Update vendor

vendor/github.com/google/go-containerregistry/pkg/internal/retry/retry.go

@@ -0,0 +1,77 @@
+// Copyright 2019 Google LLC All Rights Reserved.
+//
+// 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 provides methods for retrying operations. It is a thin wrapper
+// around k8s.io/apimachinery/pkg/util/wait to make certain operations easier.
+package retry
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/google/go-containerregistry/pkg/internal/retry/wait"
+)
+
+// Backoff is an alias of our own wait.Backoff to avoid name conflicts with
+// the kubernetes wait package. Typing retry.Backoff is aesier than fixing
+// the wrong import every time you use wait.Backoff.
+type Backoff = wait.Backoff
+
+// This is implemented by several errors in the net package as well as our
+// transport.Error.
+type temporary interface {
+	Temporary() bool
+}
+
+// IsTemporary returns true if err implements Temporary() and it returns true.
+func IsTemporary(err error) bool {
+	if err == context.DeadlineExceeded {
+		return false
+	}
+	if te, ok := err.(temporary); ok && te.Temporary() {
+		return true
+	}
+	return false
+}
+
+// IsNotNil returns true if err is not nil.
+func IsNotNil(err error) bool {
+	return err != nil
+}
+
+// Predicate determines whether an error should be retried.
+type Predicate func(error) (retry bool)
+
+// Retry retries a given function, f, until a predicate is satisfied, using
+// exponential backoff. If the predicate is never satisfied, it will return the
+// last error returned by f.
+func Retry(f func() error, p Predicate, backoff wait.Backoff) (err error) {
+	if f == nil {
+		return fmt.Errorf("nil f passed to retry")
+	}
+	if p == nil {
+		return fmt.Errorf("nil p passed to retry")
+	}
+
+	condition := func() (bool, error) {
+		err = f()
+		if p(err) {
+			return false, nil
+		}
+		return true, err
+	}
+
+	wait.ExponentialBackoff(backoff, condition)
+	return
+}

vendor/github.com/google/go-containerregistry/pkg/internal/retry/wait/kubernetes_apimachinery_wait.go

@@ -0,0 +1,123 @@
+/*
+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 wait is a subset of k8s.io/apimachinery to avoid conflicts
+// in dependencies (specifically, logging).
+package wait
+
+import (
+	"errors"
+	"math/rand"
+	"time"
+)
+
+// Jitter returns a time.Duration between duration and duration + maxFactor *
+// duration.
+//
+// This allows clients to avoid converging on periodic behavior. If maxFactor
+// is 0.0, a suggested default value will be chosen.
+func Jitter(duration time.Duration, maxFactor float64) time.Duration {
+	if maxFactor <= 0.0 {
+		maxFactor = 1.0
+	}
+	wait := duration + time.Duration(rand.Float64()*maxFactor*float64(duration))
+	return wait
+}
+
+// ErrWaitTimeout is returned when the condition exited without success.
+var ErrWaitTimeout = errors.New("timed out waiting for the condition")
+
+// ConditionFunc returns true if the condition is satisfied, or an error
+// if the loop should be aborted.
+type ConditionFunc func() (done bool, err error)
+
+// Backoff holds parameters applied to a Backoff function.
+type Backoff struct {
+	// The initial duration.
+	Duration time.Duration
+	// Duration is multiplied by factor each iteration, if factor is not zero
+	// and the limits imposed by Steps and Cap have not been reached.
+	// Should not be negative.
+	// The jitter does not contribute to the updates to the duration parameter.
+	Factor float64
+	// The sleep at each iteration is the duration plus an additional
+	// amount chosen uniformly at random from the interval between
+	// zero and `jitter*duration`.
+	Jitter float64
+	// The remaining number of iterations in which the duration
+	// parameter may change (but progress can be stopped earlier by
+	// hitting the cap). If not positive, the duration is not
+	// changed. Used for exponential backoff in combination with
+	// Factor and Cap.
+	Steps int
+	// A limit on revised values of the duration parameter. If a
+	// multiplication by the factor parameter would make the duration
+	// exceed the cap then the duration is set to the cap and the
+	// steps parameter is set to zero.
+	Cap time.Duration
+}
+
+// Step (1) returns an amount of time to sleep determined by the
+// original Duration and Jitter and (2) mutates the provided Backoff
+// to update its Steps and Duration.
+func (b *Backoff) Step() time.Duration {
+	if b.Steps < 1 {
+		if b.Jitter > 0 {
+			return Jitter(b.Duration, b.Jitter)
+		}
+		return b.Duration
+	}
+	b.Steps--
+
+	duration := b.Duration
+
+	// calculate the next step
+	if b.Factor != 0 {
+		b.Duration = time.Duration(float64(b.Duration) * b.Factor)
+		if b.Cap > 0 && b.Duration > b.Cap {
+			b.Duration = b.Cap
+			b.Steps = 0
+		}
+	}
+
+	if b.Jitter > 0 {
+		duration = Jitter(duration, b.Jitter)
+	}
+	return duration
+}
+
+// ExponentialBackoff repeats a condition check with exponential backoff.
+//
+// It repeatedly checks the condition and then sleeps, using `backoff.Step()`
+// to determine the length of the sleep and adjust Duration and Steps.
+// Stops and returns as soon as:
+// 1. the condition check returns true or an error,
+// 2. `backoff.Steps` checks of the condition have been done, or
+// 3. a sleep truncated by the cap on duration has been completed.
+// In case (1) the returned error is what the condition function returned.
+// In all other cases, ErrWaitTimeout is returned.
+func ExponentialBackoff(backoff Backoff, condition ConditionFunc) error {
+	for backoff.Steps > 0 {
+		if ok, err := condition(); err != nil || ok {
+			return err
+		}
+		if backoff.Steps == 1 {
+			break
+		}
+		time.Sleep(backoff.Step())
+	}
+	return ErrWaitTimeout
+}