Merge pull request #59495 from ericchiang/client-auth-exec

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>.

 client-go: add an exec-based client auth provider

Updates https://github.com/kubernetes/features/issues/541
Implements https://github.com/kubernetes/community/pull/1503
Closes https://github.com/kubernetes/kubernetes/issues/57164

```release-note
client-go: alpha support for exec-based credential providers
```

/sig auth
/kind feature

Kubernetes-commit: cb9d6b51556a1677f262e35e4aded0051c424818

vendor/k8s.io/client-go/tools/clientcmd/api/v1/types.go

@@ -113,6 +113,9 @@ type AuthInfo struct {
 	// AuthProvider specifies a custom authentication plugin for the kubernetes cluster.
 	// +optional
 	AuthProvider *AuthProviderConfig `json:"auth-provider,omitempty"`
+	// Exec specifies a custom exec-based authentication plugin for the kubernetes cluster.
+	// +optional
+	Exec *ExecConfig `json:"exec,omitempty"`
 	// Extensions holds additional information. This is useful for extenders so that reads and writes don't clobber unknown fields
 	// +optional
 	Extensions []NamedExtension `json:"extensions,omitempty"`
@@ -169,3 +172,32 @@ type AuthProviderConfig struct {
 	Name   string            `json:"name"`
 	Config map[string]string `json:"config"`
 }
+
+// ExecConfig specifies a command to provide client credentials. The command is exec'd
+// and outputs structured stdout holding credentials.
+//
+// See the client.authentiction.k8s.io API group for specifications of the exact input
+// and output format
+type ExecConfig struct {
+	// Command to execute.
+	Command string `json:"command"`
+	// Arguments to pass to the command when executing it.
+	// +optional
+	Args []string `json:"args"`
+	// Env defines additional environment variables to expose to the process. These
+	// are unioned with the host's environment, as well as variables client-go uses
+	// to pass argument to the plugin.
+	// +optional
+	Env []ExecEnvVar `json:"env"`
+
+	// Preferred input version of the ExecInfo. The returned ExecCredentials MUST use
+	// the same encoding version as the input.
+	APIVersion string `json:"apiVersion,omitempty"`
+}
+
+// ExecEnvVar is used for setting environment variables when executing an exec-based
+// credential plugin.
+type ExecEnvVar struct {
+	Name  string `json:"name"`
+	Value string `json:"value"`
+}

vendor/k8s.io/client-go/tools/clientcmd/api/v1/zz_generated.deepcopy.go

@@ -63,6 +63,15 @@ func (in *AuthInfo) DeepCopyInto(out *AuthInfo) {
 			(*in).DeepCopyInto(*out)
 		}
 	}
+	if in.Exec != nil {
+		in, out := &in.Exec, &out.Exec
+		if *in == nil {
+			*out = nil
+		} else {
+			*out = new(ExecConfig)
+			(*in).DeepCopyInto(*out)
+		}
+	}
 	if in.Extensions != nil {
 		in, out := &in.Extensions, &out.Extensions
 		*out = make([]NamedExtension, len(*in))
@@ -210,6 +219,48 @@ func (in *Context) DeepCopy() *Context {
 	return out
 }
 
+// DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
+func (in *ExecConfig) DeepCopyInto(out *ExecConfig) {
+	*out = *in
+	if in.Args != nil {
+		in, out := &in.Args, &out.Args
+		*out = make([]string, len(*in))
+		copy(*out, *in)
+	}
+	if in.Env != nil {
+		in, out := &in.Env, &out.Env
+		*out = make([]ExecEnvVar, len(*in))
+		copy(*out, *in)
+	}
+	return
+}
+
+// DeepCopy is an autogenerated deepcopy function, copying the receiver, creating a new ExecConfig.
+func (in *ExecConfig) DeepCopy() *ExecConfig {
+	if in == nil {
+		return nil
+	}
+	out := new(ExecConfig)
+	in.DeepCopyInto(out)
+	return out
+}
+
+// DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
+func (in *ExecEnvVar) DeepCopyInto(out *ExecEnvVar) {
+	*out = *in
+	return
+}
+
+// DeepCopy is an autogenerated deepcopy function, copying the receiver, creating a new ExecEnvVar.
+func (in *ExecEnvVar) DeepCopy() *ExecEnvVar {
+	if in == nil {
+		return nil
+	}
+	out := new(ExecEnvVar)
+	in.DeepCopyInto(out)
+	return out
+}
+
 // DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
 func (in *NamedAuthInfo) DeepCopyInto(out *NamedAuthInfo) {
 	*out = *in