retry, client: support to log after execing some times

client/retry/backoff.go

@@ -30,10 +30,10 @@ import (
 // Option is used to customize the backoffer.
 type Option func(*Backoffer)
 
-// WithLogTimes sets the number of retries required to print a log.
-func WithLogTimes(logTimes int) Option {
+// withMinLogInterval sets the mininum log interval for retrying.
+func withMinLogInterval(interval time.Duration) Option {
 	return func(bo *Backoffer) {
-		bo.logTimes = logTimes
+		bo.logInterval = interval
 	}
 }
 
@@ -48,8 +48,10 @@ type Backoffer struct {
 	// retryableChecker is used to check if the error is retryable.
 	// By default, all errors are retryable.
 	retryableChecker func(err error) bool
-	// logTimes defines the number of retries required to print a log
-	logTimes int
+	// logInterval defines the log interval for retrying.
+	logInterval time.Duration
+	// nextLogTime is used to record the next log time.
+	nextLogTime time.Duration
 
 	attempt      int
 	next         time.Duration
@@ -71,14 +73,16 @@ func (bo *Backoffer) Exec(
 		err = fn()
 		bo.attempt++
 		if err != nil {
-			if bo.logTimes > 0 && bo.attempt%bo.logTimes == 0 {
+			if bo.logInterval > 0 && bo.nextLogTime >= bo.logInterval {
+				bo.nextLogTime %= bo.logInterval
 				log.Warn("call PD API failed and retrying", zap.String("api", fnName), zap.Int("retry-time", bo.attempt), zap.Error(err))
 			}
 		}
 		if !bo.isRetryable(err) {
 			break
 		}
 		currentInterval := bo.nextInterval()
+		bo.nextLogTime += currentInterval
 		if after == nil {
 			after = time.NewTimer(currentInterval)
 		} else {
@@ -171,6 +175,8 @@ func (bo *Backoffer) exponentialInterval() time.Duration {
 func (bo *Backoffer) resetBackoff() {
 	bo.next = bo.base
 	bo.currentTotal = 0
+	bo.attempt = 0
+	bo.nextLogTime = 0
 }
 
 // Only used for test.

client/retry/backoff_test.go

@@ -119,13 +119,28 @@ func TestBackofferWithLog(t *testing.T) {
 	lg := newZapTestLogger(conf)
 	log.ReplaceGlobals(lg.Logger, nil)
 
-	bo := InitialBackoffer(time.Millisecond*10, time.Millisecond*100, time.Millisecond*1000, WithLogTimes(10))
+	bo := InitialBackoffer(time.Millisecond*10, time.Millisecond*100, time.Millisecond*1000, withMinLogInterval(time.Millisecond*100))
 	err := bo.Exec(ctx, testFn)
 	re.ErrorIs(err, errTest)
 
-	m1 := lg.Message()
-	rfc := `["call PD API failed and retrying"] [api=testFn] [retry-time=10] [error=test]`
-	re.Contains(m1, rfc)
+	ms := lg.Messages()
+	len1 := len(ms)
+	re.Len(ms, 9)
+	rfc := `["call PD API failed and retrying"] [api=testFn] [retry-time=13] [error=test]`
+	re.Contains(ms[len(ms)-1], rfc)
+	rfc = `["call PD API failed and retrying"] [api=testFn] [retry-time=5] [error=test]`
+	re.Contains(ms[0], rfc)
+
+	bo.resetBackoff()
+	err = bo.Exec(ctx, testFn)
+	re.ErrorIs(err, errTest)
+
+	ms = lg.Messages()
+	re.Len(ms, 18)
+	rfc = `["call PD API failed and retrying"] [api=testFn] [retry-time=13] [error=test]`
+	re.Contains(ms[len(ms)-1], rfc)
+	rfc = `["call PD API failed and retrying"] [api=testFn] [retry-time=5] [error=test]`
+	re.Contains(ms[len1], rfc)
 }
 
 var errTest = errors.New("test")
@@ -165,6 +180,13 @@ func (logger *verifyLogger) Message() string {
 	return logger.w.messages[len(logger.w.messages)-1]
 }
 
+func (logger *verifyLogger) Messages() []string {
+	if logger.w.messages == nil {
+		return nil
+	}
+	return logger.w.messages
+}
+
 func newZapTestLogger(cfg *log.Config, opts ...zap.Option) verifyLogger {
 	// TestingWriter is used to write to memory.
 	// Used in the verify logger.