gitea/modules/queue/backoff.go

64 lines
1.4 KiB
Go

// Copyright 2023 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package queue
import (
"context"
"time"
)
const (
backoffBegin = 50 * time.Millisecond
backoffUpper = 2 * time.Second
)
type (
backoffFuncRetErr[T any] func() (retry bool, ret T, err error)
backoffFuncErr func() (retry bool, err error)
)
func backoffRetErr[T any](ctx context.Context, begin, upper time.Duration, end <-chan time.Time, fn backoffFuncRetErr[T]) (ret T, err error) {
d := begin
for {
// check whether the context has been cancelled or has reached the deadline, return early
select {
case <-ctx.Done():
return ret, ctx.Err()
case <-end:
return ret, context.DeadlineExceeded
default:
}
// call the target function
retry, ret, err := fn()
if err != nil {
return ret, err
}
if !retry {
return ret, nil
}
// wait for a while before retrying, and also respect the context & deadline
select {
case <-ctx.Done():
return ret, ctx.Err()
case <-time.After(d):
d *= 2
if d > upper {
d = upper
}
case <-end:
return ret, context.DeadlineExceeded
}
}
}
func backoffErr(ctx context.Context, begin, upper time.Duration, end <-chan time.Time, fn backoffFuncErr) error {
_, err := backoffRetErr(ctx, begin, upper, end, func() (retry bool, ret any, err error) {
retry, err = fn()
return retry, nil, err
})
return err
}