4 files changed, 89 insertions, 0 deletions
diff --git a/lib/pleroma/web/activity_pub/builder.ex b/lib/pleroma/web/activity_pub/builder.ex
index 1aac62c69..135a5c431 100644
--- a/lib/pleroma/web/activity_pub/builder.ex
+++ b/lib/pleroma/web/activity_pub/builder.ex
@@ -123,6 +123,21 @@ defmodule Pleroma.Web.ActivityPub.Builder do
     end
   end
 
+  # Retricted to user updates for now, always public
+  @spec update(User.t(), Object.t()) :: {:ok, map(), keyword()}
+  def update(actor, object) do
+    to = [Pleroma.Constants.as_public(), actor.follower_address]
+
+    {:ok,
+     %{
+       "id" => Utils.generate_activity_id(),
+       "type" => "Update",
+       "actor" => actor.ap_id,
+       "object" => object,
+       "to" => to
+     }, []}
+  end
+
   @spec announce(User.t(), Object.t(), keyword()) :: {:ok, map(), keyword()}
   def announce(actor, object, options \\ []) do
     public? = Keyword.get(options, :public, false)
diff --git a/lib/pleroma/web/activity_pub/object_validator.ex b/lib/pleroma/web/activity_pub/object_validator.ex
index 6a83a2c33..804a9d06e 100644
--- a/lib/pleroma/web/activity_pub/object_validator.ex
+++ b/lib/pleroma/web/activity_pub/object_validator.ex
@@ -19,10 +19,21 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidator do
   alias Pleroma.Web.ActivityPub.ObjectValidators.EmojiReactValidator
   alias Pleroma.Web.ActivityPub.ObjectValidators.LikeValidator
   alias Pleroma.Web.ActivityPub.ObjectValidators.UndoValidator
+  alias Pleroma.Web.ActivityPub.ObjectValidators.UpdateValidator
 
   @spec validate(map(), keyword()) :: {:ok, map(), keyword()} | {:error, any()}
   def validate(object, meta)
 
+  def validate(%{"type" => "Update"} = object, meta) do
+    with {:ok, object} <-
+           object
+           |> UpdateValidator.cast_and_validate()
+           |> Ecto.Changeset.apply_action(:insert) do
+      object = stringify_keys(object)
+      {:ok, object, meta}
+    end
+  end
+
   def validate(%{"type" => "Undo"} = object, meta) do
     with {:ok, object} <-
            object
diff --git a/lib/pleroma/web/activity_pub/object_validators/update_validator.ex b/lib/pleroma/web/activity_pub/object_validators/update_validator.ex
new file mode 100644
index 000000000..94d72491b
--- /dev/null
+++ b/lib/pleroma/web/activity_pub/object_validators/update_validator.ex
@@ -0,0 +1,43 @@
+# 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.ObjectValidators.UpdateValidator do
+  use Ecto.Schema
+
+  alias Pleroma.EctoType.ActivityPub.ObjectValidators
+
+  import Ecto.Changeset
+  import Pleroma.Web.ActivityPub.ObjectValidators.CommonValidations
+
+  @primary_key false
+
+  embedded_schema do
+    field(:id, ObjectValidators.ObjectID, primary_key: true)
+    field(:type, :string)
+    field(:actor, ObjectValidators.ObjectID)
+    field(:to, ObjectValidators.Recipients, default: [])
+    field(:cc, ObjectValidators.Recipients, default: [])
+    # In this case, we save the full object in this activity instead of just a
+    # reference, so we can always see what was actually changed by this.
+    field(:object, :map)
+  end
+
+  def cast_data(data) do
+    %__MODULE__{}
+    |> cast(data, __schema__(:fields))
+  end
+
+  def validate_data(cng) do
+    cng
+    |> validate_required([:id, :type, :actor, :to, :cc, :object])
+    |> validate_inclusion(:type, ["Update"])
+    |> validate_actor_presence()
+  end
+
+  def cast_and_validate(data) do
+    data
+    |> cast_data
+    |> validate_data
+  end
+end
diff --git a/test/web/activity_pub/object_validator_test.exs b/test/web/activity_pub/object_validator_test.exs
index 31224abe0..adb56092d 100644
--- a/test/web/activity_pub/object_validator_test.exs
+++ b/test/web/activity_pub/object_validator_test.exs
@@ -622,4 +622,24 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidatorTest do
       assert {:actor, {"can not announce this object publicly", []}} in cng.errors
     end
   end
+
+  describe "updates" do
+    setup do
+      user = insert(:user)
+
+      object = %{
+        "id" => user.ap_id,
+        "name" => "A new name",
+        "summary" => "A new bio"
+      }
+
+      {:ok, valid_update, []} = Builder.update(user, object)
+
+      %{user: user, valid_update: valid_update}
+    end
+
+    test "validates a basic object", %{valid_update: valid_update} do
+      assert {:ok, _update, []} = ObjectValidator.validate(valid_update, [])
+    end
+  end
 end