Merge pull request #290 from go-redis/fix/error-handling

Cleanup error handling code.

cluster.go

@@ -195,12 +195,12 @@ func (c *ClusterClient) process(cmd Cmder) {
 
 		// If there is no (real) error, we are done!
 		err := cmd.Err()
-		if err == nil || err == Nil || err == TxFailedErr {
+		if err == nil {
 			return
 		}
 
 		// On network errors try random node.
-		if isNetworkError(err) {
+		if shouldRetry(err) {
 			client, err = c.randomClient()
 			if err != nil {
 				return

error.go

@@ -25,6 +25,11 @@ func (err redisError) Error() string {
 	return err.s
 }
 
+func isInternalError(err error) bool {
+	_, ok := err.(redisError)
+	return ok
+}
+
 func isNetworkError(err error) bool {
 	if err == io.EOF {
 		return true
@@ -37,7 +42,7 @@ func isBadConn(err error, allowTimeout bool) bool {
 	if err == nil {
 		return false
 	}
-	if _, ok := err.(redisError); ok {
+	if isInternalError(err) {
 		return false
 	}
 	if allowTimeout {
@@ -53,27 +58,24 @@ func isMovedError(err error) (moved bool, ask bool, addr string) {
 		return
 	}
 
-	parts := strings.SplitN(err.Error(), " ", 3)
+	s := err.Error()
-	if len(parts) != 3 {
+	if strings.HasPrefix(s, "MOVED ") {
+		moved = true
+	} else if strings.HasPrefix(s, "ASK ") {
+		ask = true
+	} else {
 		return
 	}
 
-	switch parts[0] {
+	ind := strings.LastIndexByte(s, ' ')
-	case "MOVED":
+	if ind == -1 {
-		moved = true
+		return false, false, ""
-		addr = parts[2]
-	case "ASK":
-		ask = true
-		addr = parts[2]
 	}
-
+	addr = s[ind+1:]
 	return
 }
 
 // shouldRetry reports whether failed command should be retried.
 func shouldRetry(err error) bool {
-	if err == nil {
-		return false
-	}
 	return isNetworkError(err)
 }

redis.go

@@ -103,7 +103,7 @@ func (c *baseClient) process(cmd Cmder) {
 		if err := writeCmd(cn, cmd); err != nil {
 			c.putConn(cn, err, false)
 			cmd.setErr(err)
-			if shouldRetry(err) {
+			if err != nil && shouldRetry(err) {
 				continue
 			}
 			return
@@ -111,7 +111,7 @@ func (c *baseClient) process(cmd Cmder) {
 
 		err = cmd.readReply(cn)
 		c.putConn(cn, err, readTimeout != nil)
-		if shouldRetry(err) {
+		if err != nil && shouldRetry(err) {
 			continue
 		}