:go_default_library",
         "//cmd/kubeadm/app/apis/kubeadm/v1alpha2:go_default_library",
+        "//cmd/kubeadm/app/apis/kubeadm/v1alpha3:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/runtime:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/runtime/schema:go_default_library",

cmd/kubeadm/app/apis/kubeadm/scheme/scheme.go

@@ -24,6 +24,7 @@ import (
 	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
 	"k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
 	"k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1alpha2"
+	"k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1alpha3"
 )
 
 // Scheme is the runtime.Scheme to which all kubeadm api types are registered.
@@ -41,5 +42,6 @@ func init() {
 func AddToScheme(scheme *runtime.Scheme) {
 	utilruntime.Must(kubeadm.AddToScheme(scheme))
 	utilruntime.Must(v1alpha2.AddToScheme(scheme))
-	utilruntime.Must(scheme.SetVersionPriority(v1alpha2.SchemeGroupVersion))
+	utilruntime.Must(v1alpha3.AddToScheme(scheme))
+	utilruntime.Must(scheme.SetVersionPriority(v1alpha3.SchemeGroupVersion))
 }

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

@@ -0,0 +1,55 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library", "go_test")
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "bootstraptokenstring.go",
+        "defaults.go",
+        "defaults_unix.go",
+        "defaults_windows.go",
+        "doc.go",
+        "register.go",
+        "types.go",
+        "zz_generated.conversion.go",
+        "zz_generated.deepcopy.go",
+        "zz_generated.defaults.go",
+    ],
+    importpath = "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1alpha3",
+    visibility = ["//visibility:public"],
+    deps = [
+        "//cmd/kubeadm/app/apis/kubeadm:go_default_library",
+        "//cmd/kubeadm/app/constants:go_default_library",
+        "//pkg/kubelet/apis/kubeletconfig/scheme:go_default_library",
+        "//pkg/kubelet/apis/kubeletconfig/v1beta1:go_default_library",
+        "//pkg/proxy/apis/kubeproxyconfig/scheme:go_default_library",
+        "//pkg/proxy/apis/kubeproxyconfig/v1alpha1:go_default_library",
+        "//pkg/util/pointer:go_default_library",
+        "//staging/src/k8s.io/api/core/v1:go_default_library",
+        "//staging/src/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",
+        "//staging/src/k8s.io/apimachinery/pkg/conversion:go_default_library",
+        "//staging/src/k8s.io/apimachinery/pkg/runtime:go_default_library",
+        "//staging/src/k8s.io/apimachinery/pkg/runtime/schema:go_default_library",
+        "//staging/src/k8s.io/client-go/tools/bootstrap/token/api:go_default_library",
+        "//staging/src/k8s.io/client-go/tools/bootstrap/token/util:go_default_library",
+    ],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+    visibility = ["//visibility:public"],
+)
+
+go_test(
+    name = "go_default_test",
+    srcs = ["bootstraptokenstring_test.go"],
+    embed = [":go_default_library"],
+)

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

@@ -0,0 +1,90 @@
+/*
+Copyright 2018 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 v1alpha2 holds the external kubeadm API types of version v1alpha2
+// Note: This file should be kept in sync with the similar one for the internal API
+// TODO: The BootstrapTokenString object should move out to either k8s.io/client-go or k8s.io/api in the future
+// (probably as part of Bootstrap Tokens going GA). It should not be staged under the kubeadm API as it is now.
+package v1alpha3
+
+import (
+	"fmt"
+	"strings"
+
+	bootstrapapi "k8s.io/client-go/tools/bootstrap/token/api"
+	bootstraputil "k8s.io/client-go/tools/bootstrap/token/util"
+)
+
+// BootstrapTokenString is a token of the format abcdef.abcdef0123456789 that is used
+// for both validation of the practically of the API server from a joining node's point
+// of view and as an authentication method for the node in the bootstrap phase of
+// "kubeadm join". This token is and should be short-lived
+type BootstrapTokenString struct {
+	ID     string
+	Secret string
+}
+
+// MarshalJSON implements the json.Marshaler interface.
+func (bts BootstrapTokenString) MarshalJSON() ([]byte, error) {
+	return []byte(fmt.Sprintf(`"%s"`, bts.String())), nil
+}
+
+// UnmarshalJSON implements the json.Unmarshaller interface.
+func (bts *BootstrapTokenString) UnmarshalJSON(b []byte) error {
+	// If the token is represented as "", just return quickly without an error
+	if len(b) == 0 {
+		return nil
+	}
+
+	// Remove unnecessary " characters coming from the JSON parser
+	token := strings.Replace(string(b), `"`, ``, -1)
+	// Convert the string Token to a BootstrapTokenString object
+	newbts, err := NewBootstrapTokenString(token)
+	if err != nil {
+		return err
+	}
+	bts.ID = newbts.ID
+	bts.Secret = newbts.Secret
+	return nil
+}
+
+// String returns the string representation of the BootstrapTokenString
+func (bts BootstrapTokenString) String() string {
+	if len(bts.ID) > 0 && len(bts.Secret) > 0 {
+		return bootstraputil.TokenFromIDAndSecret(bts.ID, bts.Secret)
+	}
+	return ""
+}
+
+// NewBootstrapTokenString converts the given Bootstrap Token as a string
+// to the BootstrapTokenString object used for serialization/deserialization
+// and internal usage. It also automatically validates that the given token
+// is of the right format
+func NewBootstrapTokenString(token string) (*BootstrapTokenString, error) {
+	substrs := bootstraputil.BootstrapTokenRegexp.FindStringSubmatch(token)
+	// TODO: Add a constant for the 3 value here, and explain better why it's needed (other than because how the regexp parsin works)
+	if len(substrs) != 3 {
+		return nil, fmt.Errorf("the bootstrap token %q was not of the form %q", token, bootstrapapi.BootstrapTokenPattern)
+	}
+
+	return &BootstrapTokenString{ID: substrs[1], Secret: substrs[2]}, nil
+}
+
+// NewBootstrapTokenStringFromIDAndSecret is a wrapper around NewBootstrapTokenString
+// that allows the caller to specify the ID and Secret separately
+func NewBootstrapTokenStringFromIDAndSecret(id, secret string) (*BootstrapTokenString, error) {
+	return NewBootstrapTokenString(bootstraputil.TokenFromIDAndSecret(id, secret))
+}