Add reblogging to MastodonAPI.

lib/pleroma/web/mastodon_api/mastodon_api_controller.ex

@@ -80,4 +80,11 @@ defmodule Pleroma.Web.MastodonAPI.MastodonAPIController do
         |> json(%{error: "Can't delete this post"})
     end
   end
+
+  def reblog_status(%{assigns: %{user: user}} = conn, %{"id" => ap_id_or_id}) do
+    with {:ok, _announce, %{data: %{"id" => id}}} = CommonAPI.repeat(ap_id_or_id, user),
+         %Activity{} = activity <- Activity.get_create_activity_by_object_ap_id(id) do
+      render conn, StatusView, "status.json", %{activity: activity, for: user, as: :activity}
+    end
+  end
 end

lib/pleroma/web/mastodon_api/views/status_view.ex

@@ -7,7 +7,7 @@ defmodule Pleroma.Web.MastodonAPI.StatusView do
     render_many(opts.activities, StatusView, "status.json", opts)
   end
 
-  def render("status.json", %{activity: %{data: %{"object" => object}} = activity}) do
+  def render("status.json", %{activity: %{data: %{"object" => object}} = activity} = opts) do
     user = User.get_cached_by_ap_id(activity.data["actor"])
 
     like_count = object["like_count"] || 0
@@ -21,6 +21,8 @@ defmodule Pleroma.Web.MastodonAPI.StatusView do
     |> Enum.filter(&(&1))
     |> Enum.map(fn (user) -> AccountView.render("mention.json", %{user: user}) end)
 
+    repeated = opts[:for] && opts[:for].ap_id in (object["announcements"] || [])
+
     %{
       id: activity.id,
       uri: object["id"],
@@ -33,7 +35,7 @@ defmodule Pleroma.Web.MastodonAPI.StatusView do
       created_at: object["published"],
       reblogs_count: announcement_count,
       favourites_count: like_count,
-      reblogged: false,
+      reblogged: !!repeated,
       favourited: false, # fix
       muted: false,
       sensitive: sensitive,