diff --git a/metrics-server/vendor/k8s.io/apimachinery/pkg/util/net/http.go b/metrics-server/vendor/k8s.io/apimachinery/pkg/util/net/http.go
new file mode 100644
index 0000000..7ea2df2
--- /dev/null
+++ b/metrics-server/vendor/k8s.io/apimachinery/pkg/util/net/http.go
@@ -0,0 +1,426 @@
+/*
+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 net
+
+import (
+	"bufio"
+	"bytes"
+	"context"
+	"crypto/tls"
+	"fmt"
+	"io"
+	"net"
+	"net/http"
+	"net/url"
+	"os"
+	"path"
+	"strconv"
+	"strings"
+
+	"github.com/golang/glog"
+	"golang.org/x/net/http2"
+)
+
+// JoinPreservingTrailingSlash does a path.Join of the specified elements,
+// preserving any trailing slash on the last non-empty segment
+func JoinPreservingTrailingSlash(elem ...string) string {
+	// do the basic path join
+	result := path.Join(elem...)
+
+	// find the last non-empty segment
+	for i := len(elem) - 1; i >= 0; i-- {
+		if len(elem[i]) > 0 {
+			// if the last segment ended in a slash, ensure our result does as well
+			if strings.HasSuffix(elem[i], "/") && !strings.HasSuffix(result, "/") {
+				result += "/"
+			}
+			break
+		}
+	}
+
+	return result
+}
+
+// IsProbableEOF returns true if the given error resembles a connection termination
+// scenario that would justify assuming that the watch is empty.
+// These errors are what the Go http stack returns back to us which are general
+// connection closure errors (strongly correlated) and callers that need to
+// differentiate probable errors in connection behavior between normal "this is
+// disconnected" should use the method.
+func IsProbableEOF(err error) bool {
+	if err == nil {
+		return false
+	}
+	if uerr, ok := err.(*url.Error); ok {
+		err = uerr.Err
+	}
+	switch {
+	case err == io.EOF:
+		return true
+	case err.Error() == "http: can't write HTTP request on broken connection":
+		return true
+	case strings.Contains(err.Error(), "connection reset by peer"):
+		return true
+	case strings.Contains(strings.ToLower(err.Error()), "use of closed network connection"):
+		return true
+	}
+	return false
+}
+
+var defaultTransport = http.DefaultTransport.(*http.Transport)
+
+// SetOldTransportDefaults applies the defaults from http.DefaultTransport
+// for the Proxy, Dial, and TLSHandshakeTimeout fields if unset
+func SetOldTransportDefaults(t *http.Transport) *http.Transport {
+	if t.Proxy == nil || isDefault(t.Proxy) {
+		// http.ProxyFromEnvironment doesn't respect CIDRs and that makes it impossible to exclude things like pod and service IPs from proxy settings
+		// ProxierWithNoProxyCIDR allows CIDR rules in NO_PROXY
+		t.Proxy = NewProxierWithNoProxyCIDR(http.ProxyFromEnvironment)
+	}
+	if t.DialContext == nil {
+		t.DialContext = defaultTransport.DialContext
+	}
+	if t.TLSHandshakeTimeout == 0 {
+		t.TLSHandshakeTimeout = defaultTransport.TLSHandshakeTimeout
+	}
+	return t
+}
+
+// SetTransportDefaults applies the defaults from http.DefaultTransport
+// for the Proxy, Dial, and TLSHandshakeTimeout fields if unset
+func SetTransportDefaults(t *http.Transport) *http.Transport {
+	t = SetOldTransportDefaults(t)
+	// Allow clients to disable http2 if needed.
+	if s := os.Getenv("DISABLE_HTTP2"); len(s) > 0 {
+		glog.Infof("HTTP2 has been explicitly disabled")
+	} else {
+		if err := http2.ConfigureTransport(t); err != nil {
+			glog.Warningf("Transport failed http2 configuration: %v", err)
+		}
+	}
+	return t
+}
+
+type RoundTripperWrapper interface {
+	http.RoundTripper
+	WrappedRoundTripper() http.RoundTripper
+}
+
+type DialFunc func(ctx context.Context, net, addr string) (net.Conn, error)
+
+func DialerFor(transport http.RoundTripper) (DialFunc, error) {
+	if transport == nil {
+		return nil, nil
+	}
+
+	switch transport := transport.(type) {
+	case *http.Transport:
+		return transport.DialContext, nil
+	case RoundTripperWrapper:
+		return DialerFor(transport.WrappedRoundTripper())
+	default:
+		return nil, fmt.Errorf("unknown transport type: %T", transport)
+	}
+}
+
+type TLSClientConfigHolder interface {
+	TLSClientConfig() *tls.Config
+}
+
+func TLSClientConfig(transport http.RoundTripper) (*tls.Config, error) {
+	if transport == nil {
+		return nil, nil
+	}
+
+	switch transport := transport.(type) {
+	case *http.Transport:
+		return transport.TLSClientConfig, nil
+	case TLSClientConfigHolder:
+		return transport.TLSClientConfig(), nil
+	case RoundTripperWrapper:
+		return TLSClientConfig(transport.WrappedRoundTripper())
+	default:
+		return nil, fmt.Errorf("unknown transport type: %T", transport)
+	}
+}
+
+func FormatURL(scheme string, host string, port int, path string) *url.URL {
+	return &url.URL{
+		Scheme: scheme,
+		Host:   net.JoinHostPort(host, strconv.Itoa(port)),
+		Path:   path,
+	}
+}
+
+func GetHTTPClient(req *http.Request) string {
+	if userAgent, ok := req.Header["User-Agent"]; ok {
+		if len(userAgent) > 0 {
+			return userAgent[0]
+		}
+	}
+	return "unknown"
+}
+
+// SourceIPs splits the comma separated X-Forwarded-For header or returns the X-Real-Ip header or req.RemoteAddr,
+// in that order, ignoring invalid IPs. It returns nil if all of these are empty or invalid.
+func SourceIPs(req *http.Request) []net.IP {
+	hdr := req.Header
+	// First check the X-Forwarded-For header for requests via proxy.
+	hdrForwardedFor := hdr.Get("X-Forwarded-For")
+	forwardedForIPs := []net.IP{}
+	if hdrForwardedFor != "" {
+		// X-Forwarded-For can be a csv of IPs in case of multiple proxies.
+		// Use the first valid one.
+		parts := strings.Split(hdrForwardedFor, ",")
+		for _, part := range parts {
+			ip := net.ParseIP(strings.TrimSpace(part))
+			if ip != nil {
+				forwardedForIPs = append(forwardedForIPs, ip)
+			}
+		}
+	}
+	if len(forwardedForIPs) > 0 {
+		return forwardedForIPs
+	}
+
+	// Try the X-Real-Ip header.
+	hdrRealIp := hdr.Get("X-Real-Ip")
+	if hdrRealIp != "" {
+		ip := net.ParseIP(hdrRealIp)
+		if ip != nil {
+			return []net.IP{ip}
+		}
+	}
+
+	// Fallback to Remote Address in request, which will give the correct client IP when there is no proxy.
+	// Remote Address in Go's HTTP server is in the form host:port so we need to split that first.
+	host, _, err := net.SplitHostPort(req.RemoteAddr)
+	if err == nil {
+		if remoteIP := net.ParseIP(host); remoteIP != nil {
+			return []net.IP{remoteIP}
+		}
+	}
+
+	// Fallback if Remote Address was just IP.
+	if remoteIP := net.ParseIP(req.RemoteAddr); remoteIP != nil {
+		return []net.IP{remoteIP}
+	}
+
+	return nil
+}
+
+// Extracts and returns the clients IP from the given request.
+// Looks at X-Forwarded-For header, X-Real-Ip header and request.RemoteAddr in that order.
+// Returns nil if none of them are set or is set to an invalid value.
+func GetClientIP(req *http.Request) net.IP {
+	ips := SourceIPs(req)
+	if len(ips) == 0 {
+		return nil
+	}
+	return ips[0]
+}
+
+// Prepares the X-Forwarded-For header for another forwarding hop by appending the previous sender's
+// IP address to the X-Forwarded-For chain.
+func AppendForwardedForHeader(req *http.Request) {
+	// Copied from net/http/httputil/reverseproxy.go:
+	if clientIP, _, err := net.SplitHostPort(req.RemoteAddr); err == nil {
+		// If we aren't the first proxy retain prior
+		// X-Forwarded-For information as a comma+space
+		// separated list and fold multiple headers into one.
+		if prior, ok := req.Header["X-Forwarded-For"]; ok {
+			clientIP = strings.Join(prior, ", ") + ", " + clientIP
+		}
+		req.Header.Set("X-Forwarded-For", clientIP)
+	}
+}
+
+var defaultProxyFuncPointer = fmt.Sprintf("%p", http.ProxyFromEnvironment)
+
+// isDefault checks to see if the transportProxierFunc is pointing to the default one
+func isDefault(transportProxier func(*http.Request) (*url.URL, error)) bool {
+	transportProxierPointer := fmt.Sprintf("%p", transportProxier)
+	return transportProxierPointer == defaultProxyFuncPointer
+}
+
+// NewProxierWithNoProxyCIDR constructs a Proxier function that respects CIDRs in NO_PROXY and delegates if
+// no matching CIDRs are found
+func NewProxierWithNoProxyCIDR(delegate func(req *http.Request) (*url.URL, error)) func(req *http.Request) (*url.URL, error) {
+	// we wrap the default method, so we only need to perform our check if the NO_PROXY (or no_proxy) envvar has a CIDR in it
+	noProxyEnv := os.Getenv("NO_PROXY")
+	if noProxyEnv == "" {
+		noProxyEnv = os.Getenv("no_proxy")
+	}
+	noProxyRules := strings.Split(noProxyEnv, ",")
+
+	cidrs := []*net.IPNet{}
+	for _, noProxyRule := range noProxyRules {
+		_, cidr, _ := net.ParseCIDR(noProxyRule)
+		if cidr != nil {
+			cidrs = append(cidrs, cidr)
+		}
+	}
+
+	if len(cidrs) == 0 {
+		return delegate
+	}
+
+	return func(req *http.Request) (*url.URL, error) {
+		ip := net.ParseIP(req.URL.Hostname())
+		if ip == nil {
+			return delegate(req)
+		}
+
+		for _, cidr := range cidrs {
+			if cidr.Contains(ip) {
+				return nil, nil
+			}
+		}
+
+		return delegate(req)
+	}
+}
+
+// DialerFunc implements Dialer for the provided function.
+type DialerFunc func(req *http.Request) (net.Conn, error)
+
+func (fn DialerFunc) Dial(req *http.Request) (net.Conn, error) {
+	return fn(req)
+}
+
+// Dialer dials a host and writes a request to it.
+type Dialer interface {
+	// Dial connects to the host specified by req's URL, writes the request to the connection, and
+	// returns the opened net.Conn.
+	Dial(req *http.Request) (net.Conn, error)
+}
+
+// ConnectWithRedirects uses dialer to send req, following up to 10 redirects (relative to
+// originalLocation). It returns the opened net.Conn and the raw response bytes.
+func ConnectWithRedirects(originalMethod string, originalLocation *url.URL, header http.Header, originalBody io.Reader, dialer Dialer) (net.Conn, []byte, error) {
+	const (
+		maxRedirects    = 10
+		maxResponseSize = 16384 // play it safe to allow the potential for lots of / large headers
+	)
+
+	var (
+		location         = originalLocation
+		method           = originalMethod
+		intermediateConn net.Conn
+		rawResponse      = bytes.NewBuffer(make([]byte, 0, 256))
+		body             = originalBody
+	)
+
+	defer func() {
+		if intermediateConn != nil {
+			intermediateConn.Close()
+		}
+	}()
+
+redirectLoop:
+	for redirects := 0; ; redirects++ {
+		if redirects > maxRedirects {
+			return nil, nil, fmt.Errorf("too many redirects (%d)", redirects)
+		}
+
+		req, err := http.NewRequest(method, location.String(), body)
+		if err != nil {
+			return nil, nil, err
+		}
+
+		req.Header = header
+
+		intermediateConn, err = dialer.Dial(req)
+		if err != nil {
+			return nil, nil, err
+		}
+
+		// Peek at the backend response.
+		rawResponse.Reset()
+		respReader := bufio.NewReader(io.TeeReader(
+			io.LimitReader(intermediateConn, maxResponseSize), // Don't read more than maxResponseSize bytes.
+			rawResponse)) // Save the raw response.
+		resp, err := http.ReadResponse(respReader, nil)
+		if err != nil {
+			// Unable to read the backend response; let the client handle it.
+			glog.Warningf("Error reading backend response: %v", err)
+			break redirectLoop
+		}
+
+		switch resp.StatusCode {
+		case http.StatusFound:
+			// Redirect, continue.
+		default:
+			// Don't redirect.
+			break redirectLoop
+		}
+
+		// Redirected requests switch to "GET" according to the HTTP spec:
+		// https://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.3
+		method = "GET"
+		// don't send a body when following redirects
+		body = nil
+
+		resp.Body.Close() // not used
+
+		// Reset the connection.
+		intermediateConn.Close()
+		intermediateConn = nil
+
+		// Prepare to follow the redirect.
+		redirectStr := resp.Header.Get("Location")
+		if redirectStr == "" {
+			return nil, nil, fmt.Errorf("%d response missing Location header", resp.StatusCode)
+		}
+		// We have to parse relative to the current location, NOT originalLocation. For example,
+		// if we request http://foo.com/a and get back "http://bar.com/b", the result should be
+		// http://bar.com/b. If we then make that request and get back a redirect to "/c", the result
+		// should be http://bar.com/c, not http://foo.com/c.
+		location, err = location.Parse(redirectStr)
+		if err != nil {
+			return nil, nil, fmt.Errorf("malformed Location header: %v", err)
+		}
+	}
+
+	connToReturn := intermediateConn
+	intermediateConn = nil // Don't close the connection when we return it.
+	return connToReturn, rawResponse.Bytes(), nil
+}
+
+// CloneRequest creates a shallow copy of the request along with a deep copy of the Headers.
+func CloneRequest(req *http.Request) *http.Request {
+	r := new(http.Request)
+
+	// shallow clone
+	*r = *req
+
+	// deep copy headers
+	r.Header = CloneHeader(req.Header)
+
+	return r
+}
+
+// CloneHeader creates a deep copy of an http.Header.
+func CloneHeader(in http.Header) http.Header {
+	out := make(http.Header, len(in))
+	for key, values := range in {
+		newValues := make([]string, len(values))
+		copy(newValues, values)
+		out[key] = newValues
+	}
+	return out
+}