Backups: Improved saving of photo and album YAML files #4243

Signed-off-by: Michael Mayer <michael@photoprism.app>

internal/api/albums.go

@@ -2,7 +2,6 @@ package api
 
 import (
 	"net/http"
-	"path/filepath"
 	"sync"
 
 	"github.com/gin-gonic/gin"
@@ -20,23 +19,17 @@ import (
 
 var albumMutex = sync.Mutex{}
 
-// SaveAlbumYaml backs up the album metadata in YAML files.
+// SaveAlbumYaml saves the album metadata to a YAML backup file.
 func SaveAlbumYaml(a entity.Album) {
 	c := get.Config()
 
-	// Check if album YAML backups are enabled.
+	// Check if saving YAML backup files is enabled.
 	if !c.BackupAlbums() {
 		return
 	}
 
-	// Create or update album backup file.
-	fileName := a.YamlFileName(c.BackupAlbumsPath())
-
-	if err := a.SaveAsYaml(fileName); err != nil {
-		log.Errorf("album: %s (save as yaml)", err)
-	} else {
-		log.Debugf("album: updated backup file %s", clean.Log(filepath.Base(fileName)))
-	}
+	// Write album metadata to YAML backup file.
+	_ = a.SaveBackupYaml(c.BackupAlbumsPath())
 }
 
 // GetAlbum returns album details as JSON.

internal/api/photos.go

@@ -2,7 +2,6 @@ package api
 
 import (
 	"net/http"
-	"path/filepath"
 
 	"github.com/gin-gonic/gin"
 
@@ -18,7 +17,7 @@ import (
 	"github.com/photoprism/photoprism/pkg/i18n"
 )
 
-// SaveSidecarYaml saves picture metadata as YAML file.
+// SaveSidecarYaml saves the photo metadata to a YAML sidecar file.
 func SaveSidecarYaml(p *entity.Photo) {
 	if p == nil {
 		log.Debugf("api: photo is nil (update yaml)")
@@ -27,19 +26,13 @@ func SaveSidecarYaml(p *entity.Photo) {
 
 	c := get.Config()
 
-	// Check if creating and updating YAML sidecar files is enabled.
+	// Check if saving YAML sidecar files is enabled.
 	if !c.SidecarYaml() {
 		return
 	}
 
-	// Create or update metadata export in YAML sidecar file.
-	fileName := p.YamlFileName(c.OriginalsPath(), c.SidecarPath())
-
-	if err := p.SaveAsYaml(fileName); err != nil {
-		log.Errorf("photo: %s (save as yaml)", err)
-	} else {
-		log.Debugf("photo: updated sidecar file %s", clean.Log(filepath.Join(p.PhotoPath, p.PhotoName)+fs.ExtYAML))
-	}
+	// Write photo metadata to YAML sidecar file.
+	_ = p.SaveSidecarYaml(c.OriginalsPath(), c.SidecarPath())
 }
 
 // GetPhoto returns photo details as JSON.

internal/entity/album_yaml.go

@@ -1,6 +1,7 @@
 package entity
 
 import (
+	"fmt"
 	"os"
 	"path/filepath"
 	"sync"
@@ -8,6 +9,7 @@ import (
 
 	"gopkg.in/yaml.v2"
 
+	"github.com/photoprism/photoprism/pkg/clean"
 	"github.com/photoprism/photoprism/pkg/fs"
 )
 
@@ -26,8 +28,16 @@ func (m *Album) Yaml() (out []byte, err error) {
 	return yaml.Marshal(m)
 }
 
-// SaveAsYaml saves album data as YAML file.
+// SaveAsYaml writes the album metadata to a YAML backup file with the specified filename.
 func (m *Album) SaveAsYaml(fileName string) error {
+	if m == nil {
+		return fmt.Errorf("album entity is nil - you may have found a bug")
+	} else if m.AlbumUID == "" {
+		return fmt.Errorf("album uid is empty")
+	} else if fileName == "" {
+		return fmt.Errorf("yaml filname is empty")
+	}
+
 	data, err := m.Yaml()
 
 	if err != nil {
@@ -50,22 +60,66 @@ func (m *Album) SaveAsYaml(fileName string) error {
 	return nil
 }
 
-// LoadFromYaml photo data from a YAML file.
+// YamlFileName returns the absolute file path for the YAML backup file.
+func (m *Album) YamlFileName(backupPath string) (absolute, relative string, err error) {
+	if m == nil {
+		return "", "", fmt.Errorf("album entity is nil - you may have found a bug")
+	} else if m.AlbumUID == "" {
+		return "", "", fmt.Errorf("album uid is empty")
+	}
+
+	relative = filepath.Join(m.AlbumType, m.AlbumUID+fs.ExtYAML)
+
+	if backupPath == "" {
+		return "", relative, fmt.Errorf("backup path is empty")
+	}
+
+	absolute = filepath.Join(backupPath, relative)
+
+	return absolute, relative, err
+}
+
+// SaveBackupYaml writes the album metadata to a YAML backup file based on the specified storage paths.
+func (m *Album) SaveBackupYaml(backupPath string) error {
+	if m == nil {
+		return fmt.Errorf("album entity is nil - you may have found a bug")
+	} else if m.AlbumUID == "" {
+		return fmt.Errorf("album uid is empty")
+	} else if backupPath == "" {
+		return fmt.Errorf("backup path is empty")
+	}
+
+	// Write metadata to YAML backup file.
+	if fileName, relName, err := m.YamlFileName(backupPath); err != nil {
+		log.Warnf("album: %s (save %s)", err, clean.Log(relName))
+		return err
+	} else if err = m.SaveAsYaml(fileName); err != nil {
+		log.Warnf("album: %s (save %s)", err, clean.Log(relName))
+		return err
+	} else {
+		log.Debugf("album: saved backup file %s", clean.Log(relName))
+	}
+
+	return nil
+}
+
+// LoadFromYaml restores the album metadata from a YAML backup file.
 func (m *Album) LoadFromYaml(fileName string) error {
+	if m == nil {
+		return fmt.Errorf("album entity is nil - you may have found a bug")
+	} else if fileName == "" {
+		return fmt.Errorf("yaml filename is empty")
+	}
+
 	data, err := os.ReadFile(fileName)
 
 	if err != nil {
 		return err
 	}
 
-	if err := yaml.Unmarshal(data, m); err != nil {
+	if err = yaml.Unmarshal(data, m); err != nil {
 		return err
 	}
 
 	return nil
 }
-
-// YamlFileName returns the YAML file name.
-func (m *Album) YamlFileName(albumsPath string) string {
-	return filepath.Join(albumsPath, m.AlbumType, m.AlbumUID+fs.ExtYAML)
-}

internal/entity/album_yaml_test.go

@@ -2,9 +2,12 @@ package entity
 
 import (
 	"os"
+	"strings"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+
+	"github.com/photoprism/photoprism/pkg/fs"
 )
 
 func TestAlbum_Yaml(t *testing.T) {
@@ -45,7 +48,7 @@ func TestAlbum_Yaml(t *testing.T) {
 }
 
 func TestAlbum_SaveAsYaml(t *testing.T) {
-	t.Run("berlin-2019", func(t *testing.T) {
+	t.Run("Success", func(t *testing.T) {
 		m := AlbumFixtures.Get("berlin-2019")
 
 		if found := m.Find(); found == nil {
@@ -54,18 +57,64 @@ func TestAlbum_SaveAsYaml(t *testing.T) {
 			m = *found
 		}
 
-		fileName := m.YamlFileName("testdata")
+		backupPath := fs.Abs("testdata/TestAlbum_SaveAsYaml")
 
-		if err := m.SaveAsYaml(fileName); err != nil {
+		fileName, relName, err := m.YamlFileName(backupPath)
+
+		assert.NoError(t, err)
+		assert.True(t, strings.HasSuffix(fileName, "internal/entity/testdata/TestAlbum_SaveAsYaml/album/as6sg6bxpogaaba9.yml"))
+		assert.Equal(t, "album/as6sg6bxpogaaba9.yml", relName)
+
+		if err = m.SaveAsYaml(fileName); err != nil {
 			t.Fatal(err)
+			return
 		}
 
-		if err := m.LoadFromYaml(fileName); err != nil {
-			t.Fatal(err)
+		if err = m.LoadFromYaml(fileName); err != nil {
+			t.Error(err)
 		}
 
-		if err := os.Remove(fileName); err != nil {
+		if err = os.RemoveAll(backupPath); err != nil {
+			t.Error(err)
+		}
+	})
+}
+
+func TestAlbum_YamlFileName(t *testing.T) {
+	t.Run("Success", func(t *testing.T) {
+		m := AlbumFixtures.Get("berlin-2019")
+
+		if found := m.Find(); found == nil {
+			t.Fatal("should find album")
+		} else {
+			m = *found
+		}
+
+		fileName, relName, err := m.YamlFileName("/foo/bar")
+
+		assert.NoError(t, err)
+		assert.Equal(t, "/foo/bar/album/as6sg6bxpogaaba9.yml", fileName)
+		assert.Equal(t, "album/as6sg6bxpogaaba9.yml", relName)
+	})
+}
+
+func TestAlbum_SaveBackupYaml(t *testing.T) {
+	t.Run("Success", func(t *testing.T) {
+		m := AlbumFixtures.Get("berlin-2019")
+
+		backupPath := fs.Abs("testdata/TestAlbum_SaveBackupYaml")
+
+		if err := fs.MkdirAll(backupPath); err != nil {
 			t.Fatal(err)
+			return
+		}
+
+		if err := m.SaveBackupYaml(backupPath); err != nil {
+			t.Error(err)
+		}
+
+		if err := os.RemoveAll(backupPath); err != nil {
+			t.Error(err)
 		}
 	})
 }
@@ -111,19 +160,3 @@ func TestAlbum_LoadFromYaml(t *testing.T) {
 		}
 	})
 }
-
-func TestAlbum_YamlFileName(t *testing.T) {
-	t.Run("berlin-2019", func(t *testing.T) {
-		m := AlbumFixtures.Get("berlin-2019")
-
-		if found := m.Find(); found == nil {
-			t.Fatal("should find album")
-		} else {
-			m = *found
-		}
-
-		fileName := m.YamlFileName("/foo/bar")
-
-		assert.Equal(t, "/foo/bar/album/as6sg6bxpogaaba9.yml", fileName)
-	})
-}

internal/entity/auth_client.go

@@ -271,7 +271,7 @@ func (m *Client) Save() error {
 // Delete marks the entity as deleted.
 func (m *Client) Delete() (err error) {
 	if m.ClientUID == "" {
-		return fmt.Errorf("client uid is missing")
+		return fmt.Errorf("client uid is empty")
 	}
 
 	if _, err = m.DeleteSessions(); err != nil {
@@ -286,7 +286,7 @@ func (m *Client) Delete() (err error) {
 // DeleteSessions deletes all sessions that belong to this client.
 func (m *Client) DeleteSessions() (deleted int, err error) {
 	if m.ClientUID == "" {
-		return 0, fmt.Errorf("client uid is missing")
+		return 0, fmt.Errorf("client uid is empty")
 	}
 
 	if deleted = DeleteClientSessions(m, "", 0); deleted > 0 {

internal/entity/photo_yaml.go

@@ -1,6 +1,7 @@
 package entity
 
 import (
+	"fmt"
 	"os"
 	"path/filepath"
 	"sync"
@@ -8,6 +9,7 @@ import (
 
 	"gopkg.in/yaml.v2"
 
+	"github.com/photoprism/photoprism/pkg/clean"
 	"github.com/photoprism/photoprism/pkg/fs"
 )
 
@@ -30,8 +32,16 @@ func (m *Photo) Yaml() ([]byte, error) {
 	return out, err
 }
 
-// SaveAsYaml saves photo data as YAML file.
+// SaveAsYaml writes the photo metadata to a YAML sidecar file with the specified filename.
 func (m *Photo) SaveAsYaml(fileName string) error {
+	if m == nil {
+		return fmt.Errorf("photo entity is nil - you may have found a bug")
+	} else if fileName == "" {
+		return fmt.Errorf("yaml filename is empty")
+	} else if m.PhotoUID == "" {
+		return fmt.Errorf("photo uid is empty")
+	}
+
 	data, err := m.Yaml()
 
 	if err != nil {
@@ -54,22 +64,55 @@ func (m *Photo) SaveAsYaml(fileName string) error {
 	return nil
 }
 
-// LoadFromYaml photo data from a YAML file.
+// YamlFileName returns both the absolute file path and the relative name for the YAML sidecar file, e.g. for logging.
+func (m *Photo) YamlFileName(originalsPath, sidecarPath string) (absolute, relative string, err error) {
+	absolute, err = fs.FileName(filepath.Join(originalsPath, m.PhotoPath, m.PhotoName), sidecarPath, originalsPath, fs.ExtYAML)
+	relative = filepath.Join(m.PhotoPath, m.PhotoName) + fs.ExtYAML
+
+	return absolute, relative, err
+}
+
+// SaveSidecarYaml writes the photo metadata to a YAML sidecar file based on the specified storage paths.
+func (m *Photo) SaveSidecarYaml(originalsPath, sidecarPath string) error {
+	if m == nil {
+		return fmt.Errorf("photo entity is nil - you may have found a bug")
+	} else if m.PhotoName == "" {
+		return fmt.Errorf("photo name is empty")
+	} else if m.PhotoUID == "" {
+		return fmt.Errorf("photo uid is empty")
+	}
+
+	// Write metadata to YAML sidecar file.
+	if fileName, relName, err := m.YamlFileName(originalsPath, sidecarPath); err != nil {
+		log.Warnf("photo: %s (save %s)", err, clean.Log(relName))
+		return err
+	} else if err = m.SaveAsYaml(fileName); err != nil {
+		log.Warnf("photo: %s (save %s)", err, clean.Log(relName))
+		return err
+	} else {
+		log.Infof("photo: saved sidecar file %s", clean.Log(relName))
+	}
+
+	return nil
+}
+
+// LoadFromYaml restores the photo metadata from a YAML sidecar file.
 func (m *Photo) LoadFromYaml(fileName string) error {
+	if m == nil {
+		return fmt.Errorf("photo entity is nil - you may have found a bug")
+	} else if fileName == "" {
+		return fmt.Errorf("yaml filename is empty")
+	}
+
 	data, err := os.ReadFile(fileName)
 
 	if err != nil {
 		return err
 	}
 
-	if err := yaml.Unmarshal(data, m); err != nil {
+	if err = yaml.Unmarshal(data, m); err != nil {
 		return err
 	}
 
 	return nil
 }
-
-// YamlFileName returns the YAML file name.
-func (m *Photo) YamlFileName(originalsPath, sidecarPath string) string {
-	return fs.FileName(filepath.Join(originalsPath, m.PhotoPath, m.PhotoName), sidecarPath, originalsPath, fs.ExtYAML)
-}

internal/entity/photo_yaml_test.go

@@ -6,10 +6,12 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+
+	"github.com/photoprism/photoprism/pkg/fs"
 )
 
 func TestPhoto_Yaml(t *testing.T) {
-	t.Run("create from fixture", func(t *testing.T) {
+	t.Run("Success", func(t *testing.T) {
 		m := PhotoFixtures.Get("Photo01")
 		m.PreloadFiles()
 		result, err := m.Yaml()
@@ -23,7 +25,7 @@ func TestPhoto_Yaml(t *testing.T) {
 }
 
 func TestPhoto_SaveAsYaml(t *testing.T) {
-	t.Run("create from fixture", func(t *testing.T) {
+	t.Run("Success", func(t *testing.T) {
 		m := PhotoFixtures.Get("Photo01")
 		m.PreloadFiles()
 
@@ -44,13 +46,48 @@ func TestPhoto_SaveAsYaml(t *testing.T) {
 }
 
 func TestPhoto_YamlFileName(t *testing.T) {
-	t.Run("create from fixture", func(t *testing.T) {
+	t.Run("Success", func(t *testing.T) {
 		m := PhotoFixtures.Get("Photo01")
 		m.PreloadFiles()
-		assert.Equal(t, "xxx/2790/02/yyy/Photo01.yml", m.YamlFileName("xxx", "yyy"))
+		fileName, relative, err := m.YamlFileName("xxx", "yyy")
+		assert.NoError(t, err)
+		assert.Equal(t, "xxx/2790/02/yyy/Photo01.yml", fileName)
+		assert.Equal(t, "2790/02/Photo01.yml", relative)
 
 		if err := os.RemoveAll("xxx"); err != nil {
 			t.Fatal(err)
 		}
 	})
 }
+
+func TestPhoto_SaveSidecarYaml(t *testing.T) {
+	t.Run("Success", func(t *testing.T) {
+		m := PhotoFixtures.Get("Photo01")
+		m.PreloadFiles()
+
+		basePath := fs.Abs("testdata/yaml")
+		originalsPath := filepath.Join(basePath, "originals")
+		sidecarPath := filepath.Join(basePath, "sidecar")
+
+		t.Logf("originalsPath: %s", originalsPath)
+		t.Logf("sidecarPath: %s", sidecarPath)
+
+		if err := fs.MkdirAll(originalsPath); err != nil {
+			t.Fatal(err)
+			return
+		}
+
+		if err := fs.MkdirAll(sidecarPath); err != nil {
+			t.Fatal(err)
+			return
+		}
+
+		if err := m.SaveSidecarYaml(originalsPath, sidecarPath); err != nil {
+			t.Error(err)
+		}
+
+		if err := os.RemoveAll(basePath); err != nil {
+			t.Error(err)
+		}
+	})
+}

internal/photoprism/backup_albums.go

@@ -1,7 +1,6 @@
 package photoprism
 
 import (
-	"path/filepath"
 	"sync"
 	"time"
 
@@ -38,22 +37,23 @@ func BackupAlbums(backupPath string, force bool) (count int, err error) {
 		latest = backupAlbumsLatest
 	}
 
+	// Save albums to YAML backup files.
 	for _, a := range albums {
-		if !force && a.UpdatedAt.Before(backupAlbumsLatest) {
+		// Skip albums that have already been saved to YAML backup files.
+		if !force && !backupAlbumsLatest.IsZero() && !a.UpdatedAt.IsZero() &&
+			a.UpdatedAt.Before(backupAlbumsLatest) {
 			continue
 		}
 
+		// Remember most recent date.
 		if a.UpdatedAt.After(latest) {
 			latest = a.UpdatedAt
 		}
 
-		fileName := a.YamlFileName(backupPath)
-
-		if saveErr := a.SaveAsYaml(fileName); saveErr != nil {
-			log.Errorf("album: %s (save as yaml)", saveErr)
+		// Write album metadata to YAML backup file.
+		if saveErr := a.SaveBackupYaml(backupPath); saveErr != nil {
 			err = saveErr
 		} else {
-			log.Tracef("album: updated backup file %s", clean.Log(filepath.Base(fileName)))
 			count++
 		}
 	}

internal/photoprism/convert_image.go

@@ -49,8 +49,8 @@ func (c *Convert) ToImage(f *MediaFile, force bool) (*MediaFile, error) {
 	// Replace existing sidecar if "force" is true.
 	if err == nil && mediaFile.IsPreviewImage() {
 		if force && mediaFile.InSidecar() {
-			if err := mediaFile.Remove(); err != nil {
-				return mediaFile, fmt.Errorf("convert: failed removing %s (%s)", clean.Log(mediaFile.RootRelName()), err)
+			if removeErr := mediaFile.Remove(); removeErr != nil {
+				return mediaFile, fmt.Errorf("convert: failed removing %s (%s)", clean.Log(mediaFile.RootRelName()), removeErr)
 			} else {
 				log.Infof("convert: replacing %s", clean.Log(mediaFile.RootRelName()))
 			}
@@ -61,9 +61,9 @@ func (c *Convert) ToImage(f *MediaFile, force bool) (*MediaFile, error) {
 		if !c.conf.VectorEnabled() {
 			return nil, fmt.Errorf("convert: vector graphics support disabled (%s)", clean.Log(f.RootRelName()))
 		}
-		imageName = fs.FileName(f.FileName(), c.conf.SidecarPath(), c.conf.OriginalsPath(), fs.ExtPNG)
+		imageName, _ = fs.FileName(f.FileName(), c.conf.SidecarPath(), c.conf.OriginalsPath(), fs.ExtPNG)
 	} else {
-		imageName = fs.FileName(f.FileName(), c.conf.SidecarPath(), c.conf.OriginalsPath(), fs.ExtJPEG)
+		imageName, _ = fs.FileName(f.FileName(), c.conf.SidecarPath(), c.conf.OriginalsPath(), fs.ExtJPEG)
 	}
 
 	if !c.conf.SidecarWritable() {

internal/photoprism/convert_video_avc.go

@@ -61,14 +61,14 @@ func (c *Convert) ToAvc(f *MediaFile, encoder ffmpeg.AvcEncoder, noMutex, force
 
 	// Use .mp4 file extension for animated images and .avi for videos.
 	if f.IsAnimatedImage() {
-		avcName = fs.FileName(f.FileName(), c.conf.SidecarPath(), c.conf.OriginalsPath(), fs.ExtMP4)
+		avcName, _ = fs.FileName(f.FileName(), c.conf.SidecarPath(), c.conf.OriginalsPath(), fs.ExtMP4)
 	} else {
-		avcName = fs.FileName(f.FileName(), c.conf.SidecarPath(), c.conf.OriginalsPath(), fs.ExtAVC)
+		avcName, _ = fs.FileName(f.FileName(), c.conf.SidecarPath(), c.conf.OriginalsPath(), fs.ExtAVC)
 	}
 
 	cmd, useMutex, err := c.AvcConvertCommand(f, avcName, encoder)
 
-	// Failed?
+	// Return if an error occurred.
 	if err != nil {
 		log.Error(err)
 		return nil, err

internal/photoprism/delete.go

@@ -16,7 +16,11 @@ func DeletePhoto(p *entity.Photo, mediaFiles bool, originals bool) (numFiles int
 		return 0, errors.New("photo is nil")
 	}
 
-	yamlFileName := p.YamlFileName(Config().OriginalsPath(), Config().SidecarPath())
+	yamlFileName, yamlRelName, err := p.YamlFileName(Config().OriginalsPath(), Config().SidecarPath())
+
+	if err != nil {
+		log.Warnf("photo: %s (delete %s)", err, clean.Log(yamlRelName))
+	}
 
 	// Permanently remove photo from index.
 	files, err := p.DeletePermanently()
@@ -33,10 +37,10 @@ func DeletePhoto(p *entity.Photo, mediaFiles bool, originals bool) (numFiles int
 	if !fs.FileExists(yamlFileName) {
 		return numFiles, nil
 	} else if err := os.Remove(yamlFileName); err != nil {
-		log.Warnf("files: failed deleting sidecar %s", clean.Log(filepath.Base(yamlFileName)))
+		log.Warnf("photo: failed deleting sidecar file %s", clean.Log(yamlRelName))
 	} else {
 		numFiles++
-		log.Infof("files: deleted sidecar %s", clean.Log(filepath.Base(yamlFileName)))
+		log.Infof("photo: deleted sidecar file %s", clean.Log(yamlRelName))
 	}
 
 	return numFiles, nil

internal/photoprism/index.go

@@ -222,7 +222,7 @@ func (ind *Index) Start(o IndexOptions) (found fs.Done, updated int) {
 			// Skip files if the filename extension does not match their mime type,
 			// see https://github.com/photoprism/photoprism/issues/3518 for details.
 			if typeErr := mf.CheckType(); typeErr != nil {
-				log.Errorf("index: skipped %s due to %s", clean.Log(mf.RootRelName()), typeErr)
+				log.Warnf("index: skipped %s due to %s", clean.Log(mf.RootRelName()), typeErr)
 				return nil
 			}
 

internal/photoprism/index_mediafile.go

@@ -994,14 +994,8 @@ func (ind *Index) UserMediaFile(m *MediaFile, o IndexOptions, originalName, phot
 
 	// Create backup of picture metadata in sidecar YAML file.
 	if file.FilePrimary && Config().SidecarYaml() {
-		// Get YAML file name.
-		yamlFile := photo.YamlFileName(Config().OriginalsPath(), Config().SidecarPath())
-
-		// Save backup to file.
-		if err = photo.SaveAsYaml(yamlFile); err != nil {
-			log.Errorf("index: %s in %s (save as yaml)", err.Error(), logName)
-		} else {
-			log.Debugf("index: updated sidecar file %s", clean.Log(filepath.Join(photo.PhotoPath, photo.PhotoName)+fs.ExtYAML))
+		if err = photo.SaveSidecarYaml(Config().OriginalsPath(), Config().SidecarPath()); err != nil {
+			log.Errorf("index: %s in %s (save as yaml)", err, logName)
 		}
 	}
 

pkg/fs/name.go

@@ -7,8 +7,14 @@ import (
 	"strings"
 )
 
-// FileName returns the relative filename with the same base and a given extension in a directory.
-func FileName(fileName, dirName, baseDir, fileExt string) string {
+// FileName returns the file path for a sidecar file with the specified extension.
+func FileName(fileName, dirName, baseDir, fileExt string) (string, error) {
+	if fileName == "" {
+		return "", fmt.Errorf("file name is empty")
+	} else if fileExt == "" {
+		return "", fmt.Errorf("file extension is empty")
+	}
+
 	dir := filepath.Dir(fileName)
 
 	if dirName == "" || dirName == "." {
@@ -21,14 +27,15 @@ func FileName(fileName, dirName, baseDir, fileExt string) string {
 		}
 	}
 
+	// Create parent directories if they do not exist yet.
 	if err := MkdirAll(dirName); err != nil {
-		fmt.Println(err.Error())
-		return ""
+		return "", err
 	}
 
+	// Compose and return file path.
 	result := filepath.Join(dirName, filepath.Base(fileName)) + fileExt
 
-	return result
+	return result, nil
 }
 
 // RelName returns the file name relative to a directory.
@@ -41,11 +48,11 @@ func RelName(fileName, dir string) string {
 		return fileName
 	}
 
-	if index := strings.Index(fileName, dir); index == 0 {
-		if index := strings.LastIndex(dir, string(os.PathSeparator)); index == len(dir)-1 {
+	if i := strings.Index(fileName, dir); i == 0 {
+		if i = strings.LastIndex(dir, string(os.PathSeparator)); i == len(dir)-1 {
 			pos := len(dir)
 			return fileName[pos:]
-		} else if index := strings.LastIndex(dir, string(os.PathSeparator)); index != len(dir) {
+		} else if i = strings.LastIndex(dir, string(os.PathSeparator)); i != len(dir) {
 			pos := len(dir) + 1
 			return fileName[pos:]
 		}

pkg/fs/name_test.go

@@ -34,36 +34,29 @@ func TestRelName(t *testing.T) {
 
 func TestFileName(t *testing.T) {
 	t.Run("Test copy 3.jpg", func(t *testing.T) {
-		result := FileName("testdata/Test (4).jpg", ".photoprism", Abs("testdata"), ".xmp")
-
+		result, err := FileName("testdata/Test (4).jpg", ".photoprism", Abs("testdata"), ".xmp")
+		assert.NoError(t, err)
 		assert.Equal(t, "testdata/.photoprism/Test (4).jpg.xmp", result)
 	})
-
 	t.Run("Test (3).jpg", func(t *testing.T) {
-		result := FileName("testdata/Test (4).jpg", ".photoprism", Abs("testdata"), ".xmp")
-
+		result, err := FileName("testdata/Test (4).jpg", ".photoprism", Abs("testdata"), ".xmp")
+		assert.NoError(t, err)
 		assert.Equal(t, "testdata/.photoprism/Test (4).jpg.xmp", result)
 	})
-
 	t.Run("FOO.XMP", func(t *testing.T) {
-		result := FileName("testdata/FOO.XMP", ".photoprism/sub", Abs("testdata"), ".jpeg")
-
+		result, err := FileName("testdata/FOO.XMP", ".photoprism/sub", Abs("testdata"), ".jpeg")
+		assert.NoError(t, err)
 		assert.Equal(t, "testdata/.photoprism/sub/FOO.XMP.jpeg", result)
 	})
-
 	t.Run("Test copy 3.jpg", func(t *testing.T) {
 		tempDir := filepath.Join(os.TempDir(), PPHiddenPathname)
-
-		// t.Logf("TEMP DIR, ABS NAME: %s, %s", tempDir, Abs("testdata/Test (4).jpg"))
-
-		result := FileName(Abs("testdata/Test (4).jpg"), tempDir, Abs("testdata"), ".xmp")
-
+		result, err := FileName(Abs("testdata/Test (4).jpg"), tempDir, Abs("testdata"), ".xmp")
+		assert.NoError(t, err)
 		assert.Equal(t, tempDir+"/Test (4).jpg.xmp", result)
 	})
-
 	t.Run("empty dir", func(t *testing.T) {
-		result := FileName("testdata/FOO.XMP", "", Abs("testdata"), ".jpeg")
-
+		result, err := FileName("testdata/FOO.XMP", "", Abs("testdata"), ".jpeg")
+		assert.NoError(t, err)
 		assert.Equal(t, "testdata/FOO.XMP.jpeg", result)
 	})
 }
@@ -75,7 +68,6 @@ func TestFileNameHidden(t *testing.T) {
 	t.Run("Dot", func(t *testing.T) {
 		assert.True(t, FileNameHidden("/some/.folder"))
 	})
-
 	t.Run("Dots", func(t *testing.T) {
 		assert.False(t, FileNameHidden("/some/image.jpg."))
 		assert.False(t, FileNameHidden("./.some/foo"))