Undoing: Move undoing likes to the pipeline everywhere.

lib/pleroma/user.ex

@@ -29,7 +29,9 @@ defmodule Pleroma.User do
   alias Pleroma.UserRelationship
   alias Pleroma.Web
   alias Pleroma.Web.ActivityPub.ActivityPub
+  alias Pleroma.Web.ActivityPub.Builder
   alias Pleroma.Web.ActivityPub.ObjectValidators.Types
+  alias Pleroma.Web.ActivityPub.Pipeline
   alias Pleroma.Web.ActivityPub.Utils
   alias Pleroma.Web.CommonAPI
   alias Pleroma.Web.CommonAPI.Utils, as: CommonUtils
@@ -1553,11 +1555,13 @@ defmodule Pleroma.User do
   end
 
   defp delete_activity(%{data: %{"type" => "Like"}} = activity) do
-    object = Object.normalize(activity)
+    actor =
+      activity.actor
+      |> get_cached_by_ap_id()
 
-    activity.actor
-    |> get_cached_by_ap_id()
-    |> ActivityPub.unlike(object)
+    {:ok, undo, _} = Builder.undo(actor, activity)
+
+    Pipeline.common_pipeline(undo, local: true)
   end
 
   defp delete_activity(%{data: %{"type" => "Announce"}} = activity) do

lib/pleroma/web/activity_pub/activity_pub.ex

@@ -398,29 +398,6 @@ defmodule Pleroma.Web.ActivityPub.ActivityPub do
     end
   end
 
-  @spec unlike(User.t(), Object.t(), String.t() | nil, boolean()) ::
-          {:ok, Activity.t(), Activity.t(), Object.t()} | {:ok, Object.t()} | {:error, any()}
-  def unlike(%User{} = actor, %Object{} = object, activity_id \\ nil, local \\ true) do
-    with {:ok, result} <-
-           Repo.transaction(fn -> do_unlike(actor, object, activity_id, local) end) do
-      result
-    end
-  end
-
-  defp do_unlike(actor, object, activity_id, local) do
-    with %Activity{} = like_activity <- get_existing_like(actor.ap_id, object),
-         unlike_data <- make_unlike_data(actor, like_activity, activity_id),
-         {:ok, unlike_activity} <- insert(unlike_data, local),
-         {:ok, _activity} <- Repo.delete(like_activity),
-         {:ok, object} <- remove_like_from_object(like_activity, object),
-         :ok <- maybe_federate(unlike_activity) do
-      {:ok, unlike_activity, like_activity, object}
-    else
-      nil -> {:ok, object}
-      {:error, error} -> Repo.rollback(error)
-    end
-  end
-
   @spec announce(User.t(), Object.t(), String.t() | nil, boolean(), boolean()) ::
           {:ok, Activity.t(), Object.t()} | {:error, any()}
   def announce(

lib/pleroma/web/activity_pub/side_effects.ex

@@ -5,8 +5,10 @@ defmodule Pleroma.Web.ActivityPub.SideEffects do
   liked object, a `Follow` activity will add the user to the follower
   collection, and so on.
   """
+  alias Pleroma.Activity
   alias Pleroma.Notification
   alias Pleroma.Object
+  alias Pleroma.Repo
   alias Pleroma.Web.ActivityPub.Utils
 
   def handle(object, meta \\ [])
@@ -23,8 +25,25 @@ defmodule Pleroma.Web.ActivityPub.SideEffects do
     {:ok, object, meta}
   end
 
+  def handle(%{data: %{"type" => "Undo", "object" => undone_object}} = object, meta) do
+    with undone_object <- Activity.get_by_ap_id(undone_object),
+         :ok <- handle_undoing(undone_object) do
+      {:ok, object, meta}
+    end
+  end
+
   # Nothing to do
   def handle(object, meta) do
     {:ok, object, meta}
   end
+
+  def handle_undoing(%{data: %{"type" => "Like"}} = object) do
+    with %Object{} = liked_object <- Object.get_by_ap_id(object.data["object"]),
+         {:ok, _} <- Utils.remove_like_from_object(object, liked_object),
+         {:ok, _} <- Repo.delete(object) do
+      :ok
+    end
+  end
+
+  def handle_undoing(object), do: {:error, ["don't know how to handle", object]}
 end

lib/pleroma/web/activity_pub/transmogrifier.ex

@@ -865,19 +865,12 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
   def handle_incoming(
         %{
           "type" => "Undo",
-          "object" => %{"type" => "Like", "object" => object_id},
-          "actor" => _actor,
-          "id" => id
+          "object" => %{"type" => "Like"}
         } = data,
         _options
       ) do
-    with actor <- Containment.get_actor(data),
-         {:ok, %User{} = actor} <- User.get_or_fetch_by_ap_id(actor),
-         {:ok, object} <- get_obj_helper(object_id),
-         {:ok, activity, _, _} <- ActivityPub.unlike(actor, object, id, false) do
+    with {:ok, activity, _} <- Pipeline.common_pipeline(data, local: false) do
       {:ok, activity}
-    else
-      _e -> :error
     end
   end
 

lib/pleroma/web/common_api/common_api.ex

@@ -166,9 +166,12 @@ defmodule Pleroma.Web.CommonAPI do
 
   def unfavorite(id, user) do
     with {_, %Activity{data: %{"type" => "Create"}} = activity} <-
-           {:find_activity, Activity.get_by_id(id)} do
-      object = Object.normalize(activity)
-      ActivityPub.unlike(user, object)
+           {:find_activity, Activity.get_by_id(id)},
+         %Object{} = note <- Object.normalize(activity, false),
+         %Activity{} = like <- Utils.get_existing_like(user.ap_id, note),
+         {:ok, undo, _} <- Builder.undo(user, like),
+         {:ok, activity, _} <- Pipeline.common_pipeline(undo, local: false) do
+      {:ok, activity}
     else
       {:find_activity, _} -> {:error, :not_found}
       _ -> {:error, dgettext("errors", "Could not unfavorite")}

lib/pleroma/web/mastodon_api/controllers/status_controller.ex

@@ -222,9 +222,9 @@ defmodule Pleroma.Web.MastodonAPI.StatusController do
   end
 
   @doc "POST /api/v1/statuses/:id/unfavourite"
-  def unfavourite(%{assigns: %{user: user}} = conn, %{"id" => ap_id_or_id}) do
-    with {:ok, _, _, %{data: %{"id" => id}}} <- CommonAPI.unfavorite(ap_id_or_id, user),
-         %Activity{} = activity <- Activity.get_create_by_object_ap_id(id) do
+  def unfavourite(%{assigns: %{user: user}} = conn, %{"id" => activity_id}) do
+    with {:ok, _unfav} <- CommonAPI.unfavorite(activity_id, user),
+         %Activity{} = activity <- Activity.get_by_id(activity_id) do
       try_render(conn, "show.json", activity: activity, for: user, as: :activity)
     end
   end

test/notification_test.exs

@@ -724,7 +724,7 @@ defmodule Pleroma.NotificationTest do
 
       assert length(Notification.for_user(user)) == 1
 
-      {:ok, _, _, _} = CommonAPI.unfavorite(activity.id, other_user)
+      {:ok, _} = CommonAPI.unfavorite(activity.id, other_user)
 
       assert Enum.empty?(Notification.for_user(user))
     end

test/web/activity_pub/activity_pub_test.exs

@@ -995,66 +995,6 @@ defmodule Pleroma.Web.ActivityPub.ActivityPubTest do
     end
   end
 
-  describe "unliking" do
-    test_with_mock "sends an activity to federation", Federator, [:passthrough], [] do
-      Config.put([:instance, :federating], true)
-
-      note_activity = insert(:note_activity)
-      object = Object.normalize(note_activity)
-      user = insert(:user)
-
-      {:ok, object} = ActivityPub.unlike(user, object)
-      refute called(Federator.publish())
-
-      {:ok, _like_activity} = CommonAPI.favorite(user, note_activity.id)
-      object = Object.get_by_id(object.id)
-      assert object.data["like_count"] == 1
-
-      {:ok, unlike_activity, _, object} = ActivityPub.unlike(user, object)
-      assert object.data["like_count"] == 0
-
-      assert called(Federator.publish(unlike_activity))
-    end
-
-    test "reverts unliking on error" do
-      note_activity = insert(:note_activity)
-      user = insert(:user)
-
-      {:ok, like_activity} = CommonAPI.favorite(user, note_activity.id)
-      object = Object.normalize(note_activity)
-      assert object.data["like_count"] == 1
-
-      with_mock(Utils, [:passthrough], maybe_federate: fn _ -> {:error, :reverted} end) do
-        assert {:error, :reverted} = ActivityPub.unlike(user, object)
-      end
-
-      assert Object.get_by_ap_id(object.data["id"]) == object
-      assert object.data["like_count"] == 1
-      assert Activity.get_by_id(like_activity.id)
-    end
-
-    test "unliking a previously liked object" do
-      note_activity = insert(:note_activity)
-      object = Object.normalize(note_activity)
-      user = insert(:user)
-
-      # Unliking something that hasn't been liked does nothing
-      {:ok, object} = ActivityPub.unlike(user, object)
-      assert object.data["like_count"] == 0
-
-      {:ok, like_activity} = CommonAPI.favorite(user, note_activity.id)
-
-      object = Object.get_by_id(object.id)
-      assert object.data["like_count"] == 1
-
-      {:ok, unlike_activity, _, object} = ActivityPub.unlike(user, object)
-      assert object.data["like_count"] == 0
-
-      assert Activity.get_by_id(like_activity.id) == nil
-      assert note_activity.actor in unlike_activity.recipients
-    end
-  end
-
   describe "announcing an object" do
     test "adds an announce activity to the db" do
       note_activity = insert(:note_activity)

test/web/activity_pub/side_effects_test.exs

@@ -5,6 +5,7 @@
 defmodule Pleroma.Web.ActivityPub.SideEffectsTest do
   use Pleroma.DataCase
 
+  alias Pleroma.Activity
   alias Pleroma.Notification
   alias Pleroma.Object
   alias Pleroma.Repo
@@ -15,6 +16,34 @@ defmodule Pleroma.Web.ActivityPub.SideEffectsTest do
 
   import Pleroma.Factory
 
+  describe "Undo objects" do
+    setup do
+      poster = insert(:user)
+      user = insert(:user)
+      {:ok, post} = CommonAPI.post(poster, %{"status" => "hey"})
+      {:ok, like} = CommonAPI.favorite(user, post.id)
+
+      {:ok, undo_data, _meta} = Builder.undo(user, like)
+      {:ok, like_undo, _meta} = ActivityPub.persist(undo_data, local: true)
+
+      %{like_undo: like_undo, post: post, like: like}
+    end
+
+    test "a like undo removes the like from the object", %{like_undo: like_undo, post: post} do
+      {:ok, _like_undo, _} = SideEffects.handle(like_undo)
+
+      object = Object.get_by_ap_id(post.data["object"])
+
+      assert object.data["like_count"] == 0
+      assert object.data["likes"] == []
+    end
+
+    test "deletes the original like", %{like_undo: like_undo, like: like} do
+      {:ok, _like_undo, _} = SideEffects.handle(like_undo)
+      refute Activity.get_by_id(like.id)
+    end
+  end
+
   describe "like objects" do
     setup do
       poster = insert(:user)

test/web/activity_pub/transmogrifier/undo_handling_test.exs

@@ -6,6 +6,7 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier.UndoHandlingTest do
   use Pleroma.DataCase
 
   alias Pleroma.Activity
+  alias Pleroma.Object
   alias Pleroma.User
   alias Pleroma.Web.ActivityPub.Transmogrifier
   alias Pleroma.Web.CommonAPI
@@ -67,7 +68,11 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier.UndoHandlingTest do
     assert data["actor"] == "http://mastodon.example.org/users/admin"
     assert data["type"] == "Undo"
     assert data["id"] == "http://mastodon.example.org/users/admin#likes/2/undo"
-    assert data["object"]["id"] == "http://mastodon.example.org/users/admin#likes/2"
+    assert data["object"] == "http://mastodon.example.org/users/admin#likes/2"
+
+    note = Object.get_by_ap_id(like_data["object"])
+    assert note.data["like_count"] == 0
+    assert note.data["likes"] == []
   end
 
   test "it works for incoming unlikes with an existing like activity and a compact object" do
@@ -94,7 +99,7 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier.UndoHandlingTest do
     assert data["actor"] == "http://mastodon.example.org/users/admin"
     assert data["type"] == "Undo"
     assert data["id"] == "http://mastodon.example.org/users/admin#likes/2/undo"
-    assert data["object"]["id"] == "http://mastodon.example.org/users/admin#likes/2"
+    assert data["object"] == "http://mastodon.example.org/users/admin#likes/2"
   end
 
   test "it works for incoming unannounces with an existing notice" do