FEATURE: Support backup uploads/downloads directly to/from S3.

app/models/backup_file.rb

@@ -0,0 +1,25 @@
+class BackupFile
+  include ActiveModel::SerializerSupport
+
+  attr_reader :filename,
+              :size,
+              :last_modified,
+              :source
+
+  def initialize(filename:, size:, last_modified:, source: nil)
+    @filename = filename
+    @size = size
+    @last_modified = last_modified
+    @source = source
+  end
+
+  def ==(other)
+    attributes == other.attributes
+  end
+
+  protected
+
+  def attributes
+    [@filename, @size, @last_modified, @source]
+  end
+end