fix trace pending

pkg/cache/redis/errors.go

@@ -20,6 +20,9 @@ func formatErr(err error, name, addr string) string {
 		case strings.HasPrefix(es, "read"):
 			return "read timeout"
 		case strings.HasPrefix(es, "dial"):
+			if strings.Contains(es, "connection refused") {
+				return "connection refused"
+			}
 			return "dial timeout"
 		case strings.HasPrefix(es, "write"):
 			return "write timeout"
@@ -29,6 +32,10 @@ func formatErr(err error, name, addr string) string {
 			return "reset"
 		case strings.Contains(es, "broken"):
 			return "broken pipe"
+		case strings.Contains(es, "pool exhausted"):
+			return "pool exhausted"
+		case strings.Contains(es, "pool closed"):
+			return "pool closed"
 		default:
 			return "unexpected err"
 		}

pkg/cache/redis/trace.go

@@ -22,13 +22,14 @@ var _internalTags = []trace.Tag{
 }
 
 type traceConn struct {
-	// tr for pipeline, if tr != nil meaning on pipeline
+	// tr parent trace.
 	tr trace.Trace
+	// trPipe for pipeline, if trPipe != nil meaning on pipeline.
+	trPipe trace.Trace
+
 	// connTag include e.g. ip,port
 	connTags []trace.Tag
 
-	ctx context.Context
-
 	// origin redis conn
 	Conn
 	pending int
@@ -39,9 +40,15 @@ type traceConn struct {
 func (t *traceConn) Do(commandName string, args ...interface{}) (reply interface{}, err error) {
 	statement := getStatement(commandName, args...)
 	defer t.slowLog(statement, time.Now())
+
 	// NOTE: ignored empty commandName
 	// current sdk will Do empty command after pipeline finished
-	if t.tr == nil || commandName == "" {
+	if commandName == "" {
+		t.pending = 0
+		t.trPipe = nil
+		return t.Conn.Do(commandName, args...)
+	}
+	if t.tr == nil {
 		return t.Conn.Do(commandName, args...)
 	}
 	tr := t.tr.Fork("", "Redis:"+commandName)
@@ -60,18 +67,19 @@ func (t *traceConn) Send(commandName string, args ...interface{}) (err error) {
 	if t.tr == nil {
 		return t.Conn.Send(commandName, args...)
 	}
-	if t.pending == 1 {
-		t.tr = t.tr.Fork("", "Redis:Pipeline")
-		t.tr.SetTag(_internalTags...)
-		t.tr.SetTag(t.connTags...)
+
+	if t.trPipe == nil {
+		t.trPipe = t.tr.Fork("", "Redis:Pipeline")
+		t.trPipe.SetTag(_internalTags...)
+		t.trPipe.SetTag(t.connTags...)
 	}
-	t.tr.SetLog(
+	t.trPipe.SetLog(
 		trace.Log(trace.LogEvent, "Send"),
 		trace.Log("db.statement", statement),
 	)
 	if err = t.Conn.Send(commandName, args...); err != nil {
-		t.tr.SetTag(trace.TagBool(trace.TagError, true))
-		t.tr.SetLog(
+		t.trPipe.SetTag(trace.TagBool(trace.TagError, true))
+		t.trPipe.SetLog(
 			trace.Log(trace.LogEvent, "Send Fail"),
 			trace.Log(trace.LogMessage, err.Error()),
 		)
@@ -81,14 +89,14 @@ func (t *traceConn) Send(commandName string, args ...interface{}) (err error) {
 
 func (t *traceConn) Flush() error {
 	defer t.slowLog("Flush", time.Now())
-	if t.tr == nil {
+	if t.trPipe == nil {
 		return t.Conn.Flush()
 	}
-	t.tr.SetLog(trace.Log(trace.LogEvent, "Flush"))
+	t.trPipe.SetLog(trace.Log(trace.LogEvent, "Flush"))
 	err := t.Conn.Flush()
 	if err != nil {
-		t.tr.SetTag(trace.TagBool(trace.TagError, true))
-		t.tr.SetLog(
+		t.trPipe.SetTag(trace.TagBool(trace.TagError, true))
+		t.trPipe.SetLog(
 			trace.Log(trace.LogEvent, "Flush Fail"),
 			trace.Log(trace.LogMessage, err.Error()),
 		)
@@ -98,14 +106,14 @@ func (t *traceConn) Flush() error {
 
 func (t *traceConn) Receive() (reply interface{}, err error) {
 	defer t.slowLog("Receive", time.Now())
-	if t.tr == nil {
+	if t.trPipe == nil {
 		return t.Conn.Receive()
 	}
-	t.tr.SetLog(trace.Log(trace.LogEvent, "Receive"))
+	t.trPipe.SetLog(trace.Log(trace.LogEvent, "Receive"))
 	reply, err = t.Conn.Receive()
 	if err != nil {
-		t.tr.SetTag(trace.TagBool(trace.TagError, true))
-		t.tr.SetLog(
+		t.trPipe.SetTag(trace.TagBool(trace.TagError, true))
+		t.trPipe.SetLog(
 			trace.Log(trace.LogEvent, "Receive Fail"),
 			trace.Log(trace.LogMessage, err.Error()),
 		)
@@ -114,8 +122,8 @@ func (t *traceConn) Receive() (reply interface{}, err error) {
 		t.pending--
 	}
 	if t.pending == 0 {
-		t.tr.Finish(nil)
-		t.tr = nil
+		t.trPipe.Finish(nil)
+		t.trPipe = nil
 	}
 	return reply, err
 }
@@ -123,6 +131,8 @@ func (t *traceConn) Receive() (reply interface{}, err error) {
 func (t *traceConn) WithContext(ctx context.Context) Conn {
 	t.Conn = t.Conn.WithContext(ctx)
 	t.tr, _ = trace.FromContext(ctx)
+	t.pending = 0
+	t.trPipe = nil
 	return t
 }
 

pkg/cache/redis/trace_test.go

@@ -190,3 +190,23 @@ func BenchmarkTraceConn(b *testing.B) {
 		c2.Close()
 	}
 }
+
+func TestTraceConnPending(t *testing.T) {
+	c, err := DialDefaultServer()
+	if err != nil {
+		t.Fatal(err)
+	}
+	tc := &traceConn{
+		Conn:             c,
+		connTags:         []trace.Tag{trace.TagString(trace.TagPeerAddress, "abc")},
+		slowLogThreshold: time.Duration(1 * time.Second),
+	}
+	err = tc.Send("SET", "a", "x")
+	if err != nil {
+		t.Fatal(err)
+	}
+	tc.Close()
+	assert.Equal(t, 1, tc.pending)
+	tc.Do("")
+	assert.Equal(t, 0, tc.pending)
+}