diff --git a/metrics-server/vendor/k8s.io/client-go/util/buffer/ring_growing.go b/metrics-server/vendor/k8s.io/client-go/util/buffer/ring_growing.go
new file mode 100644
index 0000000..86965a5
--- /dev/null
+++ b/metrics-server/vendor/k8s.io/client-go/util/buffer/ring_growing.go
@@ -0,0 +1,72 @@
+/*
+Copyright 2017 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 buffer
+
+// RingGrowing is a growing ring buffer.
+// Not thread safe.
+type RingGrowing struct {
+	data     []interface{}
+	n        int // Size of Data
+	beg      int // First available element
+	readable int // Number of data items available
+}
+
+// NewRingGrowing constructs a new RingGrowing instance with provided parameters.
+func NewRingGrowing(initialSize int) *RingGrowing {
+	return &RingGrowing{
+		data: make([]interface{}, initialSize),
+		n:    initialSize,
+	}
+}
+
+// ReadOne reads (consumes) first item from the buffer if it is available, otherwise returns false.
+func (r *RingGrowing) ReadOne() (data interface{}, ok bool) {
+	if r.readable == 0 {
+		return nil, false
+	}
+	r.readable--
+	element := r.data[r.beg]
+	r.data[r.beg] = nil // Remove reference to the object to help GC
+	if r.beg == r.n-1 {
+		// Was the last element
+		r.beg = 0
+	} else {
+		r.beg++
+	}
+	return element, true
+}
+
+// WriteOne adds an item to the end of the buffer, growing it if it is full.
+func (r *RingGrowing) WriteOne(data interface{}) {
+	if r.readable == r.n {
+		// Time to grow
+		newN := r.n * 2
+		newData := make([]interface{}, newN)
+		to := r.beg + r.readable
+		if to <= r.n {
+			copy(newData, r.data[r.beg:to])
+		} else {
+			copied := copy(newData, r.data[r.beg:])
+			copy(newData[copied:], r.data[:(to%r.n)])
+		}
+		r.beg = 0
+		r.data = newData
+		r.n = newN
+	}
+	r.data[(r.readable+r.beg)%r.n] = data
+	r.readable++
+}
diff --git a/metrics-server/vendor/k8s.io/client-go/util/cert/cert.go b/metrics-server/vendor/k8s.io/client-go/util/cert/cert.go
new file mode 100644
index 0000000..fb7f5fa
--- /dev/null
+++ b/metrics-server/vendor/k8s.io/client-go/util/cert/cert.go
@@ -0,0 +1,245 @@
+/*
+Copyright 2014 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 cert
+
+import (
+	"bytes"
+	"crypto/ecdsa"
+	"crypto/elliptic"
+	cryptorand "crypto/rand"
+	"crypto/rsa"
+	"crypto/x509"
+	"crypto/x509/pkix"
+	"encoding/pem"
+	"errors"
+	"fmt"
+	"math"
+	"math/big"
+	"net"
+	"time"
+)
+
+const (
+	rsaKeySize   = 2048
+	duration365d = time.Hour * 24 * 365
+)
+
+// Config contains the basic fields required for creating a certificate
+type Config struct {
+	CommonName   string
+	Organization []string
+	AltNames     AltNames
+	Usages       []x509.ExtKeyUsage
+}
+
+// AltNames contains the domain names and IP addresses that will be added
+// to the API Server's x509 certificate SubAltNames field. The values will
+// be passed directly to the x509.Certificate object.
+type AltNames struct {
+	DNSNames []string
+	IPs      []net.IP
+}
+
+// NewPrivateKey creates an RSA private key
+func NewPrivateKey() (*rsa.PrivateKey, error) {
+	return rsa.GenerateKey(cryptorand.Reader, rsaKeySize)
+}
+
+// NewSelfSignedCACert creates a CA certificate
+func NewSelfSignedCACert(cfg Config, key *rsa.PrivateKey) (*x509.Certificate, error) {
+	now := time.Now()
+	tmpl := x509.Certificate{
+		SerialNumber: new(big.Int).SetInt64(0),
+		Subject: pkix.Name{
+			CommonName:   cfg.CommonName,
+			Organization: cfg.Organization,
+		},
+		NotBefore:             now.UTC(),
+		NotAfter:              now.Add(duration365d * 10).UTC(),
+		KeyUsage:              x509.KeyUsageKeyEncipherment | x509.KeyUsageDigitalSignature | x509.KeyUsageCertSign,
+		BasicConstraintsValid: true,
+		IsCA: true,
+	}
+
+	certDERBytes, err := x509.CreateCertificate(cryptorand.Reader, &tmpl, &tmpl, key.Public(), key)
+	if err != nil {
+		return nil, err
+	}
+	return x509.ParseCertificate(certDERBytes)
+}
+
+// NewSignedCert creates a signed certificate using the given CA certificate and key
+func NewSignedCert(cfg Config, key *rsa.PrivateKey, caCert *x509.Certificate, caKey *rsa.PrivateKey) (*x509.Certificate, error) {
+	serial, err := cryptorand.Int(cryptorand.Reader, new(big.Int).SetInt64(math.MaxInt64))
+	if err != nil {
+		return nil, err
+	}
+	if len(cfg.CommonName) == 0 {
+		return nil, errors.New("must specify a CommonName")
+	}
+	if len(cfg.Usages) == 0 {
+		return nil, errors.New("must specify at least one ExtKeyUsage")
+	}
+
+	certTmpl := x509.Certificate{
+		Subject: pkix.Name{
+			CommonName:   cfg.CommonName,
+			Organization: cfg.Organization,
+		},
+		DNSNames:     cfg.AltNames.DNSNames,
+		IPAddresses:  cfg.AltNames.IPs,
+		SerialNumber: serial,
+		NotBefore:    caCert.NotBefore,
+		NotAfter:     time.Now().Add(duration365d).UTC(),
+		KeyUsage:     x509.KeyUsageKeyEncipherment | x509.KeyUsageDigitalSignature,
+		ExtKeyUsage:  cfg.Usages,
+	}
+	certDERBytes, err := x509.CreateCertificate(cryptorand.Reader, &certTmpl, caCert, key.Public(), caKey)
+	if err != nil {
+		return nil, err
+	}
+	return x509.ParseCertificate(certDERBytes)
+}
+
+// MakeEllipticPrivateKeyPEM creates an ECDSA private key
+func MakeEllipticPrivateKeyPEM() ([]byte, error) {
+	privateKey, err := ecdsa.GenerateKey(elliptic.P256(), cryptorand.Reader)
+	if err != nil {
+		return nil, err
+	}
+
+	derBytes, err := x509.MarshalECPrivateKey(privateKey)
+	if err != nil {
+		return nil, err
+	}
+
+	privateKeyPemBlock := &pem.Block{
+		Type:  ECPrivateKeyBlockType,
+		Bytes: derBytes,
+	}
+	return pem.EncodeToMemory(privateKeyPemBlock), nil
+}
+
+// GenerateSelfSignedCertKey creates a self-signed certificate and key for the given host.
+// Host may be an IP or a DNS name
+// You may also specify additional subject alt names (either ip or dns names) for the certificate
+func GenerateSelfSignedCertKey(host string, alternateIPs []net.IP, alternateDNS []string) ([]byte, []byte, error) {
+	caKey, err := rsa.GenerateKey(cryptorand.Reader, 2048)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	caTemplate := x509.Certificate{
+		SerialNumber: big.NewInt(1),
+		Subject: pkix.Name{
+			CommonName: fmt.Sprintf("%s-ca@%d", host, time.Now().Unix()),
+		},
+		NotBefore: time.Now(),
+		NotAfter:  time.Now().Add(time.Hour * 24 * 365),
+
+		KeyUsage:              x509.KeyUsageKeyEncipherment | x509.KeyUsageDigitalSignature | x509.KeyUsageCertSign,
+		BasicConstraintsValid: true,
+		IsCA: true,
+	}
+
+	caDERBytes, err := x509.CreateCertificate(cryptorand.Reader, &caTemplate, &caTemplate, &caKey.PublicKey, caKey)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	caCertificate, err := x509.ParseCertificate(caDERBytes)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	priv, err := rsa.GenerateKey(cryptorand.Reader, 2048)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	template := x509.Certificate{
+		SerialNumber: big.NewInt(2),
+		Subject: pkix.Name{
+			CommonName: fmt.Sprintf("%s@%d", host, time.Now().Unix()),
+		},
+		NotBefore: time.Now(),
+		NotAfter:  time.Now().Add(time.Hour * 24 * 365),
+
+		KeyUsage:              x509.KeyUsageKeyEncipherment | x509.KeyUsageDigitalSignature,
+		ExtKeyUsage:           []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth},
+		BasicConstraintsValid: true,
+	}
+
+	if ip := net.ParseIP(host); ip != nil {
+		template.IPAddresses = append(template.IPAddresses, ip)
+	} else {
+		template.DNSNames = append(template.DNSNames, host)
+	}
+
+	template.IPAddresses = append(template.IPAddresses, alternateIPs...)
+	template.DNSNames = append(template.DNSNames, alternateDNS...)
+
+	derBytes, err := x509.CreateCertificate(cryptorand.Reader, &template, caCertificate, &priv.PublicKey, caKey)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// Generate cert, followed by ca
+	certBuffer := bytes.Buffer{}
+	if err := pem.Encode(&certBuffer, &pem.Block{Type: CertificateBlockType, Bytes: derBytes}); err != nil {
+		return nil, nil, err
+	}
+	if err := pem.Encode(&certBuffer, &pem.Block{Type: CertificateBlockType, Bytes: caDERBytes}); err != nil {
+		return nil, nil, err
+	}
+
+	// Generate key
+	keyBuffer := bytes.Buffer{}
+	if err := pem.Encode(&keyBuffer, &pem.Block{Type: RSAPrivateKeyBlockType, Bytes: x509.MarshalPKCS1PrivateKey(priv)}); err != nil {
+		return nil, nil, err
+	}
+
+	return certBuffer.Bytes(), keyBuffer.Bytes(), nil
+}
+
+// FormatBytesCert receives byte array certificate and formats in human-readable format
+func FormatBytesCert(cert []byte) (string, error) {
+	block, _ := pem.Decode(cert)
+	c, err := x509.ParseCertificate(block.Bytes)
+	if err != nil {
+		return "", fmt.Errorf("failed to parse certificate [%v]", err)
+	}
+	return FormatCert(c), nil
+}
+
+// FormatCert receives certificate and formats in human-readable format
+func FormatCert(c *x509.Certificate) string {
+	var ips []string
+	for _, ip := range c.IPAddresses {
+		ips = append(ips, ip.String())
+	}
+	altNames := append(ips, c.DNSNames...)
+	res := fmt.Sprintf(
+		"Issuer: CN=%s | Subject: CN=%s | CA: %t\n",
+		c.Issuer.CommonName, c.Subject.CommonName, c.IsCA,
+	)
+	res += fmt.Sprintf("Not before: %s Not After: %s", c.NotBefore, c.NotAfter)
+	if len(altNames) > 0 {
+		res += fmt.Sprintf("\nAlternate Names: %v", altNames)
+	}
+	return res
+}
diff --git a/metrics-server/vendor/k8s.io/client-go/util/cert/csr.go b/metrics-server/vendor/k8s.io/client-go/util/cert/csr.go
new file mode 100644
index 0000000..39a6751
--- /dev/null
+++ b/metrics-server/vendor/k8s.io/client-go/util/cert/csr.go
@@ -0,0 +1,75 @@
+/*
+Copyright 2016 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 cert
+
+import (
+	cryptorand "crypto/rand"
+	"crypto/rsa"
+	"crypto/x509"
+	"crypto/x509/pkix"
+	"encoding/pem"
+	"net"
+)
+
+// MakeCSR generates a PEM-encoded CSR using the supplied private key, subject, and SANs.
+// All key types that are implemented via crypto.Signer are supported (This includes *rsa.PrivateKey and *ecdsa.PrivateKey.)
+func MakeCSR(privateKey interface{}, subject *pkix.Name, dnsSANs []string, ipSANs []net.IP) (csr []byte, err error) {
+	template := &x509.CertificateRequest{
+		Subject:     *subject,
+		DNSNames:    dnsSANs,
+		IPAddresses: ipSANs,
+	}
+
+	return MakeCSRFromTemplate(privateKey, template)
+}
+
+// MakeCSRFromTemplate generates a PEM-encoded CSR using the supplied private
+// key and certificate request as a template. All key types that are
+// implemented via crypto.Signer are supported (This includes *rsa.PrivateKey
+// and *ecdsa.PrivateKey.)
+func MakeCSRFromTemplate(privateKey interface{}, template *x509.CertificateRequest) ([]byte, error) {
+	t := *template
+	t.SignatureAlgorithm = sigType(privateKey)
+
+	csrDER, err := x509.CreateCertificateRequest(cryptorand.Reader, &t, privateKey)
+	if err != nil {
+		return nil, err
+	}
+
+	csrPemBlock := &pem.Block{
+		Type:  CertificateRequestBlockType,
+		Bytes: csrDER,
+	}
+
+	return pem.EncodeToMemory(csrPemBlock), nil
+}
+
+func sigType(privateKey interface{}) x509.SignatureAlgorithm {
+	// Customize the signature for RSA keys, depending on the key size
+	if privateKey, ok := privateKey.(*rsa.PrivateKey); ok {
+		keySize := privateKey.N.BitLen()
+		switch {
+		case keySize >= 4096:
+			return x509.SHA512WithRSA
+		case keySize >= 3072:
+			return x509.SHA384WithRSA
+		default:
+			return x509.SHA256WithRSA
+		}
+	}
+	return x509.UnknownSignatureAlgorithm
+}
diff --git a/metrics-server/vendor/k8s.io/client-go/util/cert/io.go b/metrics-server/vendor/k8s.io/client-go/util/cert/io.go
new file mode 100644
index 0000000..a57bf09
--- /dev/null
+++ b/metrics-server/vendor/k8s.io/client-go/util/cert/io.go
@@ -0,0 +1,193 @@
+/*
+Copyright 2014 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 cert
+
+import (
+	"crypto"
+	"crypto/ecdsa"
+	"crypto/rsa"
+	"crypto/x509"
+	"encoding/pem"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+)
+
+// CanReadCertAndKey returns true if the certificate and key files already exists,
+// otherwise returns false. If lost one of cert and key, returns error.
+func CanReadCertAndKey(certPath, keyPath string) (bool, error) {
+	certReadable := canReadFile(certPath)
+	keyReadable := canReadFile(keyPath)
+
+	if certReadable == false && keyReadable == false {
+		return false, nil
+	}
+
+	if certReadable == false {
+		return false, fmt.Errorf("error reading %s, certificate and key must be supplied as a pair", certPath)
+	}
+
+	if keyReadable == false {
+		return false, fmt.Errorf("error reading %s, certificate and key must be supplied as a pair", keyPath)
+	}
+
+	return true, nil
+}
+
+// If the file represented by path exists and
+// readable, returns true otherwise returns false.
+func canReadFile(path string) bool {
+	f, err := os.Open(path)
+	if err != nil {
+		return false
+	}
+
+	defer f.Close()
+
+	return true
+}
+
+// WriteCert writes the pem-encoded certificate data to certPath.
+// The certificate file will be created with file mode 0644.
+// If the certificate file already exists, it will be overwritten.
+// The parent directory of the certPath will be created as needed with file mode 0755.
+func WriteCert(certPath string, data []byte) error {
+	if err := os.MkdirAll(filepath.Dir(certPath), os.FileMode(0755)); err != nil {
+		return err
+	}
+	return ioutil.WriteFile(certPath, data, os.FileMode(0644))
+}
+
+// WriteKey writes the pem-encoded key data to keyPath.
+// The key file will be created with file mode 0600.
+// If the key file already exists, it will be overwritten.
+// The parent directory of the keyPath will be created as needed with file mode 0755.
+func WriteKey(keyPath string, data []byte) error {
+	if err := os.MkdirAll(filepath.Dir(keyPath), os.FileMode(0755)); err != nil {
+		return err
+	}
+	return ioutil.WriteFile(keyPath, data, os.FileMode(0600))
+}
+
+// LoadOrGenerateKeyFile looks for a key in the file at the given path. If it
+// can't find one, it will generate a new key and store it there.
+func LoadOrGenerateKeyFile(keyPath string) (data []byte, wasGenerated bool, err error) {
+	loadedData, err := ioutil.ReadFile(keyPath)
+	// Call verifyKeyData to ensure the file wasn't empty/corrupt.
+	if err == nil && verifyKeyData(loadedData) {
+		return loadedData, false, err
+	}
+	if !os.IsNotExist(err) {
+		return nil, false, fmt.Errorf("error loading key from %s: %v", keyPath, err)
+	}
+
+	generatedData, err := MakeEllipticPrivateKeyPEM()
+	if err != nil {
+		return nil, false, fmt.Errorf("error generating key: %v", err)
+	}
+	if err := WriteKey(keyPath, generatedData); err != nil {
+		return nil, false, fmt.Errorf("error writing key to %s: %v", keyPath, err)
+	}
+	return generatedData, true, nil
+}
+
+// MarshalPrivateKeyToPEM converts a known private key type of RSA or ECDSA to
+// a PEM encoded block or returns an error.
+func MarshalPrivateKeyToPEM(privateKey crypto.PrivateKey) ([]byte, error) {
+	switch t := privateKey.(type) {
+	case *ecdsa.PrivateKey:
+		derBytes, err := x509.MarshalECPrivateKey(t)
+		if err != nil {
+			return nil, err
+		}
+		privateKeyPemBlock := &pem.Block{
+			Type:  ECPrivateKeyBlockType,
+			Bytes: derBytes,
+		}
+		return pem.EncodeToMemory(privateKeyPemBlock), nil
+	case *rsa.PrivateKey:
+		return EncodePrivateKeyPEM(t), nil
+	default:
+		return nil, fmt.Errorf("private key is not a recognized type: %T", privateKey)
+	}
+}
+
+// NewPool returns an x509.CertPool containing the certificates in the given PEM-encoded file.
+// Returns an error if the file could not be read, a certificate could not be parsed, or if the file does not contain any certificates
+func NewPool(filename string) (*x509.CertPool, error) {
+	certs, err := CertsFromFile(filename)
+	if err != nil {
+		return nil, err
+	}
+	pool := x509.NewCertPool()
+	for _, cert := range certs {
+		pool.AddCert(cert)
+	}
+	return pool, nil
+}
+
+// CertsFromFile returns the x509.Certificates contained in the given PEM-encoded file.
+// Returns an error if the file could not be read, a certificate could not be parsed, or if the file does not contain any certificates
+func CertsFromFile(file string) ([]*x509.Certificate, error) {
+	pemBlock, err := ioutil.ReadFile(file)
+	if err != nil {
+		return nil, err
+	}
+	certs, err := ParseCertsPEM(pemBlock)
+	if err != nil {
+		return nil, fmt.Errorf("error reading %s: %s", file, err)
+	}
+	return certs, nil
+}
+
+// PrivateKeyFromFile returns the private key in rsa.PrivateKey or ecdsa.PrivateKey format from a given PEM-encoded file.
+// Returns an error if the file could not be read or if the private key could not be parsed.
+func PrivateKeyFromFile(file string) (interface{}, error) {
+	data, err := ioutil.ReadFile(file)
+	if err != nil {
+		return nil, err
+	}
+	key, err := ParsePrivateKeyPEM(data)
+	if err != nil {
+		return nil, fmt.Errorf("error reading private key file %s: %v", file, err)
+	}
+	return key, nil
+}
+
+// PublicKeysFromFile returns the public keys in rsa.PublicKey or ecdsa.PublicKey format from a given PEM-encoded file.
+// Reads public keys from both public and private key files.
+func PublicKeysFromFile(file string) ([]interface{}, error) {
+	data, err := ioutil.ReadFile(file)
+	if err != nil {
+		return nil, err
+	}
+	keys, err := ParsePublicKeysPEM(data)
+	if err != nil {
+		return nil, fmt.Errorf("error reading public key file %s: %v", file, err)
+	}
+	return keys, nil
+}
+
+// verifyKeyData returns true if the provided data appears to be a valid private key.
+func verifyKeyData(data []byte) bool {
+	if len(data) == 0 {
+		return false
+	}
+	_, err := ParsePrivateKeyPEM(data)
+	return err == nil
+}
diff --git a/metrics-server/vendor/k8s.io/client-go/util/cert/pem.go b/metrics-server/vendor/k8s.io/client-go/util/cert/pem.go
new file mode 100644
index 0000000..b99e366
--- /dev/null
+++ b/metrics-server/vendor/k8s.io/client-go/util/cert/pem.go
@@ -0,0 +1,269 @@
+/*
+Copyright 2014 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 cert
+
+import (
+	"crypto/ecdsa"
+	"crypto/rsa"
+	"crypto/x509"
+	"encoding/pem"
+	"errors"
+	"fmt"
+)
+
+const (
+	// ECPrivateKeyBlockType is a possible value for pem.Block.Type.
+	ECPrivateKeyBlockType = "EC PRIVATE KEY"
+	// RSAPrivateKeyBlockType is a possible value for pem.Block.Type.
+	RSAPrivateKeyBlockType = "RSA PRIVATE KEY"
+	// PrivateKeyBlockType is a possible value for pem.Block.Type.
+	PrivateKeyBlockType = "PRIVATE KEY"
+	// PublicKeyBlockType is a possible value for pem.Block.Type.
+	PublicKeyBlockType = "PUBLIC KEY"
+	// CertificateBlockType is a possible value for pem.Block.Type.
+	CertificateBlockType = "CERTIFICATE"
+	// CertificateRequestBlockType is a possible value for pem.Block.Type.
+	CertificateRequestBlockType = "CERTIFICATE REQUEST"
+)
+
+// EncodePublicKeyPEM returns PEM-encoded public data
+func EncodePublicKeyPEM(key *rsa.PublicKey) ([]byte, error) {
+	der, err := x509.MarshalPKIXPublicKey(key)
+	if err != nil {
+		return []byte{}, err
+	}
+	block := pem.Block{
+		Type:  PublicKeyBlockType,
+		Bytes: der,
+	}
+	return pem.EncodeToMemory(&block), nil
+}
+
+// EncodePrivateKeyPEM returns PEM-encoded private key data
+func EncodePrivateKeyPEM(key *rsa.PrivateKey) []byte {
+	block := pem.Block{
+		Type:  RSAPrivateKeyBlockType,
+		Bytes: x509.MarshalPKCS1PrivateKey(key),
+	}
+	return pem.EncodeToMemory(&block)
+}
+
+// EncodeCertPEM returns PEM-endcoded certificate data
+func EncodeCertPEM(cert *x509.Certificate) []byte {
+	block := pem.Block{
+		Type:  CertificateBlockType,
+		Bytes: cert.Raw,
+	}
+	return pem.EncodeToMemory(&block)
+}
+
+// ParsePrivateKeyPEM returns a private key parsed from a PEM block in the supplied data.
+// Recognizes PEM blocks for "EC PRIVATE KEY", "RSA PRIVATE KEY", or "PRIVATE KEY"
+func ParsePrivateKeyPEM(keyData []byte) (interface{}, error) {
+	var privateKeyPemBlock *pem.Block
+	for {
+		privateKeyPemBlock, keyData = pem.Decode(keyData)
+		if privateKeyPemBlock == nil {
+			break
+		}
+
+		switch privateKeyPemBlock.Type {
+		case ECPrivateKeyBlockType:
+			// ECDSA Private Key in ASN.1 format
+			if key, err := x509.ParseECPrivateKey(privateKeyPemBlock.Bytes); err == nil {
+				return key, nil
+			}
+		case RSAPrivateKeyBlockType:
+			// RSA Private Key in PKCS#1 format
+			if key, err := x509.ParsePKCS1PrivateKey(privateKeyPemBlock.Bytes); err == nil {
+				return key, nil
+			}
+		case PrivateKeyBlockType:
+			// RSA or ECDSA Private Key in unencrypted PKCS#8 format
+			if key, err := x509.ParsePKCS8PrivateKey(privateKeyPemBlock.Bytes); err == nil {
+				return key, nil
+			}
+		}
+
+		// tolerate non-key PEM blocks for compatibility with things like "EC PARAMETERS" blocks
+		// originally, only the first PEM block was parsed and expected to be a key block
+	}
+
+	// we read all the PEM blocks and didn't recognize one
+	return nil, fmt.Errorf("data does not contain a valid RSA or ECDSA private key")
+}
+
+// ParsePublicKeysPEM is a helper function for reading an array of rsa.PublicKey or ecdsa.PublicKey from a PEM-encoded byte array.
+// Reads public keys from both public and private key files.
+func ParsePublicKeysPEM(keyData []byte) ([]interface{}, error) {
+	var block *pem.Block
+	keys := []interface{}{}
+	for {
+		// read the next block
+		block, keyData = pem.Decode(keyData)
+		if block == nil {
+			break
+		}
+
+		// test block against parsing functions
+		if privateKey, err := parseRSAPrivateKey(block.Bytes); err == nil {
+			keys = append(keys, &privateKey.PublicKey)
+			continue
+		}
+		if publicKey, err := parseRSAPublicKey(block.Bytes); err == nil {
+			keys = append(keys, publicKey)
+			continue
+		}
+		if privateKey, err := parseECPrivateKey(block.Bytes); err == nil {
+			keys = append(keys, &privateKey.PublicKey)
+			continue
+		}
+		if publicKey, err := parseECPublicKey(block.Bytes); err == nil {
+			keys = append(keys, publicKey)
+			continue
+		}
+
+		// tolerate non-key PEM blocks for backwards compatibility
+		// originally, only the first PEM block was parsed and expected to be a key block
+	}
+
+	if len(keys) == 0 {
+		return nil, fmt.Errorf("data does not contain any valid RSA or ECDSA public keys")
+	}
+	return keys, nil
+}
+
+// ParseCertsPEM returns the x509.Certificates contained in the given PEM-encoded byte array
+// Returns an error if a certificate could not be parsed, or if the data does not contain any certificates
+func ParseCertsPEM(pemCerts []byte) ([]*x509.Certificate, error) {
+	ok := false
+	certs := []*x509.Certificate{}
+	for len(pemCerts) > 0 {
+		var block *pem.Block
+		block, pemCerts = pem.Decode(pemCerts)
+		if block == nil {
+			break
+		}
+		// Only use PEM "CERTIFICATE" blocks without extra headers
+		if block.Type != CertificateBlockType || len(block.Headers) != 0 {
+			continue
+		}
+
+		cert, err := x509.ParseCertificate(block.Bytes)
+		if err != nil {
+			return certs, err
+		}
+
+		certs = append(certs, cert)
+		ok = true
+	}
+
+	if !ok {
+		return certs, errors.New("data does not contain any valid RSA or ECDSA certificates")
+	}
+	return certs, nil
+}
+
+// parseRSAPublicKey parses a single RSA public key from the provided data
+func parseRSAPublicKey(data []byte) (*rsa.PublicKey, error) {
+	var err error
+
+	// Parse the key
+	var parsedKey interface{}
+	if parsedKey, err = x509.ParsePKIXPublicKey(data); err != nil {
+		if cert, err := x509.ParseCertificate(data); err == nil {
+			parsedKey = cert.PublicKey
+		} else {
+			return nil, err
+		}
+	}
+
+	// Test if parsed key is an RSA Public Key
+	var pubKey *rsa.PublicKey
+	var ok bool
+	if pubKey, ok = parsedKey.(*rsa.PublicKey); !ok {
+		return nil, fmt.Errorf("data doesn't contain valid RSA Public Key")
+	}
+
+	return pubKey, nil
+}
+
+// parseRSAPrivateKey parses a single RSA private key from the provided data
+func parseRSAPrivateKey(data []byte) (*rsa.PrivateKey, error) {
+	var err error
+
+	// Parse the key
+	var parsedKey interface{}
+	if parsedKey, err = x509.ParsePKCS1PrivateKey(data); err != nil {
+		if parsedKey, err = x509.ParsePKCS8PrivateKey(data); err != nil {
+			return nil, err
+		}
+	}
+
+	// Test if parsed key is an RSA Private Key
+	var privKey *rsa.PrivateKey
+	var ok bool
+	if privKey, ok = parsedKey.(*rsa.PrivateKey); !ok {
+		return nil, fmt.Errorf("data doesn't contain valid RSA Private Key")
+	}
+
+	return privKey, nil
+}
+
+// parseECPublicKey parses a single ECDSA public key from the provided data
+func parseECPublicKey(data []byte) (*ecdsa.PublicKey, error) {
+	var err error
+
+	// Parse the key
+	var parsedKey interface{}
+	if parsedKey, err = x509.ParsePKIXPublicKey(data); err != nil {
+		if cert, err := x509.ParseCertificate(data); err == nil {
+			parsedKey = cert.PublicKey
+		} else {
+			return nil, err
+		}
+	}
+
+	// Test if parsed key is an ECDSA Public Key
+	var pubKey *ecdsa.PublicKey
+	var ok bool
+	if pubKey, ok = parsedKey.(*ecdsa.PublicKey); !ok {
+		return nil, fmt.Errorf("data doesn't contain valid ECDSA Public Key")
+	}
+
+	return pubKey, nil
+}
+
+// parseECPrivateKey parses a single ECDSA private key from the provided data
+func parseECPrivateKey(data []byte) (*ecdsa.PrivateKey, error) {
+	var err error
+
+	// Parse the key
+	var parsedKey interface{}
+	if parsedKey, err = x509.ParseECPrivateKey(data); err != nil {
+		return nil, err
+	}
+
+	// Test if parsed key is an ECDSA Private Key
+	var privKey *ecdsa.PrivateKey
+	var ok bool
+	if privKey, ok = parsedKey.(*ecdsa.PrivateKey); !ok {
+		return nil, fmt.Errorf("data doesn't contain valid ECDSA Private Key")
+	}
+
+	return privKey, nil
+}
diff --git a/metrics-server/vendor/k8s.io/client-go/util/connrotation/connrotation.go b/metrics-server/vendor/k8s.io/client-go/util/connrotation/connrotation.go
new file mode 100644
index 0000000..235a9e0
--- /dev/null
+++ b/metrics-server/vendor/k8s.io/client-go/util/connrotation/connrotation.go
@@ -0,0 +1,105 @@
+/*
+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 connrotation implements a connection dialer that tracks and can close
+// all created connections.
+//
+// This is used for credential rotation of long-lived connections, when there's
+// no way to re-authenticate on a live connection.
+package connrotation
+
+import (
+	"context"
+	"net"
+	"sync"
+)
+
+// DialFunc is a shorthand for signature of net.DialContext.
+type DialFunc func(ctx context.Context, network, address string) (net.Conn, error)
+
+// Dialer opens connections through Dial and tracks them.
+type Dialer struct {
+	dial DialFunc
+
+	mu    sync.Mutex
+	conns map[*closableConn]struct{}
+}
+
+// NewDialer creates a new Dialer instance.
+//
+// If dial is not nil, it will be used to create new underlying connections.
+// Otherwise net.DialContext is used.
+func NewDialer(dial DialFunc) *Dialer {
+	return &Dialer{
+		dial:  dial,
+		conns: make(map[*closableConn]struct{}),
+	}
+}
+
+// CloseAll forcibly closes all tracked connections.
+//
+// Note: new connections may get created before CloseAll returns.
+func (d *Dialer) CloseAll() {
+	d.mu.Lock()
+	conns := d.conns
+	d.conns = make(map[*closableConn]struct{})
+	d.mu.Unlock()
+
+	for conn := range conns {
+		conn.Close()
+	}
+}
+
+// Dial creates a new tracked connection.
+func (d *Dialer) Dial(network, address string) (net.Conn, error) {
+	return d.DialContext(context.Background(), network, address)
+}
+
+// DialContext creates a new tracked connection.
+func (d *Dialer) DialContext(ctx context.Context, network, address string) (net.Conn, error) {
+	conn, err := d.dial(ctx, network, address)
+	if err != nil {
+		return nil, err
+	}
+
+	closable := &closableConn{Conn: conn}
+
+	// Start tracking the connection
+	d.mu.Lock()
+	d.conns[closable] = struct{}{}
+	d.mu.Unlock()
+
+	// When the connection is closed, remove it from the map. This will
+	// be no-op if the connection isn't in the map, e.g. if CloseAll()
+	// is called.
+	closable.onClose = func() {
+		d.mu.Lock()
+		delete(d.conns, closable)
+		d.mu.Unlock()
+	}
+
+	return closable, nil
+}
+
+type closableConn struct {
+	onClose func()
+	net.Conn
+}
+
+func (c *closableConn) Close() error {
+	go c.onClose()
+	return c.Conn.Close()
+}
diff --git a/metrics-server/vendor/k8s.io/client-go/util/flowcontrol/backoff.go b/metrics-server/vendor/k8s.io/client-go/util/flowcontrol/backoff.go
new file mode 100644
index 0000000..71d442a
--- /dev/null
+++ b/metrics-server/vendor/k8s.io/client-go/util/flowcontrol/backoff.go
@@ -0,0 +1,149 @@
+/*
+Copyright 2015 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 flowcontrol
+
+import (
+	"sync"
+	"time"
+
+	"k8s.io/apimachinery/pkg/util/clock"
+	"k8s.io/client-go/util/integer"
+)
+
+type backoffEntry struct {
+	backoff    time.Duration
+	lastUpdate time.Time
+}
+
+type Backoff struct {
+	sync.Mutex
+	Clock           clock.Clock
+	defaultDuration time.Duration
+	maxDuration     time.Duration
+	perItemBackoff  map[string]*backoffEntry
+}
+
+func NewFakeBackOff(initial, max time.Duration, tc *clock.FakeClock) *Backoff {
+	return &Backoff{
+		perItemBackoff:  map[string]*backoffEntry{},
+		Clock:           tc,
+		defaultDuration: initial,
+		maxDuration:     max,
+	}
+}
+
+func NewBackOff(initial, max time.Duration) *Backoff {
+	return &Backoff{
+		perItemBackoff:  map[string]*backoffEntry{},
+		Clock:           clock.RealClock{},
+		defaultDuration: initial,
+		maxDuration:     max,
+	}
+}
+
+// Get the current backoff Duration
+func (p *Backoff) Get(id string) time.Duration {
+	p.Lock()
+	defer p.Unlock()
+	var delay time.Duration
+	entry, ok := p.perItemBackoff[id]
+	if ok {
+		delay = entry.backoff
+	}
+	return delay
+}
+
+// move backoff to the next mark, capping at maxDuration
+func (p *Backoff) Next(id string, eventTime time.Time) {
+	p.Lock()
+	defer p.Unlock()
+	entry, ok := p.perItemBackoff[id]
+	if !ok || hasExpired(eventTime, entry.lastUpdate, p.maxDuration) {
+		entry = p.initEntryUnsafe(id)
+	} else {
+		delay := entry.backoff * 2 // exponential
+		entry.backoff = time.Duration(integer.Int64Min(int64(delay), int64(p.maxDuration)))
+	}
+	entry.lastUpdate = p.Clock.Now()
+}
+
+// Reset forces clearing of all backoff data for a given key.
+func (p *Backoff) Reset(id string) {
+	p.Lock()
+	defer p.Unlock()
+	delete(p.perItemBackoff, id)
+}
+
+// Returns True if the elapsed time since eventTime is smaller than the current backoff window
+func (p *Backoff) IsInBackOffSince(id string, eventTime time.Time) bool {
+	p.Lock()
+	defer p.Unlock()
+	entry, ok := p.perItemBackoff[id]
+	if !ok {
+		return false
+	}
+	if hasExpired(eventTime, entry.lastUpdate, p.maxDuration) {
+		return false
+	}
+	return p.Clock.Now().Sub(eventTime) < entry.backoff
+}
+
+// Returns True if time since lastupdate is less than the current backoff window.
+func (p *Backoff) IsInBackOffSinceUpdate(id string, eventTime time.Time) bool {
+	p.Lock()
+	defer p.Unlock()
+	entry, ok := p.perItemBackoff[id]
+	if !ok {
+		return false
+	}
+	if hasExpired(eventTime, entry.lastUpdate, p.maxDuration) {
+		return false
+	}
+	return eventTime.Sub(entry.lastUpdate) < entry.backoff
+}
+
+// Garbage collect records that have aged past maxDuration. Backoff users are expected
+// to invoke this periodically.
+func (p *Backoff) GC() {
+	p.Lock()
+	defer p.Unlock()
+	now := p.Clock.Now()
+	for id, entry := range p.perItemBackoff {
+		if now.Sub(entry.lastUpdate) > p.maxDuration*2 {
+			// GC when entry has not been updated for 2*maxDuration
+			delete(p.perItemBackoff, id)
+		}
+	}
+}
+
+func (p *Backoff) DeleteEntry(id string) {
+	p.Lock()
+	defer p.Unlock()
+	delete(p.perItemBackoff, id)
+}
+
+// Take a lock on *Backoff, before calling initEntryUnsafe
+func (p *Backoff) initEntryUnsafe(id string) *backoffEntry {
+	entry := &backoffEntry{backoff: p.defaultDuration}
+	p.perItemBackoff[id] = entry
+	return entry
+}
+
+// After 2*maxDuration we restart the backoff factor to the beginning
+func hasExpired(eventTime time.Time, lastUpdate time.Time, maxDuration time.Duration) bool {
+	return eventTime.Sub(lastUpdate) > maxDuration*2 // consider stable if it's ok for twice the maxDuration
+}
diff --git a/metrics-server/vendor/k8s.io/client-go/util/flowcontrol/throttle.go b/metrics-server/vendor/k8s.io/client-go/util/flowcontrol/throttle.go
new file mode 100644
index 0000000..e671c04
--- /dev/null
+++ b/metrics-server/vendor/k8s.io/client-go/util/flowcontrol/throttle.go
@@ -0,0 +1,143 @@
+/*
+Copyright 2014 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 flowcontrol
+
+import (
+	"sync"
+	"time"
+
+	"golang.org/x/time/rate"
+)
+
+type RateLimiter interface {
+	// TryAccept returns true if a token is taken immediately. Otherwise,
+	// it returns false.
+	TryAccept() bool
+	// Accept returns once a token becomes available.
+	Accept()
+	// Stop stops the rate limiter, subsequent calls to CanAccept will return false
+	Stop()
+	// QPS returns QPS of this rate limiter
+	QPS() float32
+}
+
+type tokenBucketRateLimiter struct {
+	limiter *rate.Limiter
+	clock   Clock
+	qps     float32
+}
+
+// NewTokenBucketRateLimiter creates a rate limiter which implements a token bucket approach.
+// The rate limiter allows bursts of up to 'burst' to exceed the QPS, while still maintaining a
+// smoothed qps rate of 'qps'.
+// The bucket is initially filled with 'burst' tokens, and refills at a rate of 'qps'.
+// The maximum number of tokens in the bucket is capped at 'burst'.
+func NewTokenBucketRateLimiter(qps float32, burst int) RateLimiter {
+	limiter := rate.NewLimiter(rate.Limit(qps), burst)
+	return newTokenBucketRateLimiter(limiter, realClock{}, qps)
+}
+
+// An injectable, mockable clock interface.
+type Clock interface {
+	Now() time.Time
+	Sleep(time.Duration)
+}
+
+type realClock struct{}
+
+func (realClock) Now() time.Time {
+	return time.Now()
+}
+func (realClock) Sleep(d time.Duration) {
+	time.Sleep(d)
+}
+
+// NewTokenBucketRateLimiterWithClock is identical to NewTokenBucketRateLimiter
+// but allows an injectable clock, for testing.
+func NewTokenBucketRateLimiterWithClock(qps float32, burst int, c Clock) RateLimiter {
+	limiter := rate.NewLimiter(rate.Limit(qps), burst)
+	return newTokenBucketRateLimiter(limiter, c, qps)
+}
+
+func newTokenBucketRateLimiter(limiter *rate.Limiter, c Clock, qps float32) RateLimiter {
+	return &tokenBucketRateLimiter{
+		limiter: limiter,
+		clock:   c,
+		qps:     qps,
+	}
+}
+
+func (t *tokenBucketRateLimiter) TryAccept() bool {
+	return t.limiter.AllowN(t.clock.Now(), 1)
+}
+
+// Accept will block until a token becomes available
+func (t *tokenBucketRateLimiter) Accept() {
+	now := t.clock.Now()
+	t.clock.Sleep(t.limiter.ReserveN(now, 1).DelayFrom(now))
+}
+
+func (t *tokenBucketRateLimiter) Stop() {
+}
+
+func (t *tokenBucketRateLimiter) QPS() float32 {
+	return t.qps
+}
+
+type fakeAlwaysRateLimiter struct{}
+
+func NewFakeAlwaysRateLimiter() RateLimiter {
+	return &fakeAlwaysRateLimiter{}
+}
+
+func (t *fakeAlwaysRateLimiter) TryAccept() bool {
+	return true
+}
+
+func (t *fakeAlwaysRateLimiter) Stop() {}
+
+func (t *fakeAlwaysRateLimiter) Accept() {}
+
+func (t *fakeAlwaysRateLimiter) QPS() float32 {
+	return 1
+}
+
+type fakeNeverRateLimiter struct {
+	wg sync.WaitGroup
+}
+
+func NewFakeNeverRateLimiter() RateLimiter {
+	rl := fakeNeverRateLimiter{}
+	rl.wg.Add(1)
+	return &rl
+}
+
+func (t *fakeNeverRateLimiter) TryAccept() bool {
+	return false
+}
+
+func (t *fakeNeverRateLimiter) Stop() {
+	t.wg.Done()
+}
+
+func (t *fakeNeverRateLimiter) Accept() {
+	t.wg.Wait()
+}
+
+func (t *fakeNeverRateLimiter) QPS() float32 {
+	return 1
+}
diff --git a/metrics-server/vendor/k8s.io/client-go/util/homedir/homedir.go b/metrics-server/vendor/k8s.io/client-go/util/homedir/homedir.go
new file mode 100644
index 0000000..816db57
--- /dev/null
+++ b/metrics-server/vendor/k8s.io/client-go/util/homedir/homedir.go
@@ -0,0 +1,47 @@
+/*
+Copyright 2016 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 homedir
+
+import (
+	"os"
+	"runtime"
+)
+
+// HomeDir returns the home directory for the current user
+func HomeDir() string {
+	if runtime.GOOS == "windows" {
+
+		// First prefer the HOME environmental variable
+		if home := os.Getenv("HOME"); len(home) > 0 {
+			if _, err := os.Stat(home); err == nil {
+				return home
+			}
+		}
+		if homeDrive, homePath := os.Getenv("HOMEDRIVE"), os.Getenv("HOMEPATH"); len(homeDrive) > 0 && len(homePath) > 0 {
+			homeDir := homeDrive + homePath
+			if _, err := os.Stat(homeDir); err == nil {
+				return homeDir
+			}
+		}
+		if userProfile := os.Getenv("USERPROFILE"); len(userProfile) > 0 {
+			if _, err := os.Stat(userProfile); err == nil {
+				return userProfile
+			}
+		}
+	}
+	return os.Getenv("HOME")
+}
diff --git a/metrics-server/vendor/k8s.io/client-go/util/integer/integer.go b/metrics-server/vendor/k8s.io/client-go/util/integer/integer.go
new file mode 100644
index 0000000..c6ea106
--- /dev/null
+++ b/metrics-server/vendor/k8s.io/client-go/util/integer/integer.go
@@ -0,0 +1,67 @@
+/*
+Copyright 2016 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 integer
+
+func IntMax(a, b int) int {
+	if b > a {
+		return b
+	}
+	return a
+}
+
+func IntMin(a, b int) int {
+	if b < a {
+		return b
+	}
+	return a
+}
+
+func Int32Max(a, b int32) int32 {
+	if b > a {
+		return b
+	}
+	return a
+}
+
+func Int32Min(a, b int32) int32 {
+	if b < a {
+		return b
+	}
+	return a
+}
+
+func Int64Max(a, b int64) int64 {
+	if b > a {
+		return b
+	}
+	return a
+}
+
+func Int64Min(a, b int64) int64 {
+	if b < a {
+		return b
+	}
+	return a
+}
+
+// RoundToInt32 rounds floats into integer numbers.
+func RoundToInt32(a float64) int32 {
+	if a < 0 {
+		return int32(a - 0.5)
+	}
+	return int32(a + 0.5)
+}
diff --git a/metrics-server/vendor/k8s.io/client-go/util/retry/OWNERS b/metrics-server/vendor/k8s.io/client-go/util/retry/OWNERS
new file mode 100755
index 0000000..a4c1c2d
--- /dev/null
+++ b/metrics-server/vendor/k8s.io/client-go/util/retry/OWNERS
@@ -0,0 +1,2 @@
+reviewers:
+- caesarxuchao
diff --git a/metrics-server/vendor/k8s.io/client-go/util/retry/util.go b/metrics-server/vendor/k8s.io/client-go/util/retry/util.go
new file mode 100644
index 0000000..3ac0840
--- /dev/null
+++ b/metrics-server/vendor/k8s.io/client-go/util/retry/util.go
@@ -0,0 +1,79 @@
+/*
+Copyright 2016 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 retry
+
+import (
+	"time"
+
+	"k8s.io/apimachinery/pkg/api/errors"
+	"k8s.io/apimachinery/pkg/util/wait"
+)
+
+// DefaultRetry is the recommended retry for a conflict where multiple clients
+// are making changes to the same resource.
+var DefaultRetry = wait.Backoff{
+	Steps:    5,
+	Duration: 10 * time.Millisecond,
+	Factor:   1.0,
+	Jitter:   0.1,
+}
+
+// DefaultBackoff is the recommended backoff for a conflict where a client
+// may be attempting to make an unrelated modification to a resource under
+// active management by one or more controllers.
+var DefaultBackoff = wait.Backoff{
+	Steps:    4,
+	Duration: 10 * time.Millisecond,
+	Factor:   5.0,
+	Jitter:   0.1,
+}
+
+// RetryConflict executes the provided function repeatedly, retrying if the server returns a conflicting
+// write. Callers should preserve previous executions if they wish to retry changes. It performs an
+// exponential backoff.
+//
+//     var pod *api.Pod
+//     err := RetryOnConflict(DefaultBackoff, func() (err error) {
+//       pod, err = c.Pods("mynamespace").UpdateStatus(podStatus)
+//       return
+//     })
+//     if err != nil {
+//       // may be conflict if max retries were hit
+//       return err
+//     }
+//     ...
+//
+// TODO: Make Backoff an interface?
+func RetryOnConflict(backoff wait.Backoff, fn func() error) error {
+	var lastConflictErr error
+	err := wait.ExponentialBackoff(backoff, func() (bool, error) {
+		err := fn()
+		switch {
+		case err == nil:
+			return true, nil
+		case errors.IsConflict(err):
+			lastConflictErr = err
+			return false, nil
+		default:
+			return false, err
+		}
+	})
+	if err == wait.ErrWaitTimeout {
+		err = lastConflictErr
+	}
+	return err
+}