See #170: filtering subscribed channels in API

api/funkwhale_api/audio/filters.py

+from django.db.models import Q
+
 import django_filters
 
 from funkwhale_api.common import fields
@@ -23,12 +25,30 @@ class ChannelFilter(moderation_filters.HiddenContentFilterSet):
     )
     tag = TAG_FILTER
     scope = common_filters.ActorScopeFilter(actor_field="attributed_to", distinct=True)
+    subscribed = django_filters.BooleanFilter(
+        field_name="_", method="filter_subscribed"
+    )
 
     class Meta:
         model = models.Channel
-        fields = ["q", "scope", "tag"]
+        fields = ["q", "scope", "tag", "subscribed"]
         hidden_content_fields_mapping = moderation_filters.USER_FILTER_CONFIG["CHANNEL"]
 
+    def filter_subscribed(self, queryset, name, value):
+        if not self.request.user.is_authenticated:
+            return queryset.none()
+
+        emitted_follows = self.request.user.actor.emitted_follows.exclude(
+            target__channel__isnull=True
+        )
+
+        query = Q(actor__in=emitted_follows.values_list("target", flat=True))
+
+        if value is True:
+            return queryset.filter(query)
+        else:
+            return queryset.exclude(query)
+
 
 class IncludeChannelsFilterSet(django_filters.FilterSet):
     """

api/tests/audio/test_filters.py

+from funkwhale_api.audio import filters
+from funkwhale_api.audio import models
+
+
+def test_channel_filter_subscribed_true(factories, mocker, queryset_equal_list):
+    user = factories["users.User"](with_actor=True)
+    channel = factories["audio.Channel"]()
+    other_channel = factories["audio.Channel"]()
+    factories["audio.Subscription"](target=channel.actor, actor=user.actor)
+    factories["audio.Subscription"](target=other_channel.actor)
+
+    qs = models.Channel.objects.all()
+    filterset = filters.ChannelFilter(
+        {"subscribed": "true"}, request=mocker.Mock(user=user), queryset=qs
+    )
+
+    assert filterset.qs == [channel]
+
+
+def test_channel_filter_subscribed_false(factories, mocker, queryset_equal_list):
+    user = factories["users.User"](with_actor=True)
+    channel = factories["audio.Channel"]()
+    other_channel = factories["audio.Channel"]()
+    factories["audio.Subscription"](target=channel.actor, actor=user.actor)
+    factories["audio.Subscription"](target=other_channel.actor)
+
+    qs = models.Channel.objects.all()
+    filterset = filters.ChannelFilter(
+        {"subscribed": "false"}, request=mocker.Mock(user=user), queryset=qs
+    )
+
+    assert filterset.qs == [other_channel]