[#71630] Add migration to initialize friendly_id_slugs with current data from projects

https://community.openproject.org/wp/72917

Author: judithroth

db/migrate/20260312121938_initialize_historic_identifiers.rb

@@ -0,0 +1,44 @@
+# frozen_string_literal: true
+
+#-- copyright
+# OpenProject is an open source project management software.
+# Copyright (C) the OpenProject GmbH
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License version 3.
+#
+# OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
+# Copyright (C) 2006-2013 Jean-Philippe Lang
+# Copyright (C) 2010-2013 the ChiliProject Team
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+#
+# See COPYRIGHT and LICENSE files for more details.
+#++
+
+class InitializeHistoricIdentifiers < ActiveRecord::Migration[8.1]
+  def up
+    execute <<~SQL.squish
+      INSERT INTO friendly_id_slugs (slug, sluggable_id, sluggable_type, scope, created_at)
+      SELECT identifier, id, 'Project', NULL, NOW()
+      FROM projects
+      WHERE identifier IS NOT NULL
+    SQL
+  end
+
+  def down
+    # nothing to do / not possible
+  end
+end