Create redirect routes on path change

app/models/route.rb

@@ -8,15 +8,17 @@ class Route < ActiveRecord::Base
     presence: true,
     uniqueness: { case_sensitive: false }
-  after_update :rename_descendants
+  after_update :create_redirect_if_path_changed
+  after_update :rename_direct_descendant_routes
   scope :inside_path, -> (path) { where('routes.path LIKE ?', "#{sanitize_sql_like(path)}/%") }
-  def rename_descendants
+  scope :direct_descendant_routes, -> (path) { where('routes.path LIKE ? AND routes.path NOT LIKE ?', "#{sanitize_sql_like(path)}/%", "#{sanitize_sql_like(path)}/%/%") }
+  def rename_direct_descendant_routes
     if path_changed? || name_changed?
-      descendants = self.class.inside_path(path_was)
-      descendants.each do |route|
+      direct_descendant_routes = self.class.direct_descendant_routes(path_was)
+      direct_descendant_routes.each do |route|
         attributes = {}
         if path_changed? && route.path.present?
@@ -27,10 +29,18 @@ class Route < ActiveRecord::Base
           attributes[:name] = route.name.sub(name_was, name)
         end
-        # Note that update_columns skips validation and callbacks.
-        # We need this to avoid recursive call of rename_descendants method
-        route.update_columns(attributes) unless attributes.empty?
+        route.update(attributes) unless attributes.empty?
       end
     end
   end
+
+  def create_redirect_if_path_changed
+    if path_changed?
+      create_redirect(path_was)
+    end
+  end
+
+  def create_redirect(old_path)
+    source.redirect_routes.create(path: old_path)
+  end
 end

spec/models/route_spec.rb

@@ -26,7 +26,20 @@ describe Route, models: true do
     end
   end
-  describe '#rename_descendants' do
+  describe '.direct_descendant_routes' do
+    let!(:nested_group) { create(:group, path: 'test', name: 'test', parent: group) }
+    let!(:deep_nested_group) { create(:group, path: 'foo', name: 'foo', parent: nested_group) }
+    let!(:another_group) { create(:group, path: 'other') }
+    let!(:similar_group) { create(:group, path: 'gitllab') }
+    let!(:another_group_nested) { create(:group, path: 'another', name: 'another', parent: similar_group) }
+
+    it 'returns correct routes' do
+      expect(Route.direct_descendant_routes('git_lab')).to match_array([nested_group.route])
+      expect(Route.direct_descendant_routes('git_lab/test')).to match_array([deep_nested_group.route])
+    end
+  end
+
+  describe '#rename_direct_descendant_routes' do
     let!(:nested_group) { create(:group, path: 'test', name: 'test', parent: group) }
     let!(:deep_nested_group) { create(:group, path: 'foo', name: 'foo', parent: nested_group) }
     let!(:similar_group) { create(:group, path: 'gitlab-org', name: 'gitlab-org') }
@@ -77,4 +90,23 @@ describe Route, models: true do
       end
     end
   end
+
+  describe '#create_redirect_if_path_changed' do
+    context 'if the path changed' do
+      it 'creates a RedirectRoute for the old path' do
+        route.path = 'new-path'
+        route.save!
+        redirect = route.source.redirect_routes.first
+        expect(redirect.path).to eq('git_lab')
+      end
+    end
+
+    context 'if the path did not change' do
+      it 'does not create a RedirectRoute' do
+        route.updated_at = Time.zone.now.utc
+        route.save!
+        expect(route.source.redirect_routes).to be_empty
+      end
+    end
+  end
 end