From 9c2344f72688aa6b4501ae9d42d6832c0d2e087f Mon Sep 17 00:00:00 2001
From: yangfengting <yangfengting@sensetime.com>
Date: Tue, 25 Jan 2022 16:36:34 +0800
Subject: [PATCH] infinite retry should also have delay

---
 go.sum        |  5 -----
 retry.go      | 22 ++++++++++++++--------
 retry_test.go |  5 +++--
 3 files changed, 17 insertions(+), 15 deletions(-)

diff --git a/go.sum b/go.sum
index 01941e6..1ca3979 100644
--- a/go.sum
+++ b/go.sum
@@ -4,7 +4,6 @@ github.com/pierrre/gotestcover v0.0.0-20160517101806-924dca7d15f0 h1:i5VIxp6QB8o
 github.com/pierrre/gotestcover v0.0.0-20160517101806-924dca7d15f0/go.mod h1:4xpMLz7RBWyB+ElzHu8Llua96TRCB3YwX+l5EP1wmHk=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
-github.com/robertkrimen/godocdown v0.0.0-20130622164427-0bfa04905481 h1:jMxcLa+VjJKhpCwbLUXAD15wJ+hhvXMLujCl3MkXpfM=
 github.com/robertkrimen/godocdown v0.0.0-20130622164427-0bfa04905481/go.mod h1:C9WhFzY47SzYBIvzFqSvHIR6ROgDo4TtdTuRaOMjF/s=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
@@ -23,16 +22,12 @@ golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210809222454-d867a43fc93e/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.0.0-20211015200801-69063c4bb744 h1:KzbpndAYEM+4oHRp9JmB2ewj0NHHxO3Z0g7Gus2O1kk=
-golang.org/x/sys v0.0.0-20211015200801-69063c4bb744/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.0.0-20211107104306-e0b2ad06fe42 h1:G2DDmludOQZoWbpCr7OKDxnl478ZBGMcOhrv+ooX/Q4=
 golang.org/x/sys v0.0.0-20211107104306-e0b2ad06fe42/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
-golang.org/x/tools v0.1.7 h1:6j8CgantCy3yc8JGBqkDLMKWqZ0RDU2g1HVgacojGWQ=
 golang.org/x/tools v0.1.7/go.mod h1:LGqMHiF4EqQNHR1JncWGqT5BVaXmza+X+BDGol+dOxo=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
diff --git a/retry.go b/retry.go
index ead1c02..3ce13dd 100644
--- a/retry.go
+++ b/retry.go
@@ -75,10 +75,10 @@ type RetryableFunc func() error
 func Do(retryableFunc RetryableFunc, opts ...Option) error {
 	var n uint
 
-	//default
+	// default
 	config := newDefaultRetryConfig()
 
-	//apply opts
+	// apply opts
 	for _, opt := range opts {
 		opt(config)
 	}
@@ -90,6 +90,8 @@ func Do(retryableFunc RetryableFunc, opts ...Option) error {
 	// Setting attempts to 0 means we'll retry until we succeed
 	if config.attempts == 0 {
 		for err := retryableFunc(); err != nil; err = retryableFunc() {
+			n++
+			<-time.After(delay(config, n, err))
 		}
 
 		return nil
@@ -120,13 +122,8 @@ func Do(retryableFunc RetryableFunc, opts ...Option) error {
 				break
 			}
 
-			delayTime := config.delayType(n, err, config)
-			if config.maxDelay > 0 && delayTime > config.maxDelay {
-				delayTime = config.maxDelay
-			}
-
 			select {
-			case <-time.After(delayTime):
+			case <-time.After(delay(config, n, err)):
 			case <-config.context.Done():
 				if config.lastErrorOnly {
 					return config.context.Err()
@@ -220,3 +217,12 @@ func unpackUnrecoverable(err error) error {
 
 	return err
 }
+
+func delay(config *Config, n uint, err error) time.Duration {
+	delayTime := config.delayType(n, err, config)
+	if config.maxDelay > 0 && delayTime > config.maxDelay {
+		delayTime = config.maxDelay
+	}
+
+	return delayTime
+}
diff --git a/retry_test.go b/retry_test.go
index 2749465..0506813 100644
--- a/retry_test.go
+++ b/retry_test.go
@@ -86,6 +86,7 @@ func TestZeroAttemptsWithError(t *testing.T) {
 			return nil
 		},
 		Attempts(0),
+		MaxDelay(time.Nanosecond),
 	)
 	assert.NoError(t, err)
 
@@ -195,8 +196,8 @@ func TestMaxDelay(t *testing.T) {
 	)
 	dur := time.Since(start)
 	assert.Error(t, err)
-	assert.True(t, dur > 170*time.Millisecond, "5 times with maximum delay retry is longer than 170ms")
-	assert.True(t, dur < 200*time.Millisecond, "5 times with maximum delay retry is shorter than 200ms")
+	assert.True(t, dur > 120*time.Millisecond, "5 times with maximum delay retry is longer than 120ms")
+	assert.True(t, dur < 205*time.Millisecond, "5 times with maximum delay retry is shorter than 205ms")
 }
 
 func TestBackOffDelay(t *testing.T) {