Conversations: Add a function to 'import' old DMs.

lib/pleroma/conversation.ex

@@ -72,4 +72,18 @@ def create_or_bump_for(activity) do
       e -> {:error, e}
     end
   end
+
+  @doc """
+  This is only meant to be run by a mix task. It creates conversations/participations for all direct messages in the database.
+  """
+  def bump_for_all_activities() do
+    stream =
+      Pleroma.Web.ActivityPub.ActivityPub.fetch_direct_messages_query()
+      |> Repo.stream()
+
+    Repo.transaction(fn ->
+      stream
+      |> Enum.each(&create_or_bump_for/1)
+    end)
+  end
 end

lib/pleroma/web/activity_pub/activity_pub.ex

@@ -1061,4 +1061,10 @@ def contain_timeline(timeline, user) do
       contain_activity(activity, user)
     end)
   end
+
+  def fetch_direct_messages_query() do
+    Activity
+    |> restrict_type(%{"type" => "Create"})
+    |> restrict_visibility(%{visibility: "direct"})
+  end
 end

test/conversation_test.exs

@@ -9,6 +9,24 @@ defmodule Pleroma.ConversationTest do
 
   import Pleroma.Factory
 
+  test "it goes through old direct conversations" do
+    user = insert(:user)
+    other_user = insert(:user)
+
+    {:ok, _activity} =
+      CommonAPI.post(user, %{"visibility" => "direct", "status" => "hey @#{other_user.nickname}"})
+
+    Repo.delete_all(Conversation)
+    Repo.delete_all(Conversation.Participation)
+
+    refute Repo.one(Conversation)
+
+    Conversation.bump_for_all_activities()
+
+    assert Repo.one(Conversation)
+    assert length(Repo.all(Conversation.Participation)) == 2
+  end
+
   test "it creates a conversation for given ap_id" do
     assert {:ok, %Conversation{} = conversation} =
              Conversation.create_for_ap_id("https://some_ap_id")