What is the officially supported way to customize the topic RSS output by replacing the default show.rss.erb template?

Support
, ,
1

Objective

  • Replace the original Discourse template at discourse/app/views/topics/show.rss.erb.
  • Place a custom template in the plugin directory: discourse-XXX/app/views/topics/show.rss.erb.
  • Aim: Have RSS pages load the plugin template instead of the original template.

Attempted Approaches and Results

Approach 1: Directly placing the custom template in the plugin directory

  • Action: Put the custom show.rss.erb into discourse-XXX/app/views/topics/.
  • Result: The original template is still used; the RSS page does not load the plugin template.

Approach 2: after_initialize with prepend_view_path

after_initialize do
  class ::TopicsController
    prepend_view_path File.expand_path("../app/views", __dir__)
  end
end
  • Result: The plugin template is ignored; the RSS page continues to use the original template.

Approach 3: after_initialize with prepend_view_path pointing to the plugin directory

after_initialize do
  class ::TopicsController
    prepend_view_path Rails.root.join("plugins/discourse-XXX-plugin-name/app/views")
  end
end
  • Result: The plugin template is still not used; the RSS page continues to render the original template.

Approach 4: Overriding the feed method and explicitly rendering the plugin template

class ::TopicsController
  prepend_view_path Rails.root.join("plugins/discourse-XXX/app/views")

  alias_method :original_feed, :feed
  def feed
    raise Discourse::NotFound if !Post.exists?(topic_id: params[:topic_id])

    begin
      @topic_view = TopicView.new(params[:topic_id])
    rescue Discourse::NotLoggedIn
      raise Discourse::NotFound
    rescue Discourse::InvalidAccess => ex
      deleted =
        guardian.can_see_topic?(ex.obj, false) ||
        (!guardian.can_see_topic?(ex.obj) && ex.obj&.access_topic_via_group && ex.obj.deleted_at)

      raise Discourse::NotFound.new(
        nil,
        check_permalinks: deleted,
        original_path: ex.obj.relative_url,
      )
    end

    @first_post = @topic_view.posts.first

    discourse_expires_in 1.minute
    response.headers["X-Robots-Tag"] = "noindex, nofollow"

    render file: Rails.root.join("plugins/discourse-XXX/app/views/topics/show.rss.erb"), formats: [:rss]
  end
end
  • Result: The plugin template appears to be called, but visiting a topic’s .rss page results in an oops error.

I hope this report clearly summarizes the attempts and the issues encountered. I would greatly appreciate any insights, suggestions, or solutions from the community to successfully replace the show.rss.erb template. Thank you in advance for your help!