Import of https://github.com/ciena/voltctl at commit 40d61fbf3f910ed4017cf67c9c79e8e1f82a33a5
Change-Id: I8464c59e60d76cb8612891db3303878975b5416c
diff --git a/vendor/k8s.io/client-go/rest/request.go b/vendor/k8s.io/client-go/rest/request.go
new file mode 100644
index 0000000..dd06303
--- /dev/null
+++ b/vendor/k8s.io/client-go/rest/request.go
@@ -0,0 +1,1201 @@
+/*
+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 rest
+
+import (
+ "bytes"
+ "context"
+ "encoding/hex"
+ "fmt"
+ "io"
+ "io/ioutil"
+ "mime"
+ "net/http"
+ "net/url"
+ "path"
+ "reflect"
+ "strconv"
+ "strings"
+ "time"
+
+ "golang.org/x/net/http2"
+ "k8s.io/apimachinery/pkg/api/errors"
+ metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+ "k8s.io/apimachinery/pkg/runtime"
+ "k8s.io/apimachinery/pkg/runtime/schema"
+ "k8s.io/apimachinery/pkg/runtime/serializer/streaming"
+ "k8s.io/apimachinery/pkg/util/net"
+ "k8s.io/apimachinery/pkg/watch"
+ restclientwatch "k8s.io/client-go/rest/watch"
+ "k8s.io/client-go/tools/metrics"
+ "k8s.io/client-go/util/flowcontrol"
+ "k8s.io/klog"
+)
+
+var (
+ // longThrottleLatency defines threshold for logging requests. All requests being
+ // throttle for more than longThrottleLatency will be logged.
+ longThrottleLatency = 50 * time.Millisecond
+)
+
+// HTTPClient is an interface for testing a request object.
+type HTTPClient interface {
+ Do(req *http.Request) (*http.Response, error)
+}
+
+// ResponseWrapper is an interface for getting a response.
+// The response may be either accessed as a raw data (the whole output is put into memory) or as a stream.
+type ResponseWrapper interface {
+ DoRaw() ([]byte, error)
+ Stream() (io.ReadCloser, error)
+}
+
+// RequestConstructionError is returned when there's an error assembling a request.
+type RequestConstructionError struct {
+ Err error
+}
+
+// Error returns a textual description of 'r'.
+func (r *RequestConstructionError) Error() string {
+ return fmt.Sprintf("request construction error: '%v'", r.Err)
+}
+
+// Request allows for building up a request to a server in a chained fashion.
+// Any errors are stored until the end of your call, so you only have to
+// check once.
+type Request struct {
+ // required
+ client HTTPClient
+ verb string
+
+ baseURL *url.URL
+ content ContentConfig
+ serializers Serializers
+
+ // generic components accessible via method setters
+ pathPrefix string
+ subpath string
+ params url.Values
+ headers http.Header
+
+ // structural elements of the request that are part of the Kubernetes API conventions
+ namespace string
+ namespaceSet bool
+ resource string
+ resourceName string
+ subresource string
+ timeout time.Duration
+
+ // output
+ err error
+ body io.Reader
+
+ // This is only used for per-request timeouts, deadlines, and cancellations.
+ ctx context.Context
+
+ backoffMgr BackoffManager
+ throttle flowcontrol.RateLimiter
+}
+
+// NewRequest creates a new request helper object for accessing runtime.Objects on a server.
+func NewRequest(client HTTPClient, verb string, baseURL *url.URL, versionedAPIPath string, content ContentConfig, serializers Serializers, backoff BackoffManager, throttle flowcontrol.RateLimiter, timeout time.Duration) *Request {
+ if backoff == nil {
+ klog.V(2).Infof("Not implementing request backoff strategy.")
+ backoff = &NoBackoff{}
+ }
+
+ pathPrefix := "/"
+ if baseURL != nil {
+ pathPrefix = path.Join(pathPrefix, baseURL.Path)
+ }
+ r := &Request{
+ client: client,
+ verb: verb,
+ baseURL: baseURL,
+ pathPrefix: path.Join(pathPrefix, versionedAPIPath),
+ content: content,
+ serializers: serializers,
+ backoffMgr: backoff,
+ throttle: throttle,
+ timeout: timeout,
+ }
+ switch {
+ case len(content.AcceptContentTypes) > 0:
+ r.SetHeader("Accept", content.AcceptContentTypes)
+ case len(content.ContentType) > 0:
+ r.SetHeader("Accept", content.ContentType+", */*")
+ }
+ return r
+}
+
+// Prefix adds segments to the relative beginning to the request path. These
+// items will be placed before the optional Namespace, Resource, or Name sections.
+// Setting AbsPath will clear any previously set Prefix segments
+func (r *Request) Prefix(segments ...string) *Request {
+ if r.err != nil {
+ return r
+ }
+ r.pathPrefix = path.Join(r.pathPrefix, path.Join(segments...))
+ return r
+}
+
+// Suffix appends segments to the end of the path. These items will be placed after the prefix and optional
+// Namespace, Resource, or Name sections.
+func (r *Request) Suffix(segments ...string) *Request {
+ if r.err != nil {
+ return r
+ }
+ r.subpath = path.Join(r.subpath, path.Join(segments...))
+ return r
+}
+
+// Resource sets the resource to access (<resource>/[ns/<namespace>/]<name>)
+func (r *Request) Resource(resource string) *Request {
+ if r.err != nil {
+ return r
+ }
+ if len(r.resource) != 0 {
+ r.err = fmt.Errorf("resource already set to %q, cannot change to %q", r.resource, resource)
+ return r
+ }
+ if msgs := IsValidPathSegmentName(resource); len(msgs) != 0 {
+ r.err = fmt.Errorf("invalid resource %q: %v", resource, msgs)
+ return r
+ }
+ r.resource = resource
+ return r
+}
+
+// BackOff sets the request's backoff manager to the one specified,
+// or defaults to the stub implementation if nil is provided
+func (r *Request) BackOff(manager BackoffManager) *Request {
+ if manager == nil {
+ r.backoffMgr = &NoBackoff{}
+ return r
+ }
+
+ r.backoffMgr = manager
+ return r
+}
+
+// Throttle receives a rate-limiter and sets or replaces an existing request limiter
+func (r *Request) Throttle(limiter flowcontrol.RateLimiter) *Request {
+ r.throttle = limiter
+ return r
+}
+
+// SubResource sets a sub-resource path which can be multiple segments after the resource
+// name but before the suffix.
+func (r *Request) SubResource(subresources ...string) *Request {
+ if r.err != nil {
+ return r
+ }
+ subresource := path.Join(subresources...)
+ if len(r.subresource) != 0 {
+ r.err = fmt.Errorf("subresource already set to %q, cannot change to %q", r.resource, subresource)
+ return r
+ }
+ for _, s := range subresources {
+ if msgs := IsValidPathSegmentName(s); len(msgs) != 0 {
+ r.err = fmt.Errorf("invalid subresource %q: %v", s, msgs)
+ return r
+ }
+ }
+ r.subresource = subresource
+ return r
+}
+
+// Name sets the name of a resource to access (<resource>/[ns/<namespace>/]<name>)
+func (r *Request) Name(resourceName string) *Request {
+ if r.err != nil {
+ return r
+ }
+ if len(resourceName) == 0 {
+ r.err = fmt.Errorf("resource name may not be empty")
+ return r
+ }
+ if len(r.resourceName) != 0 {
+ r.err = fmt.Errorf("resource name already set to %q, cannot change to %q", r.resourceName, resourceName)
+ return r
+ }
+ if msgs := IsValidPathSegmentName(resourceName); len(msgs) != 0 {
+ r.err = fmt.Errorf("invalid resource name %q: %v", resourceName, msgs)
+ return r
+ }
+ r.resourceName = resourceName
+ return r
+}
+
+// Namespace applies the namespace scope to a request (<resource>/[ns/<namespace>/]<name>)
+func (r *Request) Namespace(namespace string) *Request {
+ if r.err != nil {
+ return r
+ }
+ if r.namespaceSet {
+ r.err = fmt.Errorf("namespace already set to %q, cannot change to %q", r.namespace, namespace)
+ return r
+ }
+ if msgs := IsValidPathSegmentName(namespace); len(msgs) != 0 {
+ r.err = fmt.Errorf("invalid namespace %q: %v", namespace, msgs)
+ return r
+ }
+ r.namespaceSet = true
+ r.namespace = namespace
+ return r
+}
+
+// NamespaceIfScoped is a convenience function to set a namespace if scoped is true
+func (r *Request) NamespaceIfScoped(namespace string, scoped bool) *Request {
+ if scoped {
+ return r.Namespace(namespace)
+ }
+ return r
+}
+
+// AbsPath overwrites an existing path with the segments provided. Trailing slashes are preserved
+// when a single segment is passed.
+func (r *Request) AbsPath(segments ...string) *Request {
+ if r.err != nil {
+ return r
+ }
+ r.pathPrefix = path.Join(r.baseURL.Path, path.Join(segments...))
+ if len(segments) == 1 && (len(r.baseURL.Path) > 1 || len(segments[0]) > 1) && strings.HasSuffix(segments[0], "/") {
+ // preserve any trailing slashes for legacy behavior
+ r.pathPrefix += "/"
+ }
+ return r
+}
+
+// RequestURI overwrites existing path and parameters with the value of the provided server relative
+// URI.
+func (r *Request) RequestURI(uri string) *Request {
+ if r.err != nil {
+ return r
+ }
+ locator, err := url.Parse(uri)
+ if err != nil {
+ r.err = err
+ return r
+ }
+ r.pathPrefix = locator.Path
+ if len(locator.Query()) > 0 {
+ if r.params == nil {
+ r.params = make(url.Values)
+ }
+ for k, v := range locator.Query() {
+ r.params[k] = v
+ }
+ }
+ return r
+}
+
+// Param creates a query parameter with the given string value.
+func (r *Request) Param(paramName, s string) *Request {
+ if r.err != nil {
+ return r
+ }
+ return r.setParam(paramName, s)
+}
+
+// VersionedParams will take the provided object, serialize it to a map[string][]string using the
+// implicit RESTClient API version and the default parameter codec, and then add those as parameters
+// to the request. Use this to provide versioned query parameters from client libraries.
+// VersionedParams will not write query parameters that have omitempty set and are empty. If a
+// parameter has already been set it is appended to (Params and VersionedParams are additive).
+func (r *Request) VersionedParams(obj runtime.Object, codec runtime.ParameterCodec) *Request {
+ return r.SpecificallyVersionedParams(obj, codec, *r.content.GroupVersion)
+}
+
+func (r *Request) SpecificallyVersionedParams(obj runtime.Object, codec runtime.ParameterCodec, version schema.GroupVersion) *Request {
+ if r.err != nil {
+ return r
+ }
+ params, err := codec.EncodeParameters(obj, version)
+ if err != nil {
+ r.err = err
+ return r
+ }
+ for k, v := range params {
+ if r.params == nil {
+ r.params = make(url.Values)
+ }
+ r.params[k] = append(r.params[k], v...)
+ }
+ return r
+}
+
+func (r *Request) setParam(paramName, value string) *Request {
+ if r.params == nil {
+ r.params = make(url.Values)
+ }
+ r.params[paramName] = append(r.params[paramName], value)
+ return r
+}
+
+func (r *Request) SetHeader(key string, values ...string) *Request {
+ if r.headers == nil {
+ r.headers = http.Header{}
+ }
+ r.headers.Del(key)
+ for _, value := range values {
+ r.headers.Add(key, value)
+ }
+ return r
+}
+
+// Timeout makes the request use the given duration as an overall timeout for the
+// request. Additionally, if set passes the value as "timeout" parameter in URL.
+func (r *Request) Timeout(d time.Duration) *Request {
+ if r.err != nil {
+ return r
+ }
+ r.timeout = d
+ return r
+}
+
+// Body makes the request use obj as the body. Optional.
+// If obj is a string, try to read a file of that name.
+// If obj is a []byte, send it directly.
+// If obj is an io.Reader, use it directly.
+// If obj is a runtime.Object, marshal it correctly, and set Content-Type header.
+// If obj is a runtime.Object and nil, do nothing.
+// Otherwise, set an error.
+func (r *Request) Body(obj interface{}) *Request {
+ if r.err != nil {
+ return r
+ }
+ switch t := obj.(type) {
+ case string:
+ data, err := ioutil.ReadFile(t)
+ if err != nil {
+ r.err = err
+ return r
+ }
+ glogBody("Request Body", data)
+ r.body = bytes.NewReader(data)
+ case []byte:
+ glogBody("Request Body", t)
+ r.body = bytes.NewReader(t)
+ case io.Reader:
+ r.body = t
+ case runtime.Object:
+ // callers may pass typed interface pointers, therefore we must check nil with reflection
+ if reflect.ValueOf(t).IsNil() {
+ return r
+ }
+ data, err := runtime.Encode(r.serializers.Encoder, t)
+ if err != nil {
+ r.err = err
+ return r
+ }
+ glogBody("Request Body", data)
+ r.body = bytes.NewReader(data)
+ r.SetHeader("Content-Type", r.content.ContentType)
+ default:
+ r.err = fmt.Errorf("unknown type used for body: %+v", obj)
+ }
+ return r
+}
+
+// Context adds a context to the request. Contexts are only used for
+// timeouts, deadlines, and cancellations.
+func (r *Request) Context(ctx context.Context) *Request {
+ r.ctx = ctx
+ return r
+}
+
+// URL returns the current working URL.
+func (r *Request) URL() *url.URL {
+ p := r.pathPrefix
+ if r.namespaceSet && len(r.namespace) > 0 {
+ p = path.Join(p, "namespaces", r.namespace)
+ }
+ if len(r.resource) != 0 {
+ p = path.Join(p, strings.ToLower(r.resource))
+ }
+ // Join trims trailing slashes, so preserve r.pathPrefix's trailing slash for backwards compatibility if nothing was changed
+ if len(r.resourceName) != 0 || len(r.subpath) != 0 || len(r.subresource) != 0 {
+ p = path.Join(p, r.resourceName, r.subresource, r.subpath)
+ }
+
+ finalURL := &url.URL{}
+ if r.baseURL != nil {
+ *finalURL = *r.baseURL
+ }
+ finalURL.Path = p
+
+ query := url.Values{}
+ for key, values := range r.params {
+ for _, value := range values {
+ query.Add(key, value)
+ }
+ }
+
+ // timeout is handled specially here.
+ if r.timeout != 0 {
+ query.Set("timeout", r.timeout.String())
+ }
+ finalURL.RawQuery = query.Encode()
+ return finalURL
+}
+
+// finalURLTemplate is similar to URL(), but will make all specific parameter values equal
+// - instead of name or namespace, "{name}" and "{namespace}" will be used, and all query
+// parameters will be reset. This creates a copy of the url so as not to change the
+// underlying object.
+func (r Request) finalURLTemplate() url.URL {
+ newParams := url.Values{}
+ v := []string{"{value}"}
+ for k := range r.params {
+ newParams[k] = v
+ }
+ r.params = newParams
+ url := r.URL()
+ segments := strings.Split(r.URL().Path, "/")
+ groupIndex := 0
+ index := 0
+ if r.URL() != nil && r.baseURL != nil && strings.Contains(r.URL().Path, r.baseURL.Path) {
+ groupIndex += len(strings.Split(r.baseURL.Path, "/"))
+ }
+ if groupIndex >= len(segments) {
+ return *url
+ }
+
+ const CoreGroupPrefix = "api"
+ const NamedGroupPrefix = "apis"
+ isCoreGroup := segments[groupIndex] == CoreGroupPrefix
+ isNamedGroup := segments[groupIndex] == NamedGroupPrefix
+ if isCoreGroup {
+ // checking the case of core group with /api/v1/... format
+ index = groupIndex + 2
+ } else if isNamedGroup {
+ // checking the case of named group with /apis/apps/v1/... format
+ index = groupIndex + 3
+ } else {
+ // this should not happen that the only two possibilities are /api... and /apis..., just want to put an
+ // outlet here in case more API groups are added in future if ever possible:
+ // https://kubernetes.io/docs/concepts/overview/kubernetes-api/#api-groups
+ // if a wrong API groups name is encountered, return the {prefix} for url.Path
+ url.Path = "/{prefix}"
+ url.RawQuery = ""
+ return *url
+ }
+ //switch segLength := len(segments) - index; segLength {
+ switch {
+ // case len(segments) - index == 1:
+ // resource (with no name) do nothing
+ case len(segments)-index == 2:
+ // /$RESOURCE/$NAME: replace $NAME with {name}
+ segments[index+1] = "{name}"
+ case len(segments)-index == 3:
+ if segments[index+2] == "finalize" || segments[index+2] == "status" {
+ // /$RESOURCE/$NAME/$SUBRESOURCE: replace $NAME with {name}
+ segments[index+1] = "{name}"
+ } else {
+ // /namespace/$NAMESPACE/$RESOURCE: replace $NAMESPACE with {namespace}
+ segments[index+1] = "{namespace}"
+ }
+ case len(segments)-index >= 4:
+ segments[index+1] = "{namespace}"
+ // /namespace/$NAMESPACE/$RESOURCE/$NAME: replace $NAMESPACE with {namespace}, $NAME with {name}
+ if segments[index+3] != "finalize" && segments[index+3] != "status" {
+ // /$RESOURCE/$NAME/$SUBRESOURCE: replace $NAME with {name}
+ segments[index+3] = "{name}"
+ }
+ }
+ url.Path = path.Join(segments...)
+ return *url
+}
+
+func (r *Request) tryThrottle() {
+ now := time.Now()
+ if r.throttle != nil {
+ r.throttle.Accept()
+ }
+ if latency := time.Since(now); latency > longThrottleLatency {
+ klog.V(4).Infof("Throttling request took %v, request: %s:%s", latency, r.verb, r.URL().String())
+ }
+}
+
+// Watch attempts to begin watching the requested location.
+// Returns a watch.Interface, or an error.
+func (r *Request) Watch() (watch.Interface, error) {
+ return r.WatchWithSpecificDecoders(
+ func(body io.ReadCloser) streaming.Decoder {
+ framer := r.serializers.Framer.NewFrameReader(body)
+ return streaming.NewDecoder(framer, r.serializers.StreamingSerializer)
+ },
+ r.serializers.Decoder,
+ )
+}
+
+// WatchWithSpecificDecoders attempts to begin watching the requested location with a *different* decoder.
+// Turns out that you want one "standard" decoder for the watch event and one "personal" decoder for the content
+// Returns a watch.Interface, or an error.
+func (r *Request) WatchWithSpecificDecoders(wrapperDecoderFn func(io.ReadCloser) streaming.Decoder, embeddedDecoder runtime.Decoder) (watch.Interface, error) {
+ // We specifically don't want to rate limit watches, so we
+ // don't use r.throttle here.
+ if r.err != nil {
+ return nil, r.err
+ }
+ if r.serializers.Framer == nil {
+ return nil, fmt.Errorf("watching resources is not possible with this client (content-type: %s)", r.content.ContentType)
+ }
+
+ url := r.URL().String()
+ req, err := http.NewRequest(r.verb, url, r.body)
+ if err != nil {
+ return nil, err
+ }
+ if r.ctx != nil {
+ req = req.WithContext(r.ctx)
+ }
+ req.Header = r.headers
+ client := r.client
+ if client == nil {
+ client = http.DefaultClient
+ }
+ r.backoffMgr.Sleep(r.backoffMgr.CalculateBackoff(r.URL()))
+ resp, err := client.Do(req)
+ updateURLMetrics(r, resp, err)
+ if r.baseURL != nil {
+ if err != nil {
+ r.backoffMgr.UpdateBackoff(r.baseURL, err, 0)
+ } else {
+ r.backoffMgr.UpdateBackoff(r.baseURL, err, resp.StatusCode)
+ }
+ }
+ if err != nil {
+ // The watch stream mechanism handles many common partial data errors, so closed
+ // connections can be retried in many cases.
+ if net.IsProbableEOF(err) {
+ return watch.NewEmptyWatch(), nil
+ }
+ return nil, err
+ }
+ if resp.StatusCode != http.StatusOK {
+ defer resp.Body.Close()
+ if result := r.transformResponse(resp, req); result.err != nil {
+ return nil, result.err
+ }
+ return nil, fmt.Errorf("for request '%+v', got status: %v", url, resp.StatusCode)
+ }
+ wrapperDecoder := wrapperDecoderFn(resp.Body)
+ return watch.NewStreamWatcher(restclientwatch.NewDecoder(wrapperDecoder, embeddedDecoder)), nil
+}
+
+// updateURLMetrics is a convenience function for pushing metrics.
+// It also handles corner cases for incomplete/invalid request data.
+func updateURLMetrics(req *Request, resp *http.Response, err error) {
+ url := "none"
+ if req.baseURL != nil {
+ url = req.baseURL.Host
+ }
+
+ // Errors can be arbitrary strings. Unbound label cardinality is not suitable for a metric
+ // system so we just report them as `<error>`.
+ if err != nil {
+ metrics.RequestResult.Increment("<error>", req.verb, url)
+ } else {
+ //Metrics for failure codes
+ metrics.RequestResult.Increment(strconv.Itoa(resp.StatusCode), req.verb, url)
+ }
+}
+
+// Stream formats and executes the request, and offers streaming of the response.
+// Returns io.ReadCloser which could be used for streaming of the response, or an error
+// Any non-2xx http status code causes an error. If we get a non-2xx code, we try to convert the body into an APIStatus object.
+// If we can, we return that as an error. Otherwise, we create an error that lists the http status and the content of the response.
+func (r *Request) Stream() (io.ReadCloser, error) {
+ if r.err != nil {
+ return nil, r.err
+ }
+
+ r.tryThrottle()
+
+ url := r.URL().String()
+ req, err := http.NewRequest(r.verb, url, nil)
+ if err != nil {
+ return nil, err
+ }
+ if r.ctx != nil {
+ req = req.WithContext(r.ctx)
+ }
+ req.Header = r.headers
+ client := r.client
+ if client == nil {
+ client = http.DefaultClient
+ }
+ r.backoffMgr.Sleep(r.backoffMgr.CalculateBackoff(r.URL()))
+ resp, err := client.Do(req)
+ updateURLMetrics(r, resp, err)
+ if r.baseURL != nil {
+ if err != nil {
+ r.backoffMgr.UpdateBackoff(r.URL(), err, 0)
+ } else {
+ r.backoffMgr.UpdateBackoff(r.URL(), err, resp.StatusCode)
+ }
+ }
+ if err != nil {
+ return nil, err
+ }
+
+ switch {
+ case (resp.StatusCode >= 200) && (resp.StatusCode < 300):
+ return resp.Body, nil
+
+ default:
+ // ensure we close the body before returning the error
+ defer resp.Body.Close()
+
+ result := r.transformResponse(resp, req)
+ err := result.Error()
+ if err == nil {
+ err = fmt.Errorf("%d while accessing %v: %s", result.statusCode, url, string(result.body))
+ }
+ return nil, err
+ }
+}
+
+// request connects to the server and invokes the provided function when a server response is
+// received. It handles retry behavior and up front validation of requests. It will invoke
+// fn at most once. It will return an error if a problem occurred prior to connecting to the
+// server - the provided function is responsible for handling server errors.
+func (r *Request) request(fn func(*http.Request, *http.Response)) error {
+ //Metrics for total request latency
+ start := time.Now()
+ defer func() {
+ metrics.RequestLatency.Observe(r.verb, r.finalURLTemplate(), time.Since(start))
+ }()
+
+ if r.err != nil {
+ klog.V(4).Infof("Error in request: %v", r.err)
+ return r.err
+ }
+
+ // TODO: added to catch programmer errors (invoking operations with an object with an empty namespace)
+ if (r.verb == "GET" || r.verb == "PUT" || r.verb == "DELETE") && r.namespaceSet && len(r.resourceName) > 0 && len(r.namespace) == 0 {
+ return fmt.Errorf("an empty namespace may not be set when a resource name is provided")
+ }
+ if (r.verb == "POST") && r.namespaceSet && len(r.namespace) == 0 {
+ return fmt.Errorf("an empty namespace may not be set during creation")
+ }
+
+ client := r.client
+ if client == nil {
+ client = http.DefaultClient
+ }
+
+ // Right now we make about ten retry attempts if we get a Retry-After response.
+ maxRetries := 10
+ retries := 0
+ for {
+ url := r.URL().String()
+ req, err := http.NewRequest(r.verb, url, r.body)
+ if err != nil {
+ return err
+ }
+ if r.timeout > 0 {
+ if r.ctx == nil {
+ r.ctx = context.Background()
+ }
+ var cancelFn context.CancelFunc
+ r.ctx, cancelFn = context.WithTimeout(r.ctx, r.timeout)
+ defer cancelFn()
+ }
+ if r.ctx != nil {
+ req = req.WithContext(r.ctx)
+ }
+ req.Header = r.headers
+
+ r.backoffMgr.Sleep(r.backoffMgr.CalculateBackoff(r.URL()))
+ if retries > 0 {
+ // We are retrying the request that we already send to apiserver
+ // at least once before.
+ // This request should also be throttled with the client-internal throttler.
+ r.tryThrottle()
+ }
+ resp, err := client.Do(req)
+ updateURLMetrics(r, resp, err)
+ if err != nil {
+ r.backoffMgr.UpdateBackoff(r.URL(), err, 0)
+ } else {
+ r.backoffMgr.UpdateBackoff(r.URL(), err, resp.StatusCode)
+ }
+ if err != nil {
+ // "Connection reset by peer" is usually a transient error.
+ // Thus in case of "GET" operations, we simply retry it.
+ // We are not automatically retrying "write" operations, as
+ // they are not idempotent.
+ if !net.IsConnectionReset(err) || r.verb != "GET" {
+ return err
+ }
+ // For the purpose of retry, we set the artificial "retry-after" response.
+ // TODO: Should we clean the original response if it exists?
+ resp = &http.Response{
+ StatusCode: http.StatusInternalServerError,
+ Header: http.Header{"Retry-After": []string{"1"}},
+ Body: ioutil.NopCloser(bytes.NewReader([]byte{})),
+ }
+ }
+
+ done := func() bool {
+ // Ensure the response body is fully read and closed
+ // before we reconnect, so that we reuse the same TCP
+ // connection.
+ defer func() {
+ const maxBodySlurpSize = 2 << 10
+ if resp.ContentLength <= maxBodySlurpSize {
+ io.Copy(ioutil.Discard, &io.LimitedReader{R: resp.Body, N: maxBodySlurpSize})
+ }
+ resp.Body.Close()
+ }()
+
+ retries++
+ if seconds, wait := checkWait(resp); wait && retries < maxRetries {
+ if seeker, ok := r.body.(io.Seeker); ok && r.body != nil {
+ _, err := seeker.Seek(0, 0)
+ if err != nil {
+ klog.V(4).Infof("Could not retry request, can't Seek() back to beginning of body for %T", r.body)
+ fn(req, resp)
+ return true
+ }
+ }
+
+ klog.V(4).Infof("Got a Retry-After %ds response for attempt %d to %v", seconds, retries, url)
+ r.backoffMgr.Sleep(time.Duration(seconds) * time.Second)
+ return false
+ }
+ fn(req, resp)
+ return true
+ }()
+ if done {
+ return nil
+ }
+ }
+}
+
+// Do formats and executes the request. Returns a Result object for easy response
+// processing.
+//
+// Error type:
+// * If the request can't be constructed, or an error happened earlier while building its
+// arguments: *RequestConstructionError
+// * If the server responds with a status: *errors.StatusError or *errors.UnexpectedObjectError
+// * http.Client.Do errors are returned directly.
+func (r *Request) Do() Result {
+ r.tryThrottle()
+
+ var result Result
+ err := r.request(func(req *http.Request, resp *http.Response) {
+ result = r.transformResponse(resp, req)
+ })
+ if err != nil {
+ return Result{err: err}
+ }
+ return result
+}
+
+// DoRaw executes the request but does not process the response body.
+func (r *Request) DoRaw() ([]byte, error) {
+ r.tryThrottle()
+
+ var result Result
+ err := r.request(func(req *http.Request, resp *http.Response) {
+ result.body, result.err = ioutil.ReadAll(resp.Body)
+ glogBody("Response Body", result.body)
+ if resp.StatusCode < http.StatusOK || resp.StatusCode > http.StatusPartialContent {
+ result.err = r.transformUnstructuredResponseError(resp, req, result.body)
+ }
+ })
+ if err != nil {
+ return nil, err
+ }
+ return result.body, result.err
+}
+
+// transformResponse converts an API response into a structured API object
+func (r *Request) transformResponse(resp *http.Response, req *http.Request) Result {
+ var body []byte
+ if resp.Body != nil {
+ data, err := ioutil.ReadAll(resp.Body)
+ switch err.(type) {
+ case nil:
+ body = data
+ case http2.StreamError:
+ // This is trying to catch the scenario that the server may close the connection when sending the
+ // response body. This can be caused by server timeout due to a slow network connection.
+ // TODO: Add test for this. Steps may be:
+ // 1. client-go (or kubectl) sends a GET request.
+ // 2. Apiserver sends back the headers and then part of the body
+ // 3. Apiserver closes connection.
+ // 4. client-go should catch this and return an error.
+ klog.V(2).Infof("Stream error %#v when reading response body, may be caused by closed connection.", err)
+ streamErr := fmt.Errorf("Stream error %#v when reading response body, may be caused by closed connection. Please retry.", err)
+ return Result{
+ err: streamErr,
+ }
+ default:
+ klog.Errorf("Unexpected error when reading response body: %#v", err)
+ unexpectedErr := fmt.Errorf("Unexpected error %#v when reading response body. Please retry.", err)
+ return Result{
+ err: unexpectedErr,
+ }
+ }
+ }
+
+ glogBody("Response Body", body)
+
+ // verify the content type is accurate
+ contentType := resp.Header.Get("Content-Type")
+ decoder := r.serializers.Decoder
+ if len(contentType) > 0 && (decoder == nil || (len(r.content.ContentType) > 0 && contentType != r.content.ContentType)) {
+ mediaType, params, err := mime.ParseMediaType(contentType)
+ if err != nil {
+ return Result{err: errors.NewInternalError(err)}
+ }
+ decoder, err = r.serializers.RenegotiatedDecoder(mediaType, params)
+ if err != nil {
+ // if we fail to negotiate a decoder, treat this as an unstructured error
+ switch {
+ case resp.StatusCode == http.StatusSwitchingProtocols:
+ // no-op, we've been upgraded
+ case resp.StatusCode < http.StatusOK || resp.StatusCode > http.StatusPartialContent:
+ return Result{err: r.transformUnstructuredResponseError(resp, req, body)}
+ }
+ return Result{
+ body: body,
+ contentType: contentType,
+ statusCode: resp.StatusCode,
+ }
+ }
+ }
+
+ switch {
+ case resp.StatusCode == http.StatusSwitchingProtocols:
+ // no-op, we've been upgraded
+ case resp.StatusCode < http.StatusOK || resp.StatusCode > http.StatusPartialContent:
+ // calculate an unstructured error from the response which the Result object may use if the caller
+ // did not return a structured error.
+ retryAfter, _ := retryAfterSeconds(resp)
+ err := r.newUnstructuredResponseError(body, isTextResponse(resp), resp.StatusCode, req.Method, retryAfter)
+ return Result{
+ body: body,
+ contentType: contentType,
+ statusCode: resp.StatusCode,
+ decoder: decoder,
+ err: err,
+ }
+ }
+
+ return Result{
+ body: body,
+ contentType: contentType,
+ statusCode: resp.StatusCode,
+ decoder: decoder,
+ }
+}
+
+// truncateBody decides if the body should be truncated, based on the glog Verbosity.
+func truncateBody(body string) string {
+ max := 0
+ switch {
+ case bool(klog.V(10)):
+ return body
+ case bool(klog.V(9)):
+ max = 10240
+ case bool(klog.V(8)):
+ max = 1024
+ }
+
+ if len(body) <= max {
+ return body
+ }
+
+ return body[:max] + fmt.Sprintf(" [truncated %d chars]", len(body)-max)
+}
+
+// glogBody logs a body output that could be either JSON or protobuf. It explicitly guards against
+// allocating a new string for the body output unless necessary. Uses a simple heuristic to determine
+// whether the body is printable.
+func glogBody(prefix string, body []byte) {
+ if klog.V(8) {
+ if bytes.IndexFunc(body, func(r rune) bool {
+ return r < 0x0a
+ }) != -1 {
+ klog.Infof("%s:\n%s", prefix, truncateBody(hex.Dump(body)))
+ } else {
+ klog.Infof("%s: %s", prefix, truncateBody(string(body)))
+ }
+ }
+}
+
+// maxUnstructuredResponseTextBytes is an upper bound on how much output to include in the unstructured error.
+const maxUnstructuredResponseTextBytes = 2048
+
+// transformUnstructuredResponseError handles an error from the server that is not in a structured form.
+// It is expected to transform any response that is not recognizable as a clear server sent error from the
+// K8S API using the information provided with the request. In practice, HTTP proxies and client libraries
+// introduce a level of uncertainty to the responses returned by servers that in common use result in
+// unexpected responses. The rough structure is:
+//
+// 1. Assume the server sends you something sane - JSON + well defined error objects + proper codes
+// - this is the happy path
+// - when you get this output, trust what the server sends
+// 2. Guard against empty fields / bodies in received JSON and attempt to cull sufficient info from them to
+// generate a reasonable facsimile of the original failure.
+// - Be sure to use a distinct error type or flag that allows a client to distinguish between this and error 1 above
+// 3. Handle true disconnect failures / completely malformed data by moving up to a more generic client error
+// 4. Distinguish between various connection failures like SSL certificates, timeouts, proxy errors, unexpected
+// initial contact, the presence of mismatched body contents from posted content types
+// - Give these a separate distinct error type and capture as much as possible of the original message
+//
+// TODO: introduce transformation of generic http.Client.Do() errors that separates 4.
+func (r *Request) transformUnstructuredResponseError(resp *http.Response, req *http.Request, body []byte) error {
+ if body == nil && resp.Body != nil {
+ if data, err := ioutil.ReadAll(&io.LimitedReader{R: resp.Body, N: maxUnstructuredResponseTextBytes}); err == nil {
+ body = data
+ }
+ }
+ retryAfter, _ := retryAfterSeconds(resp)
+ return r.newUnstructuredResponseError(body, isTextResponse(resp), resp.StatusCode, req.Method, retryAfter)
+}
+
+// newUnstructuredResponseError instantiates the appropriate generic error for the provided input. It also logs the body.
+func (r *Request) newUnstructuredResponseError(body []byte, isTextResponse bool, statusCode int, method string, retryAfter int) error {
+ // cap the amount of output we create
+ if len(body) > maxUnstructuredResponseTextBytes {
+ body = body[:maxUnstructuredResponseTextBytes]
+ }
+
+ message := "unknown"
+ if isTextResponse {
+ message = strings.TrimSpace(string(body))
+ }
+ var groupResource schema.GroupResource
+ if len(r.resource) > 0 {
+ groupResource.Group = r.content.GroupVersion.Group
+ groupResource.Resource = r.resource
+ }
+ return errors.NewGenericServerResponse(
+ statusCode,
+ method,
+ groupResource,
+ r.resourceName,
+ message,
+ retryAfter,
+ true,
+ )
+}
+
+// isTextResponse returns true if the response appears to be a textual media type.
+func isTextResponse(resp *http.Response) bool {
+ contentType := resp.Header.Get("Content-Type")
+ if len(contentType) == 0 {
+ return true
+ }
+ media, _, err := mime.ParseMediaType(contentType)
+ if err != nil {
+ return false
+ }
+ return strings.HasPrefix(media, "text/")
+}
+
+// checkWait returns true along with a number of seconds if the server instructed us to wait
+// before retrying.
+func checkWait(resp *http.Response) (int, bool) {
+ switch r := resp.StatusCode; {
+ // any 500 error code and 429 can trigger a wait
+ case r == http.StatusTooManyRequests, r >= 500:
+ default:
+ return 0, false
+ }
+ i, ok := retryAfterSeconds(resp)
+ return i, ok
+}
+
+// retryAfterSeconds returns the value of the Retry-After header and true, or 0 and false if
+// the header was missing or not a valid number.
+func retryAfterSeconds(resp *http.Response) (int, bool) {
+ if h := resp.Header.Get("Retry-After"); len(h) > 0 {
+ if i, err := strconv.Atoi(h); err == nil {
+ return i, true
+ }
+ }
+ return 0, false
+}
+
+// Result contains the result of calling Request.Do().
+type Result struct {
+ body []byte
+ contentType string
+ err error
+ statusCode int
+
+ decoder runtime.Decoder
+}
+
+// Raw returns the raw result.
+func (r Result) Raw() ([]byte, error) {
+ return r.body, r.err
+}
+
+// Get returns the result as an object, which means it passes through the decoder.
+// If the returned object is of type Status and has .Status != StatusSuccess, the
+// additional information in Status will be used to enrich the error.
+func (r Result) Get() (runtime.Object, error) {
+ if r.err != nil {
+ // Check whether the result has a Status object in the body and prefer that.
+ return nil, r.Error()
+ }
+ if r.decoder == nil {
+ return nil, fmt.Errorf("serializer for %s doesn't exist", r.contentType)
+ }
+
+ // decode, but if the result is Status return that as an error instead.
+ out, _, err := r.decoder.Decode(r.body, nil, nil)
+ if err != nil {
+ return nil, err
+ }
+ switch t := out.(type) {
+ case *metav1.Status:
+ // any status besides StatusSuccess is considered an error.
+ if t.Status != metav1.StatusSuccess {
+ return nil, errors.FromObject(t)
+ }
+ }
+ return out, nil
+}
+
+// StatusCode returns the HTTP status code of the request. (Only valid if no
+// error was returned.)
+func (r Result) StatusCode(statusCode *int) Result {
+ *statusCode = r.statusCode
+ return r
+}
+
+// Into stores the result into obj, if possible. If obj is nil it is ignored.
+// If the returned object is of type Status and has .Status != StatusSuccess, the
+// additional information in Status will be used to enrich the error.
+func (r Result) Into(obj runtime.Object) error {
+ if r.err != nil {
+ // Check whether the result has a Status object in the body and prefer that.
+ return r.Error()
+ }
+ if r.decoder == nil {
+ return fmt.Errorf("serializer for %s doesn't exist", r.contentType)
+ }
+ if len(r.body) == 0 {
+ return fmt.Errorf("0-length response with status code: %d and content type: %s",
+ r.statusCode, r.contentType)
+ }
+
+ out, _, err := r.decoder.Decode(r.body, nil, obj)
+ if err != nil || out == obj {
+ return err
+ }
+ // if a different object is returned, see if it is Status and avoid double decoding
+ // the object.
+ switch t := out.(type) {
+ case *metav1.Status:
+ // any status besides StatusSuccess is considered an error.
+ if t.Status != metav1.StatusSuccess {
+ return errors.FromObject(t)
+ }
+ }
+ return nil
+}
+
+// WasCreated updates the provided bool pointer to whether the server returned
+// 201 created or a different response.
+func (r Result) WasCreated(wasCreated *bool) Result {
+ *wasCreated = r.statusCode == http.StatusCreated
+ return r
+}
+
+// Error returns the error executing the request, nil if no error occurred.
+// If the returned object is of type Status and has Status != StatusSuccess, the
+// additional information in Status will be used to enrich the error.
+// See the Request.Do() comment for what errors you might get.
+func (r Result) Error() error {
+ // if we have received an unexpected server error, and we have a body and decoder, we can try to extract
+ // a Status object.
+ if r.err == nil || !errors.IsUnexpectedServerError(r.err) || len(r.body) == 0 || r.decoder == nil {
+ return r.err
+ }
+
+ // attempt to convert the body into a Status object
+ // to be backwards compatible with old servers that do not return a version, default to "v1"
+ out, _, err := r.decoder.Decode(r.body, &schema.GroupVersionKind{Version: "v1"}, nil)
+ if err != nil {
+ klog.V(5).Infof("body was not decodable (unable to check for Status): %v", err)
+ return r.err
+ }
+ switch t := out.(type) {
+ case *metav1.Status:
+ // because we default the kind, we *must* check for StatusFailure
+ if t.Status == metav1.StatusFailure {
+ return errors.FromObject(t)
+ }
+ }
+ return r.err
+}
+
+// NameMayNotBe specifies strings that cannot be used as names specified as path segments (like the REST API or etcd store)
+var NameMayNotBe = []string{".", ".."}
+
+// NameMayNotContain specifies substrings that cannot be used in names specified as path segments (like the REST API or etcd store)
+var NameMayNotContain = []string{"/", "%"}
+
+// IsValidPathSegmentName validates the name can be safely encoded as a path segment
+func IsValidPathSegmentName(name string) []string {
+ for _, illegalName := range NameMayNotBe {
+ if name == illegalName {
+ return []string{fmt.Sprintf(`may not be '%s'`, illegalName)}
+ }
+ }
+
+ var errors []string
+ for _, illegalContent := range NameMayNotContain {
+ if strings.Contains(name, illegalContent) {
+ errors = append(errors, fmt.Sprintf(`may not contain '%s'`, illegalContent))
+ }
+ }
+
+ return errors
+}
+
+// IsValidPathSegmentPrefix validates the name can be used as a prefix for a name which will be encoded as a path segment
+// It does not check for exact matches with disallowed names, since an arbitrary suffix might make the name valid
+func IsValidPathSegmentPrefix(name string) []string {
+ var errors []string
+ for _, illegalContent := range NameMayNotContain {
+ if strings.Contains(name, illegalContent) {
+ errors = append(errors, fmt.Sprintf(`may not contain '%s'`, illegalContent))
+ }
+ }
+
+ return errors
+}
+
+// ValidatePathSegmentName validates the name can be safely encoded as a path segment
+func ValidatePathSegmentName(name string, prefix bool) []string {
+ if prefix {
+ return IsValidPathSegmentPrefix(name)
+ }
+ return IsValidPathSegmentName(name)
+}