1 files changed, 51 insertions, 0 deletions
diff --git a/lib/active_storage/site/mirror_site.rb b/lib/active_storage/site/mirror_site.rb
new file mode 100644
index 0000000000..ba3ef0ef0e
--- /dev/null
+++ b/lib/active_storage/site/mirror_site.rb
@@ -0,0 +1,51 @@
+class ActiveStorage::Site::MirrorSite < ActiveStorage::Site
+  attr_reader :sites
+
+  def initialize(sites:)
+    @sites = sites
+  end
+
+  def upload(key, io)
+    sites.collect do |site|
+      site.upload key, io
+      io.rewind
+    end
+  end
+
+  def download(key)
+    sites.detect { |site| site.exist?(key) }.download(key)
+  end
+
+  def delete(key)
+    perform_across_sites :delete, key
+  end
+
+  def exist?(key)
+    perform_across_sites(:exist?, key).any?
+  end
+
+
+  def url(key, **options)
+    primary_site.url(key, **options)
+  end
+
+  def byte_size(key)
+    primary_site.byte_size(key)
+  end
+
+  def checksum(key)
+    primary_site.checksum(key)
+  end
+
+  private
+    def primary_site
+      sites.first
+    end
+
+    def perform_across_sites(method, *args)
+      # FIXME: Convert to be threaded
+      sites.collect do |site|
+        site.public_send method, *args
+      end
+    end
+end