Module: NewRelic::Agent::AgentHelpers::Startup

Included in:
NewRelic::Agent::Agent
Defined in:
lib/new_relic/agent/agent_helpers/startup.rb

Instance Method Summary collapse

Instance Method Details

#agent_should_start?Boolean

Check to see if the agent should start, returning true if it should.

Returns:

  • (Boolean)


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# File 'lib/new_relic/agent/agent_helpers/startup.rb', line 168

def agent_should_start?
  return false if already_started? || disabled?

  if defer_for_delayed_job?
    ::NewRelic::Agent.logger.debug('Deferring startup for DelayedJob')
    return false
  end

  if defer_for_resque?
    ::NewRelic::Agent.logger.debug('Deferring startup for Resque in case it daemonizes')
    return false
  end

  unless app_name_configured?
    NewRelic::Agent.logger.error('No application name configured.',
      'The agent cannot start without at least one. Please check your ',
      'newrelic.yml and ensure that it is valid and has at least one ',
      "value set for app_name in the #{NewRelic::Control.instance.env} ",
      'environment.')
    return false
  end

  return true
end

#already_started?Boolean

Check whether we have already started, which is an error condition

Returns:

  • (Boolean)


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# File 'lib/new_relic/agent/agent_helpers/startup.rb', line 15

def already_started?
  if started?
    ::NewRelic::Agent.logger.error('Agent Started Already!')
    true
  end
end

#app_name_configured?Boolean

Logs the configured application names

Returns:

  • (Boolean)


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# File 'lib/new_relic/agent/agent_helpers/startup.rb', line 110

def app_name_configured?
  names = Agent.config[:app_name]
  return names.respond_to?(:any?) && names.any?
end

#check_config_and_start_agentObject

Sanity-check the agent configuration and start the agent, setting up the worker thread and the exit handler to shut down the agent



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# File 'lib/new_relic/agent/agent_helpers/startup.rb', line 38

def check_config_and_start_agent
  return unless monitoring? && has_correct_license_key?
  return if using_forking_dispatcher?

  setup_and_start_agent
end

#connect_in_foregroundObject

Connecting in the foreground blocks further startup of the agent until we have a connection - useful in cases where you’re trying to log a very-short-running process and want to get statistics from before a server connection (typically 20 seconds) exists



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# File 'lib/new_relic/agent/agent_helpers/startup.rb', line 120

def connect_in_foreground
  NewRelic::Agent.disable_all_tracing { connect(:keep_retrying => false) }
end

#correct_license_lengthObject

A license key is an arbitrary 40 character string, usually looks something like a SHA1 hash



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# File 'lib/new_relic/agent/agent_helpers/startup.rb', line 156

def correct_license_length
  key = Agent.config[:license_key]

  if key.length == 40
    true
  else
    ::NewRelic::Agent.logger.error("Invalid license key: #{key}")
    false
  end
end

#disabled?Boolean

The agent is disabled when it is not force enabled by the ‘agent_enabled’ option (e.g. in a manual start), or enabled normally through the configuration file

Returns:

  • (Boolean)


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# File 'lib/new_relic/agent/agent_helpers/startup.rb', line 196

def disabled?
  !Agent.config[:agent_enabled]
end

#has_correct_license_key?Boolean

A correct license key exists and is of the proper length

Returns:

  • (Boolean)


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# File 'lib/new_relic/agent/agent_helpers/startup.rb', line 150

def has_correct_license_key?
  has_license_key? && correct_license_length
end

#has_license_key?Boolean

Tell the user when the license key is missing so they can fix it by adding it to the file

Returns:

  • (Boolean)


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# File 'lib/new_relic/agent/agent_helpers/startup.rb', line 137

def has_license_key?
  if Agent.config[:license_key] && Agent.config[:license_key].length > 0
    true
  else
    ::NewRelic::Agent.logger.warn('No license key found. ' +
      'This often means your newrelic.yml file was not found, or it lacks a section for the running ' \
      "environment, '#{NewRelic::Control.instance.env}'. You may also want to try linting your newrelic.yml " \
      'to ensure it is valid YML.')
    false
  end
end

#log_app_nameObject



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# File 'lib/new_relic/agent/agent_helpers/startup.rb', line 89

def log_app_name
  ::NewRelic::Agent.logger.info("Application: #{Agent.config[:app_name].join(', ')}")
end

#log_dispatcherObject

Logs the dispatcher to the log file to assist with debugging. When no debugger is present, logs this fact to assist with proper dispatcher detection



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# File 'lib/new_relic/agent/agent_helpers/startup.rb', line 79

def log_dispatcher
  dispatcher_name = Agent.config[:dispatcher].to_s

  if dispatcher_name.empty?
    ::NewRelic::Agent.logger.info('No known dispatcher detected.')
  else
    ::NewRelic::Agent.logger.info("Dispatcher: #{dispatcher_name}")
  end
end

#log_environmentObject

Log the environment the app thinks it’s running in. Useful in debugging, as this is the key for config YAML lookups.



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# File 'lib/new_relic/agent/agent_helpers/startup.rb', line 72

def log_environment
  ::NewRelic::Agent.logger.info("Environment: #{NewRelic::Control.instance.env}")
end

#log_ignore_url_regexesObject



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# File 'lib/new_relic/agent/agent_helpers/startup.rb', line 93

def log_ignore_url_regexes
  regexes = NewRelic::Agent.config[:'rules.ignore_url_regexes']

  unless regexes.empty?
    ::NewRelic::Agent.logger.info('Ignoring URLs that match the following regexes: ' \
      "#{regexes.map(&:inspect).join(', ')}.")
  end
end

#log_startupObject

Log startup information that we almost always want to know



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# File 'lib/new_relic/agent/agent_helpers/startup.rb', line 64

def log_startup
  log_environment
  log_dispatcher
  log_app_name
end

#log_version_and_pidObject

Classy logging of the agent version and the current pid, so we can disambiguate processes in the log file and make sure they’re running a reasonable version



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# File 'lib/new_relic/agent/agent_helpers/startup.rb', line 105

def log_version_and_pid
  ::NewRelic::Agent.logger.debug("New Relic Ruby agent #{NewRelic::VERSION::STRING} initialized: pid = #{$$}")
end

#monitoring?Boolean

Warn the user if they have configured their agent not to send data, that way we can see this clearly in the log file

Returns:

  • (Boolean)


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# File 'lib/new_relic/agent/agent_helpers/startup.rb', line 126

def monitoring?
  if Agent.config[:monitor_mode]
    true
  else
    ::NewRelic::Agent.logger.warn('Agent configured not to send data in this environment.')
    false
  end
end

#setup_and_start_agent(options = {}) ⇒ Object

This is the shared method between the main agent startup and the after_fork call restarting the thread in deferred dispatchers.

Treatment of @started and env report is important to get right.



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# File 'lib/new_relic/agent/agent_helpers/startup.rb', line 49

def setup_and_start_agent(options = {})
  @started = true
  @harvester.mark_started

  unless in_resque_child_process?
    install_exit_handler
    environment_for_connect
    @harvest_samplers.load_samplers unless Agent.config[:disable_samplers]
  end

  connect_in_foreground if Agent.config[:sync_startup]
  start_worker_thread(options)
end

#startObject

Logs a bunch of data and starts the agent, if needed



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# File 'lib/new_relic/agent/agent_helpers/startup.rb', line 23

def start
  return unless agent_should_start?

  log_startup
  check_config_and_start_agent
  log_version_and_pid

  events.subscribe(:initial_configuration_complete) do
    log_ignore_url_regexes
  end
end

#started?Boolean

True if we have initialized and completed ‘start’

Returns:

  • (Boolean)


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# File 'lib/new_relic/agent/agent_helpers/startup.rb', line 10

def started?
  @started
end