Backport r22551 from trunk to 5.0-stable (#39862).

git-svn-id: https://svn.redmine.org/redmine/branches/5.0-stable@22553 e93f8b46-1217-0410-a6f0-8f06a7374b81

config/routes.rb

@@ -312,7 +312,9 @@ Rails.application.routes.draw do
   get 'attachments/download/:id', :to => 'attachments#download', :id => /\d+/
   get 'attachments/thumbnail/:id(/:size)', :to => 'attachments#thumbnail', :id => /\d+/, :size => /\d+/, :as => 'thumbnail'
   resources :attachments, :only => [:show, :update, :destroy]
-  constraints object_type: /(issues|versions|news|messages|wiki_pages|projects|documents|journals)/ do
+
+  # register plugin object types with ObjectTypeConstraint.register_object_type(PluginModel.name.underscore.pluralize')
+  constraints Redmine::Acts::Attachable::ObjectTypeConstraint do
     get 'attachments/:object_type/:object_id/edit', :to => 'attachments#edit_all', :as => :object_attachments_edit
     patch 'attachments/:object_type/:object_id', :to => 'attachments#update_all', :as => :object_attachments
     get 'attachments/:object_type/:object_id/download', :to => 'attachments#download_all', :as => :object_attachments_download

lib/plugins/acts_as_attachable/lib/acts_as_attachable.rb

@@ -20,6 +20,30 @@
 module Redmine
   module Acts
     module Attachable
+
+      class ObjectTypeConstraint
+        cattr_accessor :object_types
+
+        self.object_types = Concurrent::Set.new(%w[
+          issues versions news messages wiki_pages projects documents journals
+        ])
+
+        class << self
+          def matches?(request)
+            request.path_parameters[:object_type] =~ param_expression
+          end
+
+          def register_object_type(type)
+            object_types << type
+            @param_expression = nil
+          end
+
+          def param_expression
+            @param_expression ||= Regexp.new("^(#{object_types.join("|")})$")
+          end
+        end
+      end
+
       def self.included(base)
         base.extend ClassMethods
       end