rails 4 email preview in production - ruby-on-rails

Question

I am using rails 4.1.1 and ActionMailer::Preview for previewing emails. In development environment everything is working excellent.
But in production environment the preview routes are not accessible. I store the previews in test/mailers/previews/
Is is possible to enable them for production?

Answer 1

In addition to this:
config.action_mailer.show_previews = true
you will also need to set
config.consider_all_requests_local = true
in your environment for the preview routes to be accessible. This has other implications as well (see https://stackoverflow.com/a/373135/1599045) so you likely don't want to enable this in production. However, if you have a custom environment that's not development, the combination of those two should get things working.
EDITED TO ADD:
The original question was for rails 4.1.1, which doesn't have config.action_mailer.show_previews available. To get ActionMailer previews working in non-development environments in rails 4.1.1, you need to first add some routes to config/routes.rb (in this case, my environment is named custom):
if Rails.env.custom?
get '/rails/mailers' => "rails/mailers#index"
get '/rails/mailers/*path' => "rails/mailers#preview"
end
Then you need to autoload the libraries needed in your environment's config file (in my case, config/environments/custom.rb):
config.action_mailer.preview_path ||= defined?(Rails.root) ? "#{Rails.root}/test/mailers/previews" : nil
config.autoload_paths += [config.action_mailer.preview_path]
This seems to perform the same task as config.action_mailer.show_previews does.
As with 4.2, you will still need to adjust the local request configuration as above depending on whether your custom environment is being used locally or on a server.

Answer 2

To do it without opening a big security hole:
production.rb
MyApp::Application.configure do
config.action_mailer.preview_path ||= defined?(Rails.root) ? "#{Rails.root}/spec/mailer_previews" : nil
config.autoload_paths += [config.action_mailer.preview_path]
routes.append do
get '/rails/mailers' => "rails/mailers#index"
get '/rails/mailers/*path' => "rails/mailers#preview"
end
end
class ::Rails::MailersController
before_filter :authenticate_admin!
def local_request?
true
end
private
def authenticate_admin!
...
end
end

Answer 3

It's possible to enable previews in production by config.action_mailer.show_previews = true as the best answer says.
I just want to add how you can render previews in iframe within your own admin area, eg. in active admin (Rails 5.1)
And also I found out that it is not so hard to write your own email previews administration, and don't use rails standard previews at all. You can then add your own features such as changing preview parameters or Send button to see this email in your phone.

Answer 4

From Rails 4.2 you can use the flag in production.rb (or other custom enviroment):
config.action_mailer.show_previews = true
I haven't found anything similar in Rails 4.1.
Update:
If Rspec used, for example, there will be need to add the path:
config.action_mailer.preview_path = "#{Rails.root}/spec/mailers/previews"
Default path is "#{Rails.root}/test/mailers/previews".
And no need to touch config.consider_all_requests_local

Answer 5

Here's what I did for Rails 5.2:
production.rb
config.action_mailer.show_previews = true
config.action_mailer.preview_path ||= defined?(Rails.root) ? "#{Rails.root}/spec/mailers/previews" : nil
class ::Rails::MailersController
include ::ApplicationController::Authorization
before_action :require_admin
end
Assuming your ApplicationController::Authorization module has the code for require_admin. I preferred this approach rather than rewriting my authorization code. Remembering to include the :: in front was tricky, because saying include ApplicationController::... will look within the Rails::MailersController namespace.