Created dedicated artwork readers

core/artwork/reader_emptyid.go

@@ -0,0 +1,35 @@
+package artwork
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"time"
+
+	"github.com/navidrome/navidrome/conf"
+	"github.com/navidrome/navidrome/model"
+)
+
+type emptyIDReader struct {
+	artID model.ArtworkID
+}
+
+func newEmptyIDReader(_ context.Context, artID model.ArtworkID) (*emptyIDReader, error) {
+	a := &emptyIDReader{
+		artID: artID,
+	}
+	return a, nil
+}
+
+func (a *emptyIDReader) LastUpdated() time.Time {
+	return time.Now() // Basically make it non-cacheable
+}
+
+func (a *emptyIDReader) Key() string {
+	return fmt.Sprintf("0.%d.0.%d", a.LastUpdated().UnixMilli(), conf.Server.CoverJpegQuality)
+}
+
+func (a *emptyIDReader) Reader(ctx context.Context) (io.ReadCloser, string, error) {
+	r, source := extractImage(ctx, a.artID, fromPlaceholder())
+	return r, source, nil
+}