discourse/app/serializers/user_summary_serializer.rb

class UserSummarySerializer < ApplicationSerializer
  class TopicSerializer < BasicTopicSerializer
    attributes :like_count, :slug, :created_at
  end

  class ReplySerializer < ApplicationSerializer
    attributes :post_number, :like_count, :created_at
    has_one :topic, serializer: TopicSerializer
  end

  has_many :topics, serializer: TopicSerializer
  has_many :replies, serializer: ReplySerializer, embed: :object
  has_many :badges, serializer: UserBadgeSerializer, embed: :object

  attributes :likes_given,
             :likes_received,
             :posts_read_count,
             :days_visited,
             :topic_count,
             :post_count,
             :time_read

  def include_badges?
    SiteSetting.enable_badges
  end

  def time_read
    AgeWords.age_words(object.time_read)
  end
end