refactor: reduce duplicate code

Signed-off-by: Ye Sijun <junnplus@gmail.com>

oci/spec_opts.go

@@ -701,11 +701,8 @@ func WithUIDGID(uid, gid uint32) SpecOpts {
 func WithUserID(uid uint32) SpecOpts {
 	return func(ctx context.Context, client Client, c *containers.Container, s *Spec) (err error) {
 		setProcess(s)
-		if c.Snapshotter == "" && c.SnapshotKey == "" {
+		setUser := func(root string) error {
-			if !isRootfsAbs(s.Root.Path) {
+			user, err := UserFromPath(root, func(u user.User) bool {
-				return errors.New("rootfs absolute path is required")
-			}
-			user, err := UserFromPath(s.Root.Path, func(u user.User) bool {
 				return u.Uid == int(uid)
 			})
 			if err != nil {
@@ -717,7 +714,12 @@ func WithUserID(uid uint32) SpecOpts {
 			}
 			s.Process.User.UID, s.Process.User.GID = uint32(user.Uid), uint32(user.Gid)
 			return nil
-
+		}
+		if c.Snapshotter == "" && c.SnapshotKey == "" {
+			if !isRootfsAbs(s.Root.Path) {
+				return errors.New("rootfs absolute path is required")
+			}
+			return setUser(s.Root.Path)
 		}
 		if c.Snapshotter == "" {
 			return errors.New("no snapshotter set for container")
@@ -732,20 +734,7 @@ func WithUserID(uid uint32) SpecOpts {
 		}
 
 		mounts = tryReadonlyMounts(mounts)
-		return mount.WithTempMount(ctx, mounts, func(root string) error {
+		return mount.WithTempMount(ctx, mounts, setUser)
-			user, err := UserFromPath(root, func(u user.User) bool {
-				return u.Uid == int(uid)
-			})
-			if err != nil {
-				if os.IsNotExist(err) || err == ErrNoUsersFound {
-					s.Process.User.UID, s.Process.User.GID = uid, 0
-					return nil
-				}
-				return err
-			}
-			s.Process.User.UID, s.Process.User.GID = uint32(user.Uid), uint32(user.Gid)
-			return nil
-		})
 	}
 }
 
@@ -759,11 +748,8 @@ func WithUsername(username string) SpecOpts {
 	return func(ctx context.Context, client Client, c *containers.Container, s *Spec) (err error) {
 		setProcess(s)
 		if s.Linux != nil {
-			if c.Snapshotter == "" && c.SnapshotKey == "" {
+			setUser := func(root string) error {
-				if !isRootfsAbs(s.Root.Path) {
+				user, err := UserFromPath(root, func(u user.User) bool {
-					return errors.New("rootfs absolute path is required")
-				}
-				user, err := UserFromPath(s.Root.Path, func(u user.User) bool {
 					return u.Name == username
 				})
 				if err != nil {
@@ -772,6 +758,12 @@ func WithUsername(username string) SpecOpts {
 				s.Process.User.UID, s.Process.User.GID = uint32(user.Uid), uint32(user.Gid)
 				return nil
 			}
+			if c.Snapshotter == "" && c.SnapshotKey == "" {
+				if !isRootfsAbs(s.Root.Path) {
+					return errors.New("rootfs absolute path is required")
+				}
+				return setUser(s.Root.Path)
+			}
 			if c.Snapshotter == "" {
 				return errors.New("no snapshotter set for container")
 			}
@@ -785,16 +777,7 @@ func WithUsername(username string) SpecOpts {
 			}
 
 			mounts = tryReadonlyMounts(mounts)
-			return mount.WithTempMount(ctx, mounts, func(root string) error {
+			return mount.WithTempMount(ctx, mounts, setUser)
-				user, err := UserFromPath(root, func(u user.User) bool {
-					return u.Name == username
-				})
-				if err != nil {
-					return err
-				}
-				s.Process.User.UID, s.Process.User.GID = uint32(user.Uid), uint32(user.Gid)
-				return nil
-			})
 		} else if s.Windows != nil {
 			s.Process.User.Username = username
 		} else {

oci/spec_opts_linux_test.go

@@ -18,6 +18,7 @@ package oci
 
 import (
 	"context"
+	"fmt"
 	"os"
 	"path/filepath"
 	"testing"
@@ -30,6 +31,123 @@ import (
 	"golang.org/x/sys/unix"
 )
 
+// nolint:gosec
+func TestWithUserID(t *testing.T) {
+	t.Parallel()
+
+	expectedPasswd := `root:x:0:0:root:/root:/bin/ash
+guest:x:405:100:guest:/dev/null:/sbin/nologin
+`
+	td := t.TempDir()
+	apply := fstest.Apply(
+		fstest.CreateDir("/etc", 0777),
+		fstest.CreateFile("/etc/passwd", []byte(expectedPasswd), 0777),
+	)
+	if err := apply.Apply(td); err != nil {
+		t.Fatalf("failed to apply: %v", err)
+	}
+	c := containers.Container{ID: t.Name()}
+	testCases := []struct {
+		userID      uint32
+		expectedUID uint32
+		expectedGID uint32
+	}{
+		{
+			userID:      0,
+			expectedUID: 0,
+			expectedGID: 0,
+		},
+		{
+			userID:      405,
+			expectedUID: 405,
+			expectedGID: 100,
+		},
+		{
+			userID:      1000,
+			expectedUID: 1000,
+			expectedGID: 0,
+		},
+	}
+	for _, testCase := range testCases {
+		t.Run(fmt.Sprintf("user %d", testCase.userID), func(t *testing.T) {
+			t.Parallel()
+			s := Spec{
+				Version: specs.Version,
+				Root: &specs.Root{
+					Path: td,
+				},
+				Linux: &specs.Linux{},
+			}
+			err := WithUserID(testCase.userID)(context.Background(), nil, &c, &s)
+			assert.NoError(t, err)
+			assert.Equal(t, testCase.expectedUID, s.Process.User.UID)
+			assert.Equal(t, testCase.expectedGID, s.Process.User.GID)
+		})
+	}
+}
+
+// nolint:gosec
+func TestWithUsername(t *testing.T) {
+	t.Parallel()
+
+	expectedPasswd := `root:x:0:0:root:/root:/bin/ash
+guest:x:405:100:guest:/dev/null:/sbin/nologin
+`
+	td := t.TempDir()
+	apply := fstest.Apply(
+		fstest.CreateDir("/etc", 0777),
+		fstest.CreateFile("/etc/passwd", []byte(expectedPasswd), 0777),
+	)
+	if err := apply.Apply(td); err != nil {
+		t.Fatalf("failed to apply: %v", err)
+	}
+	c := containers.Container{ID: t.Name()}
+	testCases := []struct {
+		user        string
+		expectedUID uint32
+		expectedGID uint32
+		err         string
+	}{
+		{
+			user:        "root",
+			expectedUID: 0,
+			expectedGID: 0,
+		},
+		{
+			user:        "guest",
+			expectedUID: 405,
+			expectedGID: 100,
+		},
+		{
+			user: "1000",
+			err:  "no users found",
+		},
+		{
+			user: "unknown",
+			err:  "no users found",
+		},
+	}
+	for _, testCase := range testCases {
+		t.Run(testCase.user, func(t *testing.T) {
+			t.Parallel()
+			s := Spec{
+				Version: specs.Version,
+				Root: &specs.Root{
+					Path: td,
+				},
+				Linux: &specs.Linux{},
+			}
+			err := WithUsername(testCase.user)(context.Background(), nil, &c, &s)
+			if err != nil {
+				assert.EqualError(t, err, testCase.err)
+			}
+			assert.Equal(t, testCase.expectedUID, s.Process.User.UID)
+			assert.Equal(t, testCase.expectedGID, s.Process.User.GID)
+		})
+	}
+
+}
+
 // nolint:gosec
 func TestWithAdditionalGIDs(t *testing.T) {
 	t.Parallel()
@@ -54,7 +172,6 @@ sys:x:3:root,bin,adm
 	c := containers.Container{ID: t.Name()}
 
 	testCases := []struct {
-		name     string
 		user     string
 		expected []uint32
 	}{