skip run empty config

cmd/commands/cmd.go

@@ -7,6 +7,7 @@ import (
 	"RedisShake/internal/writer"
 	"bytes"
 	"container/heap"
+	"errors"
 	"fmt"
 	"github.com/google/uuid"
 	"github.com/spf13/cobra"
@@ -102,7 +103,10 @@ command_writer: redis_writer, redis_writer.sentinel`,
 	}
 
 	description := "#this config file is generated by command: " + strings.Join(os.Args, " ")
-	toml := viperMap2Toml(viperMap, description)
+	toml ,err:= viperMap2Toml(viperMap, description)
+	if err != nil {
+		return "", err
+	}
 	if dryRun {
 		fmt.Println(string(toml))
 		return "", nil
@@ -119,21 +123,28 @@ command_writer: redis_writer, redis_writer.sentinel`,
 	return filePath, nil
 }
 
-func viperMap2Toml(viperMap map[string]*viper.Viper, description string) []byte {
+func viperMap2Toml(viperMap map[string]*viper.Viper, description string) ([]byte,error) {
 	var buffer bytes.Buffer
 	buffer.WriteString(description + "\n")
+	isAllConfigEmpty := true
 	for key, vp := range viperMap {
 		settings := vp.AllSettings()
 		if len(settings) == 0 {
 			continue
 		}
+		if isAllConfigEmpty {
+			isAllConfigEmpty = false
+		}
 		buffer.WriteString("[" + key + "]\n")
 		for k, v := range settings {
 			buffer.WriteString(fmt.Sprintf("%s = %#v\n", k, v))
 		}
 		buffer.WriteString("\n")
 	}
-	return buffer.Bytes()
+	if isAllConfigEmpty{
+		return []byte{},errors.New("all config empty")
+	}
+	return buffer.Bytes(),nil
 }
 
 func buildCommandRedisWriterSentinel() (*viper.Viper, *cobra.Command) {