module Gapic::LoggingConcerns

def setup_logging logger: :default,
                  stream: nil,
                  formatter: nil,
                  level: nil,
                  system_name: nil,
                  service: nil,
                  endpoint: nil,
                  client_id: nil
  service = LoggingConcerns.normalize_service service
  system_name = LoggingConcerns.normalize_system_name system_name
  logging_env = ENV["GOOGLE_SDK_RUBY_LOGGING_GEMS"].to_s.downcase
  logger = nil if ["false", "none"].include? logging_env
  if logger == :default
    logger = nil
    if ["true", "all"].include?(logging_env) || logging_env.split(",").include?(system_name)
      stream ||= $stderr
      level ||= "DEBUG"
      formatter ||= Google::Logging::StructuredFormatter.new if Google::Cloud::Env.get.logging_agent_expected?
      logger = Logger.new stream, progname: system_name, level: level, formatter: formatter
    end
  end
  @logger = logger
  @stub_logger = StubLogger.new logger: logger,
                                system_name: system_name,
                                service: service,
                                endpoint: endpoint,
                                client_id: client_id
end