process images async

app/jobs/process_document_job.rb

@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+class ProcessDocumentJob
+  include Sidekiq::Job
+
+  sidekiq_options queue: :images
+
+  def perform(params = {})
+    attachment = ActiveStorage::Attachment.find(params['attachment_id'])
+
+    max_page = [attachment.metadata['pdf']['number_of_pages'].to_i - 1,
+                Templates::ProcessDocument::MAX_NUMBER_OF_PAGES_PROCESSED].min
+
+    Templates::ProcessDocument.generate_document_preview_images(attachment, attachment.download, (1..max_page),
+                                                                concurrency: 1)
+  end
+end