From https://once.com/writebook

app/models/book/sluggable.rb

@@ -0,0 +1,11 @@
+module Book::Sluggable
+  extend ActiveSupport::Concern
+
+  included do
+    before_save :generate_slug, if: -> { slug.blank? }
+  end
+
+  def generate_slug
+    self.slug = title.parameterize
+  end
+end