server - add hidden fields to thread/reply

priv/repo/migrations/20180123042453_thread_add_hidden_field.exs

@@ -0,0 +1,22 @@
+defmodule MyApp.Repo.Migrations.ThreadAddHiddenField do
+  use Ecto.Migration
+  import Ecto.Query
+
+  def up do
+    alter table(:thread) do
+      add :hidden, :boolean
+    end
+
+    flush() 
+
+    from(r in "thread",
+      update: [set: [hidden: false]])
+    |> MyApp.Repo.update_all([])
+  end
+
+  def down do
+    alter table(:thread) do
+      remove :hidden
+    end
+  end
+end