add blobs proxy controller

config/initializers/active_storage.rb

@@ -14,13 +14,20 @@ ActiveSupport.on_load(:active_storage_attachment) do
 
     return unless first_page
 
-    Rails.application.routes.url_helpers.rails_storage_proxy_url(first_page, **Docuseal.default_url_options)
+    ActiveStorage::Blob.proxy_url(first_page.blob)
   end
 end
 
 ActiveSupport.on_load(:active_storage_blob) do
   attribute :uuid, :string, default: -> { SecureRandom.uuid }
 
+  def self.proxy_url(blob, expires_in: nil)
+    Rails.application.routes.url_helpers.blobs_proxy_url(
+      signed_uuid: blob.signed_uuid(expires_in:), filename: blob.filename,
+      **Docuseal.default_url_options
+    )
+  end
+
   def uuid
     super || begin
       new_uuid = SecureRandom.uuid
@@ -29,6 +36,10 @@ ActiveSupport.on_load(:active_storage_blob) do
     end
   end
 
+  def signed_uuid(expires_in: nil)
+    ApplicationRecord.signed_id_verifier.generate(uuid, expires_in:)
+  end
+
   def delete
     service.delete(key)
   end

config/routes.rb

@@ -82,6 +82,8 @@ Rails.application.routes.draw do
     resources :submissions_export, only: %i[index new]
   end
   resources :preview_document_page, only: %i[show], path: '/preview/:signed_uuid'
+  resource :blobs_proxy, only: %i[show], path: '/blobs_proxy/:signed_uuid/*filename(.:format)',
+                         controller: 'api/active_storage_blobs_proxy'
 
   resources :start_form, only: %i[show update], path: 'd', param: 'slug' do
     get :completed