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: praefect_manager.rb
    path of file: ./repos/gitlabhq/qa/qa/service
    
    the code of the file until where you have to start completion: # frozen_string_literal: true

require 'digest'

module QA
  module Service
    class PraefectManager
      include Service::Shellout

      attr_accessor :gitlab

      attr_reader :primary_node, :secondary_node, :tertiary_node, :postgres

      PrometheusQueryError = Class.new(StandardError)

      def initialize
        @gitlab = 'gitlab-gitaly-cluster'
      
    
      def verify_storage_move_to_praefect(repo_path, virtual_storage)
        wait_until_shell_command("docker exec #{@praefect} bash -c 'tail -n 50 /var/log/gitlab/praefect/current'") do |line|
          log = JSON.parse(line)

          log['grpc.method'] == 'ReplicateRepository' && log['virtual_storage'] == virtual_storage && log['relative_path'] == repo_path
        rescue JSON::ParserError
          # Ignore lines that can't be parsed as JSON
        end
      end