databricks-cli/retries/retries.go

76 lines
1.5 KiB
Go

package retries
import (
"context"
"fmt"
"log"
"math/rand"
"strings"
"time"
)
type Err struct {
Err error
Halt bool
}
func Halt(err error) *Err {
return &Err{err, true}
}
func Continue(err error) *Err {
return &Err{err, false}
}
func Continues(msg string) *Err {
return Continue(fmt.Errorf(msg))
}
func Continuef(format string, err error, args ...interface{}) *Err {
wrapped := fmt.Errorf(format, append([]interface{}{err}, args...))
return Continue(wrapped)
}
type WaitFn func() *Err
var maxWait = 10 * time.Second
var minJitter = 50 * time.Millisecond
var maxJitter = 750 * time.Millisecond
func Wait(pctx context.Context, timeout time.Duration, fn WaitFn) error {
ctx, cancel := context.WithTimeout(pctx, timeout)
defer cancel()
var attempt int
var lastErr error
for {
attempt++
res := fn()
if res == nil {
return nil
}
if res.Halt {
return res.Err
}
lastErr = res.Err
wait := time.Duration(attempt) * time.Second
if wait > maxWait {
wait = maxWait
}
// add some random jitter
rand.Seed(time.Now().UnixNano())
jitter := rand.Intn(int(maxJitter)-int(minJitter)+1) + int(minJitter)
wait += time.Duration(jitter)
timer := time.NewTimer(wait)
log.Printf("[TRACE] %s. Sleeping %s",
strings.TrimSuffix(res.Err.Error(), "."),
wait.Round(time.Millisecond))
select {
// stop when either this or parent context times out
case <-ctx.Done():
timer.Stop()
return fmt.Errorf("timed out: %w", lastErr)
case <-timer.C:
}
}
}