Retry timeout and retryable error

Author: vmihailenco

cluster.go

@@ -810,7 +810,7 @@ func (c *ClusterClient) _process(ctx context.Context, cmd Cmder) error {
 			continue
 		}
 
-		if isRetryableError(lastErr, cmd.readTimeout() == nil) {
+		if shouldRetry(lastErr, cmd.readTimeout() == nil) {
 			// First retry the same node.
 			if attempt == 0 {
 				continue
@@ -1466,7 +1466,7 @@ func (c *ClusterClient) Watch(ctx context.Context, fn func(*Tx) error, keys ...s
 			continue
 		}
 
-		if isRetryableError(err, true) {
+		if shouldRetry(err, true) {
 			continue
 		}
 

error.go

@@ -24,15 +24,16 @@ type Error interface {
 
 var _ Error = proto.RedisError("")
 
-func isRetryableError(err error, retryTimeout bool) bool {
+func shouldRetry(err error, retryTimeout bool) bool {
 	switch err {
+	case io.EOF, io.ErrUnexpectedEOF:
+		return true
 	case nil, context.Canceled, context.DeadlineExceeded:
 		return false
-	case io.EOF:
-		return true
 	}
-	if netErr, ok := err.(net.Error); ok {
-		if netErr.Timeout() {
+
+	if v, ok := err.(timeoutError); ok {
+		if v.Timeout() {
 			return retryTimeout
 		}
 		return true
@@ -51,6 +52,7 @@ func isRetryableError(err error, retryTimeout bool) bool {
 	if strings.HasPrefix(s, "CLUSTERDOWN ") {
 		return true
 	}
+
 	return false
 }
 
@@ -63,16 +65,19 @@ func isBadConn(err error, allowTimeout bool) bool {
 	if err == nil {
 		return false
 	}
+
 	if isRedisError(err) {
 		// Close connections in read only state in case domain addr is used
 		// and domain resolves to a different Redis Server. See #790.
 		return isReadOnlyError(err)
 	}
+
 	if allowTimeout {
 		if netErr, ok := err.(net.Error); ok && netErr.Timeout() {
-			return false
+			return !netErr.Temporary()
 		}
 	}
+
 	return true
 }
 
@@ -106,3 +111,9 @@ func isLoadingError(err error) bool {
 func isReadOnlyError(err error) bool {
 	return strings.HasPrefix(err.Error(), "READONLY ")
 }
+
+//------------------------------------------------------------------------------
+
+type timeoutError interface {
+	Timeout() bool
+}

main_test.go

@@ -332,7 +332,7 @@ func startSentinel(port, masterName, masterPort string) (*redisProcess, error) {
 type badConnError string
 
 func (e badConnError) Error() string   { return string(e) }
-func (e badConnError) Timeout() bool   { return false }
+func (e badConnError) Timeout() bool   { return true }
 func (e badConnError) Temporary() bool { return false }
 
 type badConn struct {

redis.go

@@ -345,7 +345,7 @@ func (c *baseClient) _process(ctx context.Context, cmd Cmder) error {
 			if err == nil {
 				return nil
 			}
-			retry = isRetryableError(err, retryTimeout)
+			retry = shouldRetry(err, retryTimeout)
 			return err
 		})
 		if err == nil || !retry {
@@ -430,7 +430,7 @@ func (c *baseClient) _generalProcessPipeline(
 			canRetry, err = p(ctx, cn, cmds)
 			return err
 		})
-		if lastErr == nil || !canRetry || !isRetryableError(lastErr, true) {
+		if lastErr == nil || !canRetry || !shouldRetry(lastErr, true) {
 			return lastErr
 		}
 	}

ring.go

@@ -597,7 +597,7 @@ func (c *Ring) _process(ctx context.Context, cmd Cmder) error {
 		}
 
 		lastErr = shard.Client.Process(ctx, cmd)
-		if lastErr == nil || !isRetryableError(lastErr, cmd.readTimeout() == nil) {
+		if lastErr == nil || !shouldRetry(lastErr, cmd.readTimeout() == nil) {
 			return lastErr
 		}
 	}