Dmitry Sergeev
88 lines
1.6 KiB
Go
88 lines
1.6 KiB
Go
package playback
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import (
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"context"
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"time"
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)
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// attemptFunc returns whether useful media was received before the attempt ended.
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type attemptFunc func(context.Context) (becameStable bool, err error)
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type retryDecider func(error) bool
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type waitFunc func(context.Context, time.Duration) error
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func waitForRetry(ctx context.Context, delay time.Duration) error {
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timer := time.NewTimer(delay)
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defer timer.Stop()
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select {
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case <-timer.C:
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return nil
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case <-ctx.Done():
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return ctx.Err()
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}
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}
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func runWithRetry(
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ctx context.Context,
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policy RetryPolicy,
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attempt attemptFunc,
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shouldRetry retryDecider,
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wait waitFunc,
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observer retryObserver,
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) error {
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failedAttempts := 0
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for {
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becameStable, err := attempt(ctx)
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if err == nil {
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return nil
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}
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if ctx.Err() != nil {
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return ctx.Err()
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}
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if becameStable {
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failedAttempts = 0
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}
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failedAttempts++
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willRetry := shouldRetry(err) && policy.canRetry(failedAttempts)
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if !willRetry {
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if observer != nil {
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observer(retryEvent{
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FailedAttempts: failedAttempts,
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Err: err,
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WillRetry: false,
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})
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}
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return err
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}
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delay := policy.retryDelay(failedAttempts)
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if observer != nil {
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observer(retryEvent{
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FailedAttempts: failedAttempts,
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Err: err,
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RetryIn: delay,
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WillRetry: true,
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})
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}
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if err := wait(ctx, delay); err != nil {
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if ctx.Err() != nil {
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return ctx.Err()
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}
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return err
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}
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}
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}
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type retryEvent struct {
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FailedAttempts int
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Err error
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RetryIn time.Duration
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WillRetry bool
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}
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type retryObserver func(retryEvent)
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