57 lines
1.3 KiB
Go
57 lines
1.3 KiB
Go
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// Copyright 2023 the Pinniped contributors. All Rights Reserved.
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// SPDX-License-Identifier: Apache-2.0
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package backoff
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import (
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"context"
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"time"
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"k8s.io/apimachinery/pkg/util/wait"
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)
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type Stepper interface {
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Step() time.Duration
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}
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func wrapConditionWithNoPanics(ctx context.Context, condition wait.ConditionWithContextFunc) (done bool, err error) {
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defer func() {
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if r := recover(); r != nil {
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if err2, ok := r.(error); ok {
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err = err2
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return
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}
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}
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}()
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return condition(ctx)
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}
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func WithContext(ctx context.Context, backoff Stepper, condition wait.ConditionWithContextFunc) error {
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// Loop forever, unless we reach one of the return statements below.
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for {
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// Stop if the context is done.
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select {
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case <-ctx.Done():
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return ctx.Err()
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default:
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}
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// Stop trying unless the condition function returns false.
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// Allow cancellation during the attempt if the condition function respects the ctx.
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if ok, err := wrapConditionWithNoPanics(ctx, condition); err != nil || ok {
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return err
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}
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// Calculate how long to wait before the next step.
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waitBeforeRetry := backoff.Step()
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// Wait before running again, allowing cancellation during the wait.
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select {
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case <-ctx.Done():
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return ctx.Err()
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case <-time.After(waitBeforeRetry):
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}
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}
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}
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