Make caches singletons

cmd/wire_gen.go

@@ -26,7 +26,7 @@ func CreateServer(musicFolder string) *server.Server {
 
 func CreateScanner(musicFolder string) scanner.Scanner {
 	dataStore := persistence.New()
-	artworkCache := core.NewImageCache()
+	artworkCache := core.GetImageCache()
 	artwork := core.NewArtwork(dataStore, artworkCache)
 	cacheWarmer := core.NewCacheWarmer(artwork)
 	scannerScanner := scanner.New(dataStore, cacheWarmer)
@@ -41,10 +41,10 @@ func CreateAppRouter() *app.Router {
 
 func CreateSubsonicAPIRouter() *subsonic.Router {
 	dataStore := persistence.New()
-	artworkCache := core.NewImageCache()
+	artworkCache := core.GetImageCache()
 	artwork := core.NewArtwork(dataStore, artworkCache)
 	transcoderTranscoder := transcoder.New()
-	transcodingCache := core.NewTranscodingCache()
+	transcodingCache := core.GetTranscodingCache()
 	mediaStreamer := core.NewMediaStreamer(dataStore, transcoderTranscoder, transcodingCache)
 	archiver := core.NewArchiver(dataStore)
 	players := core.NewPlayers(dataStore)

core/artwork.go

@@ -12,6 +12,7 @@ import (
 	"io"
 	"os"
 	"strings"
+	"sync"
 	"time"
 
 	"github.com/deluan/navidrome/core/cache"
@@ -205,15 +206,23 @@ func readFromFile(path string) ([]byte, error) {
 	return buf.Bytes(), nil
 }
 
-func NewImageCache() ArtworkCache {
-	return cache.NewFileCache("Image", conf.Server.ImageCacheSize, consts.ImageCacheDir, consts.DefaultImageCacheMaxItems,
-		func(ctx context.Context, arg cache.Item) (io.Reader, error) {
-			info := arg.(*imageInfo)
-			reader, err := info.a.getArtwork(ctx, info.id, info.path, info.size)
-			if err != nil {
-				log.Error(ctx, "Error loading artwork art", "path", info.path, "size", info.size, err)
-				return nil, err
-			}
-			return reader, nil
-		})
+var (
+	onceImageCache     sync.Once
+	instanceImageCache ArtworkCache
+)
+
+func GetImageCache() ArtworkCache {
+	onceImageCache.Do(func() {
+		instanceImageCache = cache.NewFileCache("Image", conf.Server.ImageCacheSize, consts.ImageCacheDir, consts.DefaultImageCacheMaxItems,
+			func(ctx context.Context, arg cache.Item) (io.Reader, error) {
+				info := arg.(*imageInfo)
+				reader, err := info.a.getArtwork(ctx, info.id, info.path, info.size)
+				if err != nil {
+					log.Error(ctx, "Error loading artwork art", "path", info.path, "size", info.size, err)
+					return nil, err
+				}
+				return reader, nil
+			})
+	})
+	return instanceImageCache
 }

core/artwork_test.go

@@ -5,7 +5,6 @@ import (
 	"context"
 	"image"
 	"io/ioutil"
-	"os"
 
 	"github.com/deluan/navidrome/conf"
 	"github.com/deluan/navidrome/log"
@@ -37,15 +36,11 @@ var _ = Describe("Artwork", func() {
 		BeforeEach(func() {
 			conf.Server.DataFolder, _ = ioutil.TempDir("", "file_caches")
 			conf.Server.ImageCacheSize = "100MB"
-			cache := NewImageCache()
+			cache := GetImageCache()
 			Eventually(func() bool { return cache.Ready() }).Should(BeTrue())
 			artwork = NewArtwork(ds, cache)
 		})
 
-		AfterEach(func() {
-			os.RemoveAll(conf.Server.DataFolder)
-		})
-
 		It("retrieves the external artwork art for an album", func() {
 			buf := new(bytes.Buffer)
 

core/media_streamer.go

@@ -6,6 +6,7 @@ import (
 	"io"
 	"mime"
 	"os"
+	"sync"
 	"time"
 
 	"github.com/deluan/navidrome/conf"
@@ -167,21 +168,29 @@ func selectTranscodingOptions(ctx context.Context, ds model.DataStore, mf *model
 	return
 }
 
-func NewTranscodingCache() TranscodingCache {
-	return cache.NewFileCache("Transcoding", conf.Server.TranscodingCacheSize,
-		consts.TranscodingCacheDir, consts.DefaultTranscodingCacheMaxItems,
-		func(ctx context.Context, arg cache.Item) (io.Reader, error) {
-			job := arg.(*streamJob)
-			t, err := job.ms.ds.Transcoding(ctx).FindByFormat(job.format)
-			if err != nil {
-				log.Error(ctx, "Error loading transcoding command", "format", job.format, err)
-				return nil, os.ErrInvalid
-			}
-			out, err := job.ms.ffm.Start(ctx, t.Command, job.mf.Path, job.bitRate)
-			if err != nil {
-				log.Error(ctx, "Error starting transcoder", "id", job.mf.ID, err)
-				return nil, os.ErrInvalid
-			}
-			return out, nil
-		})
+var (
+	onceTranscodingCache     sync.Once
+	instanceTranscodingCache TranscodingCache
+)
+
+func GetTranscodingCache() TranscodingCache {
+	onceTranscodingCache.Do(func() {
+		instanceTranscodingCache = cache.NewFileCache("Transcoding", conf.Server.TranscodingCacheSize,
+			consts.TranscodingCacheDir, consts.DefaultTranscodingCacheMaxItems,
+			func(ctx context.Context, arg cache.Item) (io.Reader, error) {
+				job := arg.(*streamJob)
+				t, err := job.ms.ds.Transcoding(ctx).FindByFormat(job.format)
+				if err != nil {
+					log.Error(ctx, "Error loading transcoding command", "format", job.format, err)
+					return nil, os.ErrInvalid
+				}
+				out, err := job.ms.ffm.Start(ctx, t.Command, job.mf.Path, job.bitRate)
+				if err != nil {
+					log.Error(ctx, "Error starting transcoder", "id", job.mf.ID, err)
+					return nil, os.ErrInvalid
+				}
+				return out, nil
+			})
+	})
+	return instanceTranscodingCache
 }

core/media_streamer_test.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"io"
 	"io/ioutil"
-	"os"
 	"strings"
 
 	"github.com/deluan/navidrome/conf"
@@ -29,15 +28,11 @@ var _ = Describe("MediaStreamer", func() {
 		ds.MediaFile(ctx).(*tests.MockMediaFile).SetData(model.MediaFiles{
 			{ID: "123", Path: "tests/fixtures/test.mp3", Suffix: "mp3", BitRate: 128, Duration: 257.0},
 		})
-		testCache := NewTranscodingCache()
+		testCache := GetTranscodingCache()
 		Eventually(func() bool { return testCache.Ready() }).Should(BeTrue())
 		streamer = NewMediaStreamer(ds, ffmpeg, testCache)
 	})
 
-	AfterEach(func() {
-		os.RemoveAll(conf.Server.DataFolder)
-	})
-
 	Context("NewStream", func() {
 		It("returns a seekable stream if format is 'raw'", func() {
 			s, err := streamer.NewStream(ctx, "123", "raw", 0)

core/wire_providers.go

@@ -13,8 +13,8 @@ import (
 var Set = wire.NewSet(
 	NewArtwork,
 	NewMediaStreamer,
-	NewTranscodingCache,
-	NewImageCache,
+	GetTranscodingCache,
+	GetImageCache,
 	NewArchiver,
 	NewNowPlayingRepository,
 	NewExternalInfo,