render_without_request

class SalesReportWorker < ApplicationController
  include Sidekiq::Worker
  sidekiq_options backtrace: true, retry: false

  self.view_paths = "app/views"                     # Where to look for view templates
  
  def perform(request_ident, params)
    @_response = ActionDispatch::Response.new       # Needed to avoid "ActionController::RackDelegation#content_type 
                                                    # delegated to @_response.content_type, but @_response is nil" error
    ...
      
    html = render template: 'sales_reports/show.js.erb'

    ...
  end
  ...
end