(squash with fourth commit): add --output-folder flag

cmd/convert.go

@@ -3,6 +3,7 @@ package cmd
 import (
 	"fmt"
 	"os"
+	"path/filepath"
 
 	"github.com/kong/deck/convert"
 	"github.com/kong/deck/cprint"
@@ -16,6 +17,7 @@ var (
 	convertCmdInputFile         string
 	convertCmdOutputFile        string
 	convertCmdInputFolder       string
+	convertCmdOutputFolder      string
 )
 
 // newConvertCmd represents the convert command
@@ -54,7 +56,12 @@ can be converted into a 'konnect' configuration file.`,
 					return fmt.Errorf("getting files from directory: %w", err)
 				}
 				for _, filename := range files {
-					outputFile := filename + ".converted"
+					outputFile := filepath.Join(convertCmdOutputFolder, filepath.Base(filename))
+					if _, err := os.Stat(convertCmdOutputFolder); os.IsNotExist(err) {
+						if err := os.Mkdir(convertCmdOutputFolder, 0o700); err != nil {
+							return fmt.Errorf("creating output folder: %w", err)
+						}
+					}
 					err = convert.Convert(filename, outputFile, sourceFormat, destinationFormat)
 					if err != nil {
 						return fmt.Errorf("converting '%s' file: %v", filename, err)
@@ -81,7 +88,9 @@ can be converted into a 'konnect' configuration file.`,
 	convertCmd.Flags().StringVar(&convertCmdOutputFile, "output-file", "",
 		"file to write configuration to after conversion. Use `-` to write to stdout.")
 	convertCmd.Flags().StringVar(&convertCmdInputFolder, "input-folder", "",
-		"configuration folder to be converted. decK will append `.converted` to converted files.")
+		"configuration folder to be converted.")
+	convertCmd.Flags().StringVar(&convertCmdOutputFolder, "output-folder", "",
+		"folder to write configuration to after conversion.")
 	return convertCmd
 }