Participation: Setting recipients will always add the owner.

docs/api/pleroma_api.md

@@ -346,5 +346,5 @@ The status posting endpoint takes an additional parameter, `in_reply_to_conversa
 * Method `PATCH`
 * Authentication: required
 * Params:
-    * `recipients`: A list of ids of users that should receive posts to this conversation.
+    * `recipients`: A list of ids of users that should receive posts to this conversation. This will replace the current list of recipients, so submit the full list. The owner of owner of the conversation will always be part of the set of recipients, though.
 * Response: JSON, statuses (200 - healthy, 503 unhealthy)

lib/pleroma/conversation/participation.ex

@@ -101,6 +101,10 @@ defmodule Pleroma.Conversation.Participation do
   end
 
   def set_recipients(participation, user_ids) do
+    user_ids =
+      [participation.user_id | user_ids]
+      |> Enum.uniq()
+
     Repo.transaction(fn ->
       query =
         from(r in RecipientShip,
@@ -118,5 +122,7 @@ defmodule Pleroma.Conversation.Participation do
       RecipientShip.create(users, participation)
       :ok
     end)
+
+    {:ok, Repo.preload(participation, :recipients, force: true)}
   end
 end

test/conversation/participation_test.exs

@@ -132,4 +132,23 @@ defmodule Pleroma.Conversation.ParticipationTest do
 
     [] = Participation.for_user_with_last_activity_id(user)
   end
+
+  test "it sets recipients, always keeping the owner of the participation even when not explicitly set" do
+    user = insert(:user)
+    other_user = insert(:user)
+
+    {:ok, _activity} = CommonAPI.post(user, %{"status" => ".", "visibility" => "direct"})
+    [participation] = Participation.for_user_with_last_activity_id(user)
+
+    participation = Repo.preload(participation, :recipients)
+
+    assert participation.recipients |> length() == 1
+    assert user in participation.recipients
+
+    {:ok, participation} = Participation.set_recipients(participation, [other_user.id])
+
+    assert participation.recipients |> length() == 2
+    assert user in participation.recipients
+    assert other_user in participation.recipients
+  end
 end