Add familiar followers endpoint

api/schemas.py

@@ -165,3 +165,8 @@ class Relationship(Schema):
 class Context(Schema):
     ancestors: list[Status]
     descendants: list[Status]
+
+
+class FamiliarFollowers(Schema):
+    id: str
+    accounts: list[Account]

api/views/accounts.py

@@ -100,3 +100,30 @@ def account_unfollow(request, id: str):
     service = IdentityService(identity)
     service.unfollow_from(request.identity)
     return service.mastodon_json_relationship(request.identity)
+
+
+@api_router.get(
+    "/v1/accounts/familiar_followers", response=list[schemas.FamiliarFollowers]
+)
+@identity_required
+def familiar_followers(request):
+    """
+    Returns people you follow that also follow given account IDs
+    """
+    ids = request.GET.getlist("id[]")
+    result = []
+    for id in ids:
+        target_identity = get_object_or_404(Identity, pk=id)
+        result.append(
+            {
+                "id": id,
+                "accounts": [
+                    identity.to_mastodon_json()
+                    for identity in Identity.objects.filter(
+                        inbound_follows__source=request.identity,
+                        outbound_follows__target=target_identity,
+                    )[:20]
+                ],
+            }
+        )
+    return result