scinote-web/app/controllers/activities_controller.rb

class ActivitiesController < ApplicationController
  include ActivityHelper

  def index
    @vars = local_vars
    render json: {
      more_url: local_vars.fetch(:more_activities_url),
      html: render_to_string(
        partial: 'list', locals: @vars, formats: :html
      )
    }
  end

  private

  def local_vars
    page = (params[:page] || 1).to_i
    activities = current_user.last_activities
                             .page(page)
                             .per(Constants::ACTIVITY_AND_NOTIF_SEARCH_LIMIT)
    unless activities.blank? || activities.last_page?
      more_url = url_for(
        activities_url(
          format: :json,
          page: page + 1,
          last_activity: activities.last.id
        )
      )
    end
    {
      activities: activities,
      more_activities_url: more_url,
      page: page
    }
  end
end