2 files changed, 21 insertions, 1 deletions
diff --git a/actionmailer/lib/action_mailer/preview.rb b/actionmailer/lib/action_mailer/preview.rb
index 33a9faa7e7..33de1dc049 100644
--- a/actionmailer/lib/action_mailer/preview.rb
+++ b/actionmailer/lib/action_mailer/preview.rb
@@ -11,6 +11,14 @@ module ActionMailer
       #
       mattr_accessor :preview_path, instance_writer: false
 
+      # Enable or disable mailer previews through app configuration:
+      #
+      #     config.action_mailer.show_previews = true
+      #
+      # Defaults to true for development environment
+      #
+      mattr_accessor :show_previews, instance_writer: false
+
       # :nodoc:
       mattr_accessor :preview_interceptors, instance_writer: false
       self.preview_interceptors = []
@@ -94,6 +102,10 @@ module ActionMailer
           Base.preview_path
         end
 
+        def show_previews #:nodoc:
+          Base.show_previews
+        end
+
         def inform_preview_interceptors(message) #:nodoc:
           Base.preview_interceptors.each do |interceptor|
             interceptor.previewing_email(message)
diff --git a/actionmailer/lib/action_mailer/railtie.rb b/actionmailer/lib/action_mailer/railtie.rb
index 671551fa53..6f760732e2 100644
--- a/actionmailer/lib/action_mailer/railtie.rb
+++ b/actionmailer/lib/action_mailer/railtie.rb
@@ -18,8 +18,9 @@ module ActionMailer
       options.assets_dir      ||= paths["public"].first
       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?
 
-      if Rails.env.development?
+      if options.show_previews
         options.preview_path  ||= defined?(Rails.root) ? "#{Rails.root}/test/mailers/previews" : nil
       end
 
@@ -37,6 +38,13 @@ module ActionMailer
         register_observers(options.delete(:observers))
 
         options.each { |k,v| send("#{k}=", v) }
+
+        if options.show_previews
+          app.routes.append do
+            get '/rails/mailers'         => "rails/mailers#index"
+            get '/rails/mailers/*path'   => "rails/mailers#preview"
+          end
+        end
       end
     end