1 files changed, 83 insertions, 0 deletions
diff --git a/lib/pleroma/web/activity_pub/object_validator.ex b/lib/pleroma/web/activity_pub/object_validator.ex
new file mode 100644
index 000000000..549e5e761
--- /dev/null
+++ b/lib/pleroma/web/activity_pub/object_validator.ex
@@ -0,0 +1,83 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2020 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.Web.ActivityPub.ObjectValidator do
+  @moduledoc """
+  This module is responsible for validating an object (which can be an activity)
+  and checking if it is both well formed and also compatible with our view of
+  the system.
+  """
+
+  alias Pleroma.Object
+  alias Pleroma.User
+  alias Pleroma.Web.ActivityPub.ObjectValidators.DeleteValidator
+  alias Pleroma.Web.ActivityPub.ObjectValidators.EmojiReactValidator
+  alias Pleroma.Web.ActivityPub.ObjectValidators.LikeValidator
+  alias Pleroma.Web.ActivityPub.ObjectValidators.Types
+  alias Pleroma.Web.ActivityPub.ObjectValidators.UndoValidator
+
+  @spec validate(map(), keyword()) :: {:ok, map(), keyword()} | {:error, any()}
+  def validate(object, meta)
+
+  def validate(%{"type" => "Undo"} = object, meta) do
+    with {:ok, object} <-
+           object
+           |> UndoValidator.cast_and_validate()
+           |> Ecto.Changeset.apply_action(:insert) do
+      object = stringify_keys(object)
+      {:ok, object, meta}
+    end
+  end
+
+  def validate(%{"type" => "Delete"} = object, meta) do
+    with cng <- DeleteValidator.cast_and_validate(object),
+         do_not_federate <- DeleteValidator.do_not_federate?(cng),
+         {:ok, object} <- Ecto.Changeset.apply_action(cng, :insert) do
+      object = stringify_keys(object)
+      meta = Keyword.put(meta, :do_not_federate, do_not_federate)
+      {:ok, object, meta}
+    end
+  end
+
+  def validate(%{"type" => "Like"} = object, meta) do
+    with {:ok, object} <-
+           object |> LikeValidator.cast_and_validate() |> Ecto.Changeset.apply_action(:insert) do
+      object = stringify_keys(object |> Map.from_struct())
+      {:ok, object, meta}
+    end
+  end
+
+  def validate(%{"type" => "EmojiReact"} = object, meta) do
+    with {:ok, object} <-
+           object
+           |> EmojiReactValidator.cast_and_validate()
+           |> Ecto.Changeset.apply_action(:insert) do
+      object = stringify_keys(object |> Map.from_struct())
+      {:ok, object, meta}
+    end
+  end
+
+  def stringify_keys(%{__struct__: _} = object) do
+    object
+    |> Map.from_struct()
+    |> stringify_keys
+  end
+
+  def stringify_keys(object) do
+    object
+    |> Map.new(fn {key, val} -> {to_string(key), val} end)
+  end
+
+  def fetch_actor(object) do
+    with {:ok, actor} <- Types.ObjectID.cast(object["actor"]) do
+      User.get_or_fetch_by_ap_id(actor)
+    end
+  end
+
+  def fetch_actor_and_object(object) do
+    fetch_actor(object)
+    Object.normalize(object["object"])
+    :ok
+  end
+end