1 files changed, 77 insertions, 0 deletions
diff --git a/lib/pleroma/web/activity_pub/object_validators/add_remove_validator.ex b/lib/pleroma/web/activity_pub/object_validators/add_remove_validator.ex
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+++ b/lib/pleroma/web/activity_pub/object_validators/add_remove_validator.ex
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+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2021 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.Web.ActivityPub.ObjectValidators.AddRemoveValidator do
+  use Ecto.Schema
+
+  import Ecto.Changeset
+  import Pleroma.Web.ActivityPub.ObjectValidators.CommonValidations
+
+  require Pleroma.Constants
+
+  alias Pleroma.EctoType.ActivityPub.ObjectValidators
+  alias Pleroma.User
+
+  @primary_key false
+
+  embedded_schema do
+    field(:id, ObjectValidators.ObjectID, primary_key: true)
+    field(:target)
+    field(:object, ObjectValidators.ObjectID)
+    field(:actor, ObjectValidators.ObjectID)
+    field(:type)
+    field(:to, ObjectValidators.Recipients, default: [])
+    field(:cc, ObjectValidators.Recipients, default: [])
+  end
+
+  def cast_and_validate(data) do
+    {:ok, actor} = User.get_or_fetch_by_ap_id(data["actor"])
+
+    {:ok, actor} = maybe_refetch_user(actor)
+
+    data
+    |> maybe_fix_data_for_mastodon(actor)
+    |> cast_data()
+    |> validate_data(actor)
+  end
+
+  defp maybe_fix_data_for_mastodon(data, actor) do
+    # Mastodon sends pin/unpin objects without id, to, cc fields
+    data
+    |> Map.put_new("id", Pleroma.Web.ActivityPub.Utils.generate_activity_id())
+    |> Map.put_new("to", [Pleroma.Constants.as_public()])
+    |> Map.put_new("cc", [actor.follower_address])
+  end
+
+  defp cast_data(data) do
+    cast(%__MODULE__{}, data, __schema__(:fields))
+  end
+
+  defp validate_data(changeset, actor) do
+    changeset
+    |> validate_required([:id, :target, :object, :actor, :type, :to, :cc])
+    |> validate_inclusion(:type, ~w(Add Remove))
+    |> validate_actor_presence()
+    |> validate_collection_belongs_to_actor(actor)
+    |> validate_object_presence()
+  end
+
+  defp validate_collection_belongs_to_actor(changeset, actor) do
+    validate_change(changeset, :target, fn :target, target ->
+      if target == actor.featured_address do
+        []
+      else
+        [target: "collection doesn't belong to actor"]
+      end
+    end)
+  end
+
+  defp maybe_refetch_user(%User{featured_address: address} = user) when is_binary(address) do
+    {:ok, user}
+  end
+
+  defp maybe_refetch_user(%User{ap_id: ap_id}) do
+    Pleroma.Web.ActivityPub.Transmogrifier.upgrade_user_from_ap_id(ap_id)
+  end
+end