Add a printer job queue via the printer plugin

plugins/printer/db/migrate/20181201000000_create_printer_jobs.rb

@@ -0,0 +1,20 @@
+class CreatePrinterJobs < ActiveRecord::Migration
+  def change
+    create_table :printer_jobs do |t|
+      t.references :order
+      t.string :document, null: false
+      t.integer :created_by_user_id, null: false
+      t.integer :finished_by_user_id
+      t.datetime :finished_at, index: true
+    end
+
+    create_table :printer_job_updates do |t|
+      t.references :printer_job, null: false
+      t.datetime :created_at, null: false
+      t.string :state, null: false
+      t.text :message
+    end
+
+    add_index :printer_job_updates, [:printer_job_id, :created_at]
+  end
+end