Merge branch 'actionmailer-cache'

This is a rebased version of #22825.

Closes #22825.

2 files changed, 14 insertions, 0 deletions

diff --git a/actionmailer/lib/action_mailer/base.rb b/actionmailer/lib/action_mailer/base.rb
index 4259eb0bee..559cd06d91 100644
--- a/actionmailer/lib/action_mailer/base.rb
+++ b/actionmailer/lib/action_mailer/base.rb
@@ -430,6 +430,7 @@ module ActionMailer
     include AbstractController::Translation
     include AbstractController::AssetPaths
     include AbstractController::Callbacks
+    include AbstractController::Caching
 
     include ActionView::Layouts
 
@@ -947,6 +948,18 @@ module ActionMailer
       container.add_part(part)
     end
 
+    # This and #instrument_name is for caching instrument
+    def instrument_payload(key)
+      {
+        mailer: mailer_name,
+        key: key
+      }
+    end
+
+    def instrument_name
+      "action_mailer"
+    end
+
     ActiveSupport.run_load_hooks(:action_mailer, self)
   end
 end
diff --git a/actionmailer/lib/action_mailer/railtie.rb b/actionmailer/lib/action_mailer/railtie.rb
index ae89492b0f..215d0199af 100644
--- a/actionmailer/lib/action_mailer/railtie.rb
+++ b/actionmailer/lib/action_mailer/railtie.rb
@@ -25,6 +25,7 @@ module ActionMailer
       options.javascripts_dir ||= paths["public/javascripts"].first
       options.stylesheets_dir ||= paths["public/stylesheets"].first
       options.show_previews = Rails.env.development? if options.show_previews.nil?
+      options.cache_store ||= Rails.cache
 
       if options.show_previews
         options.preview_path  ||= defined?(Rails.root) ? "#{Rails.root}/test/mailers/previews" : nil