vendor files

vendor/k8s.io/client-go/transport/round_trippers.go

@@ -0,0 +1,455 @@
+/*
+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 transport
+
+import (
+	"fmt"
+	"net/http"
+	"path/filepath"
+	"strings"
+	"time"
+
+	"github.com/golang/glog"
+	"github.com/gregjones/httpcache"
+	"github.com/gregjones/httpcache/diskcache"
+	"github.com/peterbourgon/diskv"
+
+	utilnet "k8s.io/apimachinery/pkg/util/net"
+)
+
+// HTTPWrappersForConfig wraps a round tripper with any relevant layered
+// behavior from the config. Exposed to allow more clients that need HTTP-like
+// behavior but then must hijack the underlying connection (like WebSocket or
+// HTTP2 clients). Pure HTTP clients should use the RoundTripper returned from
+// New.
+func HTTPWrappersForConfig(config *Config, rt http.RoundTripper) (http.RoundTripper, error) {
+	if config.WrapTransport != nil {
+		rt = config.WrapTransport(rt)
+	}
+
+	rt = DebugWrappers(rt)
+
+	// Set authentication wrappers
+	switch {
+	case config.HasBasicAuth() && config.HasTokenAuth():
+		return nil, fmt.Errorf("username/password or bearer token may be set, but not both")
+	case config.HasTokenAuth():
+		rt = NewBearerAuthRoundTripper(config.BearerToken, rt)
+	case config.HasBasicAuth():
+		rt = NewBasicAuthRoundTripper(config.Username, config.Password, rt)
+	}
+	if len(config.UserAgent) > 0 {
+		rt = NewUserAgentRoundTripper(config.UserAgent, rt)
+	}
+	if len(config.Impersonate.UserName) > 0 ||
+		len(config.Impersonate.Groups) > 0 ||
+		len(config.Impersonate.Extra) > 0 {
+		rt = NewImpersonatingRoundTripper(config.Impersonate, rt)
+	}
+	if len(config.CacheDir) > 0 {
+		rt = NewCacheRoundTripper(config.CacheDir, rt)
+	}
+	return rt, nil
+}
+
+// DebugWrappers wraps a round tripper and logs based on the current log level.
+func DebugWrappers(rt http.RoundTripper) http.RoundTripper {
+	switch {
+	case bool(glog.V(9)):
+		rt = newDebuggingRoundTripper(rt, debugCurlCommand, debugURLTiming, debugResponseHeaders)
+	case bool(glog.V(8)):
+		rt = newDebuggingRoundTripper(rt, debugJustURL, debugRequestHeaders, debugResponseStatus, debugResponseHeaders)
+	case bool(glog.V(7)):
+		rt = newDebuggingRoundTripper(rt, debugJustURL, debugRequestHeaders, debugResponseStatus)
+	case bool(glog.V(6)):
+		rt = newDebuggingRoundTripper(rt, debugURLTiming)
+	}
+
+	return rt
+}
+
+type requestCanceler interface {
+	CancelRequest(*http.Request)
+}
+
+type cacheRoundTripper struct {
+	rt *httpcache.Transport
+}
+
+// NewCacheRoundTripper creates a roundtripper that reads the ETag on
+// response headers and send the If-None-Match header on subsequent
+// corresponding requests.
+func NewCacheRoundTripper(cacheDir string, rt http.RoundTripper) http.RoundTripper {
+	d := diskv.New(diskv.Options{
+		BasePath: cacheDir,
+		TempDir:  filepath.Join(cacheDir, ".diskv-temp"),
+	})
+	t := httpcache.NewTransport(diskcache.NewWithDiskv(d))
+	t.Transport = rt
+
+	return &cacheRoundTripper{rt: t}
+}
+
+func (rt *cacheRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
+	return rt.rt.RoundTrip(req)
+}
+
+func (rt *cacheRoundTripper) WrappedRoundTripper() http.RoundTripper { return rt.rt.Transport }
+
+type authProxyRoundTripper struct {
+	username string
+	groups   []string
+	extra    map[string][]string
+
+	rt http.RoundTripper
+}
+
+// NewAuthProxyRoundTripper provides a roundtripper which will add auth proxy fields to requests for
+// authentication terminating proxy cases
+// assuming you pull the user from the context:
+// username is the user.Info.GetName() of the user
+// groups is the user.Info.GetGroups() of the user
+// extra is the user.Info.GetExtra() of the user
+// extra can contain any additional information that the authenticator
+// thought was interesting, for example authorization scopes.
+// In order to faithfully round-trip through an impersonation flow, these keys
+// MUST be lowercase.
+func NewAuthProxyRoundTripper(username string, groups []string, extra map[string][]string, rt http.RoundTripper) http.RoundTripper {
+	return &authProxyRoundTripper{
+		username: username,
+		groups:   groups,
+		extra:    extra,
+		rt:       rt,
+	}
+}
+
+func (rt *authProxyRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
+	req = utilnet.CloneRequest(req)
+	SetAuthProxyHeaders(req, rt.username, rt.groups, rt.extra)
+
+	return rt.rt.RoundTrip(req)
+}
+
+// SetAuthProxyHeaders stomps the auth proxy header fields.  It mutates its argument.
+func SetAuthProxyHeaders(req *http.Request, username string, groups []string, extra map[string][]string) {
+	req.Header.Del("X-Remote-User")
+	req.Header.Del("X-Remote-Group")
+	for key := range req.Header {
+		if strings.HasPrefix(strings.ToLower(key), strings.ToLower("X-Remote-Extra-")) {
+			req.Header.Del(key)
+		}
+	}
+
+	req.Header.Set("X-Remote-User", username)
+	for _, group := range groups {
+		req.Header.Add("X-Remote-Group", group)
+	}
+	for key, values := range extra {
+		for _, value := range values {
+			req.Header.Add("X-Remote-Extra-"+key, value)
+		}
+	}
+}
+
+func (rt *authProxyRoundTripper) CancelRequest(req *http.Request) {
+	if canceler, ok := rt.rt.(requestCanceler); ok {
+		canceler.CancelRequest(req)
+	} else {
+		glog.Errorf("CancelRequest not implemented")
+	}
+}
+
+func (rt *authProxyRoundTripper) WrappedRoundTripper() http.RoundTripper { return rt.rt }
+
+type userAgentRoundTripper struct {
+	agent string
+	rt    http.RoundTripper
+}
+
+func NewUserAgentRoundTripper(agent string, rt http.RoundTripper) http.RoundTripper {
+	return &userAgentRoundTripper{agent, rt}
+}
+
+func (rt *userAgentRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
+	if len(req.Header.Get("User-Agent")) != 0 {
+		return rt.rt.RoundTrip(req)
+	}
+	req = utilnet.CloneRequest(req)
+	req.Header.Set("User-Agent", rt.agent)
+	return rt.rt.RoundTrip(req)
+}
+
+func (rt *userAgentRoundTripper) CancelRequest(req *http.Request) {
+	if canceler, ok := rt.rt.(requestCanceler); ok {
+		canceler.CancelRequest(req)
+	} else {
+		glog.Errorf("CancelRequest not implemented")
+	}
+}
+
+func (rt *userAgentRoundTripper) WrappedRoundTripper() http.RoundTripper { return rt.rt }
+
+type basicAuthRoundTripper struct {
+	username string
+	password string
+	rt       http.RoundTripper
+}
+
+// NewBasicAuthRoundTripper will apply a BASIC auth authorization header to a
+// request unless it has already been set.
+func NewBasicAuthRoundTripper(username, password string, rt http.RoundTripper) http.RoundTripper {
+	return &basicAuthRoundTripper{username, password, rt}
+}
+
+func (rt *basicAuthRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
+	if len(req.Header.Get("Authorization")) != 0 {
+		return rt.rt.RoundTrip(req)
+	}
+	req = utilnet.CloneRequest(req)
+	req.SetBasicAuth(rt.username, rt.password)
+	return rt.rt.RoundTrip(req)
+}
+
+func (rt *basicAuthRoundTripper) CancelRequest(req *http.Request) {
+	if canceler, ok := rt.rt.(requestCanceler); ok {
+		canceler.CancelRequest(req)
+	} else {
+		glog.Errorf("CancelRequest not implemented")
+	}
+}
+
+func (rt *basicAuthRoundTripper) WrappedRoundTripper() http.RoundTripper { return rt.rt }
+
+// These correspond to the headers used in pkg/apis/authentication.  We don't want the package dependency,
+// but you must not change the values.
+const (
+	// ImpersonateUserHeader is used to impersonate a particular user during an API server request
+	ImpersonateUserHeader = "Impersonate-User"
+
+	// ImpersonateGroupHeader is used to impersonate a particular group during an API server request.
+	// It can be repeated multiplied times for multiple groups.
+	ImpersonateGroupHeader = "Impersonate-Group"
+
+	// ImpersonateUserExtraHeaderPrefix is a prefix for a header used to impersonate an entry in the
+	// extra map[string][]string for user.Info.  The key for the `extra` map is suffix.
+	// The same key can be repeated multiple times to have multiple elements in the slice under a single key.
+	// For instance:
+	// Impersonate-Extra-Foo: one
+	// Impersonate-Extra-Foo: two
+	// results in extra["Foo"] = []string{"one", "two"}
+	ImpersonateUserExtraHeaderPrefix = "Impersonate-Extra-"
+)
+
+type impersonatingRoundTripper struct {
+	impersonate ImpersonationConfig
+	delegate    http.RoundTripper
+}
+
+// NewImpersonatingRoundTripper will add an Act-As header to a request unless it has already been set.
+func NewImpersonatingRoundTripper(impersonate ImpersonationConfig, delegate http.RoundTripper) http.RoundTripper {
+	return &impersonatingRoundTripper{impersonate, delegate}
+}
+
+func (rt *impersonatingRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
+	// use the user header as marker for the rest.
+	if len(req.Header.Get(ImpersonateUserHeader)) != 0 {
+		return rt.delegate.RoundTrip(req)
+	}
+	req = utilnet.CloneRequest(req)
+	req.Header.Set(ImpersonateUserHeader, rt.impersonate.UserName)
+
+	for _, group := range rt.impersonate.Groups {
+		req.Header.Add(ImpersonateGroupHeader, group)
+	}
+	for k, vv := range rt.impersonate.Extra {
+		for _, v := range vv {
+			req.Header.Add(ImpersonateUserExtraHeaderPrefix+k, v)
+		}
+	}
+
+	return rt.delegate.RoundTrip(req)
+}
+
+func (rt *impersonatingRoundTripper) CancelRequest(req *http.Request) {
+	if canceler, ok := rt.delegate.(requestCanceler); ok {
+		canceler.CancelRequest(req)
+	} else {
+		glog.Errorf("CancelRequest not implemented")
+	}
+}
+
+func (rt *impersonatingRoundTripper) WrappedRoundTripper() http.RoundTripper { return rt.delegate }
+
+type bearerAuthRoundTripper struct {
+	bearer string
+	rt     http.RoundTripper
+}
+
+// NewBearerAuthRoundTripper adds the provided bearer token to a request
+// unless the authorization header has already been set.
+func NewBearerAuthRoundTripper(bearer string, rt http.RoundTripper) http.RoundTripper {
+	return &bearerAuthRoundTripper{bearer, rt}
+}
+
+func (rt *bearerAuthRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
+	if len(req.Header.Get("Authorization")) != 0 {
+		return rt.rt.RoundTrip(req)
+	}
+
+	req = utilnet.CloneRequest(req)
+	req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", rt.bearer))
+	return rt.rt.RoundTrip(req)
+}
+
+func (rt *bearerAuthRoundTripper) CancelRequest(req *http.Request) {
+	if canceler, ok := rt.rt.(requestCanceler); ok {
+		canceler.CancelRequest(req)
+	} else {
+		glog.Errorf("CancelRequest not implemented")
+	}
+}
+
+func (rt *bearerAuthRoundTripper) WrappedRoundTripper() http.RoundTripper { return rt.rt }
+
+// requestInfo keeps track of information about a request/response combination
+type requestInfo struct {
+	RequestHeaders http.Header
+	RequestVerb    string
+	RequestURL     string
+
+	ResponseStatus  string
+	ResponseHeaders http.Header
+	ResponseErr     error
+
+	Duration time.Duration
+}
+
+// newRequestInfo creates a new RequestInfo based on an http request
+func newRequestInfo(req *http.Request) *requestInfo {
+	return &requestInfo{
+		RequestURL:     req.URL.String(),
+		RequestVerb:    req.Method,
+		RequestHeaders: req.Header,
+	}
+}
+
+// complete adds information about the response to the requestInfo
+func (r *requestInfo) complete(response *http.Response, err error) {
+	if err != nil {
+		r.ResponseErr = err
+		return
+	}
+	r.ResponseStatus = response.Status
+	r.ResponseHeaders = response.Header
+}
+
+// toCurl returns a string that can be run as a command in a terminal (minus the body)
+func (r *requestInfo) toCurl() string {
+	headers := ""
+	for key, values := range r.RequestHeaders {
+		for _, value := range values {
+			headers += fmt.Sprintf(` -H %q`, fmt.Sprintf("%s: %s", key, value))
+		}
+	}
+
+	return fmt.Sprintf("curl -k -v -X%s %s %s", r.RequestVerb, headers, r.RequestURL)
+}
+
+// debuggingRoundTripper will display information about the requests passing
+// through it based on what is configured
+type debuggingRoundTripper struct {
+	delegatedRoundTripper http.RoundTripper
+
+	levels map[debugLevel]bool
+}
+
+type debugLevel int
+
+const (
+	debugJustURL debugLevel = iota
+	debugURLTiming
+	debugCurlCommand
+	debugRequestHeaders
+	debugResponseStatus
+	debugResponseHeaders
+)
+
+func newDebuggingRoundTripper(rt http.RoundTripper, levels ...debugLevel) *debuggingRoundTripper {
+	drt := &debuggingRoundTripper{
+		delegatedRoundTripper: rt,
+		levels:                make(map[debugLevel]bool, len(levels)),
+	}
+	for _, v := range levels {
+		drt.levels[v] = true
+	}
+	return drt
+}
+
+func (rt *debuggingRoundTripper) CancelRequest(req *http.Request) {
+	if canceler, ok := rt.delegatedRoundTripper.(requestCanceler); ok {
+		canceler.CancelRequest(req)
+	} else {
+		glog.Errorf("CancelRequest not implemented")
+	}
+}
+
+func (rt *debuggingRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
+	reqInfo := newRequestInfo(req)
+
+	if rt.levels[debugJustURL] {
+		glog.Infof("%s %s", reqInfo.RequestVerb, reqInfo.RequestURL)
+	}
+	if rt.levels[debugCurlCommand] {
+		glog.Infof("%s", reqInfo.toCurl())
+
+	}
+	if rt.levels[debugRequestHeaders] {
+		glog.Infof("Request Headers:")
+		for key, values := range reqInfo.RequestHeaders {
+			for _, value := range values {
+				glog.Infof("    %s: %s", key, value)
+			}
+		}
+	}
+
+	startTime := time.Now()
+	response, err := rt.delegatedRoundTripper.RoundTrip(req)
+	reqInfo.Duration = time.Since(startTime)
+
+	reqInfo.complete(response, err)
+
+	if rt.levels[debugURLTiming] {
+		glog.Infof("%s %s %s in %d milliseconds", reqInfo.RequestVerb, reqInfo.RequestURL, reqInfo.ResponseStatus, reqInfo.Duration.Nanoseconds()/int64(time.Millisecond))
+	}
+	if rt.levels[debugResponseStatus] {
+		glog.Infof("Response Status: %s in %d milliseconds", reqInfo.ResponseStatus, reqInfo.Duration.Nanoseconds()/int64(time.Millisecond))
+	}
+	if rt.levels[debugResponseHeaders] {
+		glog.Infof("Response Headers:")
+		for key, values := range reqInfo.ResponseHeaders {
+			for _, value := range values {
+				glog.Infof("    %s: %s", key, value)
+			}
+		}
+	}
+
+	return response, err
+}
+
+func (rt *debuggingRoundTripper) WrappedRoundTripper() http.RoundTripper {
+	return rt.delegatedRoundTripper
+}