Replacing email/notification.html via custom Plugin - tips?

Dev
1

I’ve reached a bit of an impasse and I’m looking for a spot of help.

As part of our switchover to Discourse, we want to change the design of the default email templates and obviously, as only the copy can be changed via the control panel, we figured we’d need to substitute the email templates by building a plugin that allows our email templates to persist between upgrades.

I’ve sussed out how to override the digests, thanks to this thread here:

…however, this doesn’t help when it comes to the notification.html.erb template, which seems to be impervious to ::ActionMailer::Base.prepend_view_path.

Poking into the business end of user_notifications.rb, I noticed this:

html = UserNotificationRenderer.new(Rails.configuration.paths["app/views"]).render(
          template: 'email/notification',
          format: :html,
          locals: { context_posts: context_posts,
                    reached_limit: reached_limit,
                    post: post,
                    in_reply_to_post: in_reply_to_post,
                    classes: Rtl.new(user).css_class
          }
)

I assume this is what is responsible for setting the location of the template file to be used, but see no obvious way to manipulate this without overriding the method in a plugin and admittedly, my experience with Ruby is somewhat limited, so any help you could provide would be very much appreciated.

4 Likes
2

I believe we have plans to make email templates more customizable in the near future, don’t we @awesomerobot?

4 Likes
3

Well, since yesterdaty, I’ve managed to make something happen. I don’t think it’s particularly clean, but here it is.

In my plugin.rb file:

# This attempts to override the Notification Emails by sliding in 
# our custom template directory first.
require_dependency 'user_notifications'
module ::UserNotificationsOverride
    def send_notification_email(opts)
        Rails.configuration.paths["app/views"].unshift(File.expand_path("../templates", __FILE__))
        super(opts)
    end
end

class ::UserNotifications
    prepend ::UserNotificationsOverride
end

…and then adjacent to the plugin file is a template/ directory that contains customised .erb files using the same structure as below /app/views. So my plugin now looks like:

/my-email-plugin
├── plugin.rb
└── templates
    └── email
        ├── _post.html.erb
        ├── invite.html.erb
        ├── notification.html.erb
        └── template.html.erb

What I wanted to do was shift my custom templates folder ahead of the default, in an attempt to replicate what the ::ActionMailer::Base.prepend_view_path line was doing, but without breaking anything else or by carbon-copying the entire send_notification_email method for the sake of changing one line.

If you can think of any ways to improve this, then please do share. :slight_smile:

5 Likes
4

Did this work for you, and does it still work?

I tried creating a plugin using your code in plugin.rb and templates structure, but when I try to rebuild the app after adding the plugin in the containers/app.yml it fails with the following error:

LoadError: No such file to load – user_notifications.rb

5

I’ve figured out what the issue was. The code for plugin.rb needs to be put inside after_initialize:

after_initialize do
    require_dependency 'user_notifications'
    module ::UserNotificationsOverride
        def send_notification_email(opts)
            Rails.configuration.paths["app/views"].unshift(File.expand_path("../templates", __FILE__))
            super(opts)
        end
    end

    class ::UserNotifications
        prepend ::UserNotificationsOverride
    end
end

That’s working fine now for me. Thanks for sharing this method!

2 Likes
6

Note, @neil has just merged this:

https://github.com/discourse/discourse/commit/9656a21fdb0da85a16bff74120a521046867fe42

Does this new core feature resolve the underlying need you had for creating this plugin.

5 Likes
7

The contents of the notification.html.erb and _*post.html.erb templates are still not customizable, so we’ll need to figure out a way to solve those in part 2 of the email customization work.

5 Likes