Code maintenance: OS user abstraction interface

internal/alpine/alpine.go

@@ -1,9 +1,8 @@
 package alpine
 
 import (
-	"os/user"
-
 	"github.com/qdm12/gluetun/internal/os"
+	"github.com/qdm12/gluetun/internal/os/user"
 )
 
 type Configurator interface {
@@ -11,15 +10,13 @@ type Configurator interface {
 }
 
 type configurator struct {
-	openFile   os.OpenFileFunc
-	lookupUID  func(uid string) (*user.User, error)
-	lookupUser func(username string) (*user.User, error)
+	openFile os.OpenFileFunc
+	osUser   user.OSUser
 }
 
-func NewConfigurator(openFile os.OpenFileFunc) Configurator {
+func NewConfigurator(openFile os.OpenFileFunc, osUser user.OSUser) Configurator {
 	return &configurator{
-		openFile:   openFile,
-		lookupUID:  user.LookupId,
-		lookupUser: user.Lookup,
+		openFile: openFile,
+		osUser:   osUser,
 	}
 }

internal/alpine/users.go

@@ -9,7 +9,7 @@ import (
 // CreateUser creates a user in Alpine with the given UID.
 func (c *configurator) CreateUser(username string, uid int) (createdUsername string, err error) {
 	UIDStr := fmt.Sprintf("%d", uid)
-	u, err := c.lookupUID(UIDStr)
+	u, err := c.osUser.LookupID(UIDStr)
 	_, unknownUID := err.(user.UnknownUserIdError)
 	if err != nil && !unknownUID {
 		return "", fmt.Errorf("cannot create user: %w", err)
@@ -19,7 +19,7 @@ func (c *configurator) CreateUser(username string, uid int) (createdUsername str
 		}
 		return u.Username, nil
 	}
-	u, err = c.lookupUser(username)
+	u, err = c.osUser.Lookup(username)
 	_, unknownUsername := err.(user.UnknownUserError)
 	if err != nil && !unknownUsername {
 		return "", fmt.Errorf("cannot create user: %w", err)