Move project shorthand url helper generation from initializers

Initializers run only once while booting the application therefore on
development and test environments, if we add a new route, the shorthand
url helpers for `projects` resource will not be available until we
reboot the project unless we don't move the logic to correct place.

config/application.rb

@@ -368,30 +368,5 @@ module Gitlab
         end
       end
     end
-
-    config.after_initialize do
-      # Devise (see initializers/8_devise.rb) already reloads routes if
-      # eager loading is enabled, so don't do this twice since it's
-      # expensive.
-      Rails.application.reload_routes! unless config.eager_load
-
-      project_url_helpers = Module.new do
-        extend ActiveSupport::Concern
-
-        Gitlab::Application.routes.named_routes.helper_names.each do |name|
-          next unless name.include?('namespace_project')
-
-          define_method(name.sub('namespace_project', 'project')) do |project, *args|
-            send(name, project&.namespace, project, *args)
-          end
-        end
-      end
-
-      # We add the MilestonesRoutingHelper because we know that this does not
-      # conflict with the methods defined in `project_url_helpers`, and we want
-      # these methods available in the same places.
-      Gitlab::Routing.add_helpers(project_url_helpers)
-      Gitlab::Routing.add_helpers(TimeboxesRoutingHelper)
-    end
   end
 end

config/initializers/zz_metrics.rb

@@ -154,9 +154,13 @@ if Gitlab::Metrics.enabled? && !Rails.env.test? && !(Rails.env.development? && d
   # of the ActiveRecord methods. This has to take place _after_ initializing as
   # for some unknown reason calling eager_load! earlier breaks Devise.
   Gitlab::Application.config.after_initialize do
-    Rails.application.eager_load!
+    # We should move all the logic of this file to somewhere else
+    # and require it after `Rails.application.initialize!` in `environment.rb` file.
+    models_path = Rails.root.join('app', 'models').to_s
 
-    models = Rails.root.join('app', 'models').to_s
+    Dir.glob("**/*.rb", base: models_path).sort.each do |file|
+      require_dependency file
+    end
 
     regex = Regexp.union(
       ActiveRecord::Querying.public_instance_methods(false).map(&:to_s)
@@ -172,7 +176,7 @@ if Gitlab::Metrics.enabled? && !Rails.env.test? && !(Rails.env.development? && d
         else
           loc = method.source_location
 
-          loc && loc[0].start_with?(models) && method.source =~ regex
+          loc && loc[0].start_with?(models_path) && method.source =~ regex
         end
       end
 

config/routes.rb

@@ -288,7 +288,28 @@ Rails.application.routes.draw do
     get '/sitemap' => 'sitemap#show', format: :xml
   end
 
+  # Creates shorthand helper methods for project resources.
+  # For example; for the `namespace_project_path` this also creates `project_path`.
+  #
+  # TODO: We don't need the `Gitlab::Routing` module at all as we can use
+  # the `direct` DSL method of Rails to define url helpers. Move all the
+  # custom url helpers to use the `direct` DSL method and remove the `Gitlab::Routing`.
+  # For more information: https://gitlab.com/gitlab-org/gitlab/-/issues/299583
+  Gitlab::Application.routes.set.filter_map { |route| route.name if route.name&.include?('namespace_project') }.each do |name|
+    new_name = name.sub('namespace_project', 'project')
+
+    direct(new_name) do |project, *args|
+      # This is due to a bug I've found in Rails.
+      # For more information: https://gitlab.com/gitlab-org/gitlab/-/issues/299591
+      args.pop if args.last == {}
+
+      send("#{name}_url", project&.namespace, project, *args)
+    end
+  end
+
   root to: "root#index"
 
   get '*unmatched_route', to: 'application#route_not_found'
 end
+
+Gitlab::Routing.add_helpers(TimeboxesRoutingHelper)