detect fields

app/controllers/templates_detect_fields_controller.rb

@@ -0,0 +1,27 @@
+# frozen_string_literal: true
+
+class TemplatesDetectFieldsController < ApplicationController
+  include ActionController::Live
+
+  load_and_authorize_resource :template
+
+  def create
+    response.headers['Content-Type'] = 'text/event-stream'
+
+    sse = SSE.new(response.stream)
+
+    documents = @template.schema_documents.preload(:blob)
+
+    documents.each do |document|
+      io = StringIO.new(document.download)
+
+      Templates::DetectFields.call(io, attachment: document) do |(attachment_uuid, page, fields)|
+        sse.write({ attachment_uuid:, page:, fields: })
+      end
+    end
+
+    sse.write({ completed: true })
+  ensure
+    response.stream.close
+  end
+end