You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: batch_count_service.rb
    path of file: ./repos/gitlabhq/app/services/projects
    
    the code of the file until where you have to start completion: # frozen_string_literal: true

# Service class for getting and caching the number of elements of several projects
# Warning: do not user this service with a really large set of projects
# because the service use maps to retrieve the project ids.
module Projects
  class BatchCountService
    def initialize(projects)
      @projects = projects
    
    
    def refresh_cache_and_retrieve_data
      count_services = @projects.map { |project| count_service.new(project) }
      services_by_cache_key = count_services.index_by(&:cache_key)

      results = Gitlab::Instrumentation::RedisClusterValidator.allow_cross_slot_commands do
        Rails.cache.fetch_multi(*services_by_cache_key.keys) do |key|
          service = services_by_cache_key[key]

          global_count[service.project.id].to_i
        end
      end

      results.transform_keys! { |cache_key| services_by_cache_key[cache_key].project }
    end