Reduce number of queries for some playlists operations.

Also allow admins to update/delete playlists from other users in the Subsonic API. Closes #1366

persistence/playlist_repository.go

@@ -105,6 +105,10 @@ func (r *playlistRepository) Put(p *model.Playlist) error {
 }
 
 func (r *playlistRepository) Get(id string) (*model.Playlist, error) {
+	return r.findBy(And{Eq{"id": id}, r.userFilter()}, false)
+}
+
+func (r *playlistRepository) GetWithTracks(id string) (*model.Playlist, error) {
 	return r.findBy(And{Eq{"id": id}, r.userFilter()}, true)
 }
 
@@ -112,10 +116,6 @@ func (r *playlistRepository) FindByPath(path string) (*model.Playlist, error) {
 	return r.findBy(Eq{"path": path}, false)
 }
 
-func (r *playlistRepository) FindByID(id string) (*model.Playlist, error) {
-	return r.findBy(And{Eq{"id": id}, r.userFilter()}, false)
-}
-
 func (r *playlistRepository) findBy(sql Sqlizer, includeTracks bool) (*model.Playlist, error) {
 	sel := r.newSelect().Columns("*").Where(sql)
 	var pls []dbPlaylist

persistence/playlist_repository_test.go

@@ -55,7 +55,7 @@ var _ = Describe("PlaylistRepository", func() {
 			Expect(err).To(MatchError(model.ErrNotFound))
 		})
 		It("returns all tracks", func() {
-			pls, err := repo.Get(plsBest.ID)
+			pls, err := repo.GetWithTracks(plsBest.ID)
 			Expect(err).To(BeNil())
 			Expect(pls.Name).To(Equal(plsBest.Name))
 			Expect(pls.Tracks).To(Equal(model.MediaFiles{
@@ -76,7 +76,7 @@ var _ = Describe("PlaylistRepository", func() {
 		By("adds repeated songs to a playlist and keeps the order")
 		newPls.Tracks = append(newPls.Tracks, model.MediaFile{ID: "1004"})
 		Expect(repo.Put(&newPls)).To(BeNil())
-		saved, _ := repo.Get(newPls.ID)
+		saved, _ := repo.GetWithTracks(newPls.ID)
 		Expect(saved.Tracks).To(HaveLen(3))
 		Expect(saved.Tracks[0].ID).To(Equal("1004"))
 		Expect(saved.Tracks[1].ID).To(Equal("1003"))

persistence/playlist_track_repository.go

@@ -48,8 +48,8 @@ func (r *playlistTrackRepository) Read(id string) (interface{}, error) {
 	return &trk, err
 }
 
-func (r *playlistTrackRepository) ReadAll(options ...rest.QueryOptions) (interface{}, error) {
-	sel := r.newSelect(r.parseRestOptions(options...)).
+func (r *playlistTrackRepository) GetAll(options ...model.QueryOptions) (model.PlaylistTracks, error) {
+	sel := r.newSelect(options...).
 		LeftJoin("annotation on ("+
 			"annotation.item_id = media_file_id"+
 			" AND annotation.item_type = 'media_file'"+
@@ -62,6 +62,10 @@ func (r *playlistTrackRepository) ReadAll(options ...rest.QueryOptions) (interfa
 	return res, err
 }
 
+func (r *playlistTrackRepository) ReadAll(options ...rest.QueryOptions) (interface{}, error) {
+	return r.GetAll(r.parseRestOptions(options...))
+}
+
 func (r *playlistTrackRepository) EntityName() string {
 	return "playlist_tracks"
 }
@@ -211,7 +215,10 @@ func (r *playlistTrackRepository) Delete(id string) error {
 	if err != nil {
 		return err
 	}
-	return r.updateStats()
+
+	// To renumber the playlist
+	_, err = r.Add(nil)
+	return err
 }
 
 func (r *playlistTrackRepository) Reorder(pos int, newPos int) error {
@@ -231,7 +238,7 @@ func (r *playlistTrackRepository) isWritable() bool {
 	if usr.IsAdmin {
 		return true
 	}
-	pls, err := r.playlistRepo.FindByID(r.playlistId)
+	pls, err := r.playlistRepo.Get(r.playlistId)
 	return err == nil && pls.Owner == usr.UserName
 }