update kube and vendor dependencies

With kubernetes 1.18 release of client-go, signatures on methods in
generated clientsets, dynamic, metadata, and scale clients have been
modified to accept context.Context as a first argument.
Signatures of Create, Update, and Patch methods have been updated
to accept CreateOptions, UpdateOptions and PatchOptions respectively.
Signatures of Delete and DeleteCollection methods now accept
DeleteOptions by value instead of by reference.
These changes are now accommodated with this PR and client-go
and dependencies are updated to v1.18.0

Signed-off-by: Humble Chirammal <hchiramm@redhat.com>

vendor/k8s.io/client-go/rest/request.go

@@ -30,6 +30,7 @@ import (
 	"reflect"
 	"strconv"
 	"strings"
+	"sync"
 	"time"
 
 	"golang.org/x/net/http2"
@@ -38,6 +39,7 @@ import (
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/apimachinery/pkg/runtime/serializer/streaming"
+	utilclock "k8s.io/apimachinery/pkg/util/clock"
 	"k8s.io/apimachinery/pkg/util/net"
 	"k8s.io/apimachinery/pkg/watch"
 	restclientwatch "k8s.io/client-go/rest/watch"
@@ -51,6 +53,9 @@ var (
 	// throttled (via the provided rateLimiter) for more than longThrottleLatency will
 	// be logged.
 	longThrottleLatency = 50 * time.Millisecond
+
+	// extraLongThrottleLatency defines the threshold for logging requests at log level 2.
+	extraLongThrottleLatency = 1 * time.Second
 )
 
 // HTTPClient is an interface for testing a request object.
@@ -61,8 +66,8 @@ type HTTPClient interface {
 // 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)
+	DoRaw(context.Context) ([]byte, error)
+	Stream(context.Context) (io.ReadCloser, error)
 }
 
 // RequestConstructionError is returned when there's an error assembling a request.
@@ -104,9 +109,6 @@ type Request struct {
 	// output
 	err  error
 	body io.Reader
-
-	// This is only used for per-request timeouts, deadlines, and cancellations.
-	ctx context.Context
 }
 
 // NewRequest creates a new request helper object for accessing runtime.Objects on a server.
@@ -438,13 +440,6 @@ func (r *Request) Body(obj interface{}) *Request {
 	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
@@ -548,29 +543,88 @@ func (r Request) finalURLTemplate() url.URL {
 	return *url
 }
 
-func (r *Request) tryThrottle() error {
+func (r *Request) tryThrottle(ctx context.Context) error {
 	if r.rateLimiter == nil {
 		return nil
 	}
 
 	now := time.Now()
-	var err error
-	if r.ctx != nil {
-		err = r.rateLimiter.Wait(r.ctx)
-	} else {
-		r.rateLimiter.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())
+	err := r.rateLimiter.Wait(ctx)
+
+	latency := time.Since(now)
+	if latency > longThrottleLatency {
+		klog.V(3).Infof("Throttling request took %v, request: %s:%s", latency, r.verb, r.URL().String())
 	}
+	if latency > extraLongThrottleLatency {
+		// If the rate limiter latency is very high, the log message should be printed at a higher log level,
+		// but we use a throttled logger to prevent spamming.
+		globalThrottledLogger.Infof("Throttling request took %v, request: %s:%s", latency, r.verb, r.URL().String())
+	}
+	metrics.RateLimiterLatency.Observe(r.verb, r.finalURLTemplate(), latency)
 
 	return err
 }
 
+type throttleSettings struct {
+	logLevel       klog.Level
+	minLogInterval time.Duration
+
+	lastLogTime time.Time
+	lock        sync.RWMutex
+}
+
+type throttledLogger struct {
+	clock    utilclock.PassiveClock
+	settings []*throttleSettings
+}
+
+var globalThrottledLogger = &throttledLogger{
+	clock: utilclock.RealClock{},
+	settings: []*throttleSettings{
+		{
+			logLevel:       2,
+			minLogInterval: 1 * time.Second,
+		}, {
+			logLevel:       0,
+			minLogInterval: 10 * time.Second,
+		},
+	},
+}
+
+func (b *throttledLogger) attemptToLog() (klog.Level, bool) {
+	for _, setting := range b.settings {
+		if bool(klog.V(setting.logLevel)) {
+			// Return early without write locking if possible.
+			if func() bool {
+				setting.lock.RLock()
+				defer setting.lock.RUnlock()
+				return b.clock.Since(setting.lastLogTime) >= setting.minLogInterval
+			}() {
+				setting.lock.Lock()
+				defer setting.lock.Unlock()
+				if b.clock.Since(setting.lastLogTime) >= setting.minLogInterval {
+					setting.lastLogTime = b.clock.Now()
+					return setting.logLevel, true
+				}
+			}
+			return -1, false
+		}
+	}
+	return -1, false
+}
+
+// Infof will write a log message at each logLevel specified by the reciever's throttleSettings
+// as long as it hasn't written a log message more recently than minLogInterval.
+func (b *throttledLogger) Infof(message string, args ...interface{}) {
+	if logLevel, ok := b.attemptToLog(); ok {
+		klog.V(logLevel).Infof(message, args...)
+	}
+}
+
 // Watch attempts to begin watching the requested location.
 // Returns a watch.Interface, or an error.
-func (r *Request) Watch() (watch.Interface, error) {
+func (r *Request) Watch(ctx context.Context) (watch.Interface, error) {
 	// We specifically don't want to rate limit watches, so we
 	// don't use r.rateLimiter here.
 	if r.err != nil {
@@ -582,9 +636,7 @@ func (r *Request) Watch() (watch.Interface, error) {
 	if err != nil {
 		return nil, err
 	}
-	if r.ctx != nil {
-		req = req.WithContext(r.ctx)
-	}
+	req = req.WithContext(ctx)
 	req.Header = r.headers
 	client := r.c.Client
 	if client == nil {
@@ -659,12 +711,12 @@ func updateURLMetrics(req *Request, resp *http.Response, err error) {
 // 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) {
+func (r *Request) Stream(ctx context.Context) (io.ReadCloser, error) {
 	if r.err != nil {
 		return nil, r.err
 	}
 
-	if err := r.tryThrottle(); err != nil {
+	if err := r.tryThrottle(ctx); err != nil {
 		return nil, err
 	}
 
@@ -676,9 +728,7 @@ func (r *Request) Stream() (io.ReadCloser, error) {
 	if r.body != nil {
 		req.Body = ioutil.NopCloser(r.body)
 	}
-	if r.ctx != nil {
-		req = req.WithContext(r.ctx)
-	}
+	req = req.WithContext(ctx)
 	req.Header = r.headers
 	client := r.c.Client
 	if client == nil {
@@ -746,7 +796,7 @@ func (r *Request) requestPreflightCheck() error {
 // 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 {
+func (r *Request) request(ctx context.Context, fn func(*http.Request, *http.Response)) error {
 	//Metrics for total request latency
 	start := time.Now()
 	defer func() {
@@ -767,26 +817,30 @@ func (r *Request) request(fn func(*http.Request, *http.Response)) error {
 		client = http.DefaultClient
 	}
 
+	// Throttle the first try before setting up the timeout configured on the
+	// client. We don't want a throttled client to return timeouts to callers
+	// before it makes a single request.
+	if err := r.tryThrottle(ctx); err != nil {
+		return err
+	}
+
+	if r.timeout > 0 {
+		var cancel context.CancelFunc
+		ctx, cancel = context.WithTimeout(ctx, r.timeout)
+		defer cancel()
+	}
+
 	// 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 = req.WithContext(ctx)
 		req.Header = r.headers
 
 		r.backoff.Sleep(r.backoff.CalculateBackoff(r.URL()))
@@ -794,7 +848,7 @@ func (r *Request) request(fn func(*http.Request, *http.Response)) error {
 			// 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 rate limiter.
-			if err := r.tryThrottle(); err != nil {
+			if err := r.tryThrottle(ctx); err != nil {
 				return err
 			}
 		}
@@ -806,19 +860,24 @@ func (r *Request) request(fn func(*http.Request, *http.Response)) error {
 			r.backoff.UpdateBackoff(r.URL(), err, resp.StatusCode)
 		}
 		if err != nil {
-			// "Connection reset by peer" is usually a transient error.
+			// "Connection reset by peer" or "apiserver is shutting down" are usually a transient errors.
 			// 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" {
+			if 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{})),
+			// For connection errors and apiserver shutdown errors retry.
+			if net.IsConnectionReset(err) || net.IsProbableEOF(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{})),
+				}
+			} else {
+				return err
 			}
 		}
 
@@ -864,13 +923,9 @@ func (r *Request) request(fn func(*http.Request, *http.Response)) error {
 // Error type:
 //  * If the server responds with a status: *errors.StatusError or *errors.UnexpectedObjectError
 //  * http.Client.Do errors are returned directly.
-func (r *Request) Do() Result {
-	if err := r.tryThrottle(); err != nil {
-		return Result{err: err}
-	}
-
+func (r *Request) Do(ctx context.Context) Result {
 	var result Result
-	err := r.request(func(req *http.Request, resp *http.Response) {
+	err := r.request(ctx, func(req *http.Request, resp *http.Response) {
 		result = r.transformResponse(resp, req)
 	})
 	if err != nil {
@@ -880,13 +935,9 @@ func (r *Request) Do() Result {
 }
 
 // DoRaw executes the request but does not process the response body.
-func (r *Request) DoRaw() ([]byte, error) {
-	if err := r.tryThrottle(); err != nil {
-		return nil, err
-	}
-
+func (r *Request) DoRaw(ctx context.Context) ([]byte, error) {
 	var result Result
-	err := r.request(func(req *http.Request, resp *http.Response) {
+	err := r.request(ctx, 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 {