pkg/runtime/{compose,standalone}/service.go: prevent duplicate flags

If storj-up is used to add a flag that already exists, check first
if the flag already exists, and replace the old flag if it does.

This change also fixes a bug that removed the script files if the
persist or remove flag command is used in standalone mode.

Change-Id: I419882c2bce8fbbaf2ca1dc5dc7edec432e88429

pkg/runtime/compose/service.go

@@ -230,6 +230,15 @@ func (s *Service) AddFlag(flag string) error {
 			if err != nil {
 				return err
 			}
+			eqIndex := strings.Index(rendered, "=")
+			if eqIndex >= 0 {
+				commandIndex := slices.IndexFunc(s.project.Services[ix].Command, func(command string) bool {
+					return strings.HasPrefix(command, rendered[:eqIndex+1])
+				})
+				if commandIndex >= 0 {
+					s.project.Services[ix].Command = slices.Delete(s.project.Services[ix].Command, commandIndex, commandIndex+1)
+				}
+			}
 			s.project.Services[ix].Command = append(s.project.Services[ix].Command, rendered)
 		}
 	}

pkg/runtime/standalone/service.go

@@ -8,7 +8,7 @@ import (
 	"regexp"
 	"strings"
 
-	"github.com/zeebo/errs"
+	"golang.org/x/exp/slices"
 
 	"storj.io/storj-up/pkg/runtime/runtime"
 )
@@ -50,11 +50,13 @@ func (s *service) Labels() []string {
 }
 
 func (s *service) RemoveFlag(flag string) error {
-	return errs.New("RemoveFlag for Standalone is not yet implemented")
+	fmt.Println("RemoveFlag for Standalone is not yet implemented!")
+	return nil
 }
 
 func (s *service) Persist(dir string) error {
-	return errs.New("Standalone runner doesn't use containers. No need to persist directories.")
+	// NOOP: Standalone runner doesn't use containers. No need to persist directories
+	return nil
 }
 
 func (s *service) ChangeImage(func(string) string) error {
@@ -105,6 +107,15 @@ func (s *service) AddFlag(flag string) error {
 	if err != nil {
 		return err
 	}
+	eqIndex := strings.Index(f, "=")
+	if eqIndex >= 0 {
+		commandIndex := slices.IndexFunc(s.Command, func(command string) bool {
+			return strings.HasPrefix(command, f[:eqIndex+1])
+		})
+		if commandIndex >= 0 {
+			s.Command = slices.Delete(s.Command, commandIndex, commandIndex+1)
+		}
+	}
 	s.Command = append(s.Command, f)
 	return nil
 }