robocar-arduino/vendor/github.com/cenkalti/backoff/context.go
2019-12-18 23:21:52 +01:00

64 lines
1.1 KiB
Go

package backoff
import (
"context"
"time"
)
// BackOffContext is a backoff policy that stops retrying after the context
// is canceled.
type BackOffContext interface {
BackOff
Context() context.Context
}
type backOffContext struct {
BackOff
ctx context.Context
}
// WithContext returns a BackOffContext with context ctx
//
// ctx must not be nil
func WithContext(b BackOff, ctx context.Context) BackOffContext {
if ctx == nil {
panic("nil context")
}
if b, ok := b.(*backOffContext); ok {
return &backOffContext{
BackOff: b.BackOff,
ctx: ctx,
}
}
return &backOffContext{
BackOff: b,
ctx: ctx,
}
}
func ensureContext(b BackOff) BackOffContext {
if cb, ok := b.(BackOffContext); ok {
return cb
}
return WithContext(b, context.Background())
}
func (b *backOffContext) Context() context.Context {
return b.ctx
}
func (b *backOffContext) NextBackOff() time.Duration {
select {
case <-b.ctx.Done():
return Stop
default:
}
next := b.BackOff.NextBackOff()
if deadline, ok := b.ctx.Deadline(); ok && deadline.Sub(time.Now()) < next {
return Stop
}
return next
}