Added SongsByFolder filter

Signed-off-by: Patrik Wallström <pawal@amplitut.de>

server/subsonic/filter/filter_suite_test.go

@@ -0,0 +1,17 @@
+package filter_test
+
+import (
+	"testing"
+
+	"github.com/navidrome/navidrome/log"
+	"github.com/navidrome/navidrome/tests"
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+func TestFilter(t *testing.T) {
+	tests.Init(t, false)
+	log.SetLevel(log.LevelFatal)
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "Subsonic Filter Suite")
+}

server/subsonic/filter/filters.go

@@ -90,6 +90,13 @@ func SongsByAlbum(albumId string) Options {
 	})
 }
 
+func SongsByFolder(folderID string) Options {
+	return addDefaultFilters(Options{
+		Filters: Eq{"folder_id": folderID},
+		Sort:    "path",
+	})
+}
+
 func SongsByRandom(genre string, fromYear, toYear int) Options {
 	options := Options{
 		Sort: "random",

server/subsonic/filter/filters_test.go

@@ -0,0 +1,32 @@
+package filter_test
+
+import (
+	sq "github.com/Masterminds/squirrel"
+	. "github.com/navidrome/navidrome/server/subsonic/filter"
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("SongsByFolder", func() {
+	It("sets sort to path", func() {
+		opts := SongsByFolder("folder-1")
+		Expect(opts.Sort).To(Equal("path"))
+	})
+
+	It("filters by the given folder ID", func() {
+		opts := SongsByFolder("folder-1")
+		Expect(opts.Filters).To(Equal(sq.And{sq.Eq{"missing": false}, sq.Eq{"folder_id": "folder-1"}}))
+	})
+
+	It("uses a different folder ID per call", func() {
+		opts := SongsByFolder("folder-2")
+		Expect(opts.Filters).To(Equal(sq.And{sq.Eq{"missing": false}, sq.Eq{"folder_id": "folder-2"}}))
+	})
+
+	It("excludes missing files via default filter", func() {
+		opts := SongsByFolder("any-folder")
+		filters, ok := opts.Filters.(sq.And)
+		Expect(ok).To(BeTrue())
+		Expect(filters).To(ContainElement(sq.Eq{"missing": false}))
+	})
+})