Add number of tracks and discs of an album to API

api/funkwhale_api/music/models.py

@@ -20,6 +20,7 @@ from django.db.models.signals import post_save, pre_save
 from django.dispatch import receiver
 from django.urls import reverse
 from django.utils import timezone
+from django.db.models import Prefetch, Count
 
 from funkwhale_api import musicbrainz
 from funkwhale_api.common import fields
@@ -420,7 +421,13 @@ def import_album(v):
 class TrackQuerySet(common_models.LocalFromFidQuerySet, models.QuerySet):
     def for_nested_serialization(self):
         return self.prefetch_related(
-            "artist", "album__artist", "album__attachment_cover"
+            "artist",
+            Prefetch(
+                "album",
+                queryset=Album.objects.select_related(
+                    "artist", "attachment_cover"
+                ).annotate(_prefetched_tracks_count=Count("tracks")),
+            ),
         )
 
     def annotate_playable_by_actor(self, actor):

api/funkwhale_api/music/serializers.py

@@ -227,6 +227,10 @@ class AlbumSerializer(OptionalDescriptionMixin, serializers.Serializer):
 class TrackAlbumSerializer(serializers.ModelSerializer):
     artist = serializers.SerializerMethodField()
     cover = cover_field
+    tracks_count = serializers.SerializerMethodField()
+
+    def get_tracks_count(self, o):
+        return getattr(o, "_prefetched_tracks_count", len(o.tracks.all()))
 
     class Meta:
         model = models.Album
@@ -240,6 +244,7 @@ class TrackAlbumSerializer(serializers.ModelSerializer):
             "cover",
             "creation_date",
             "is_local",
+            "tracks_count",
         )
 
     def get_artist(self, o):