Class: Datadog::DI::Component Private

Inherits:
Object
  • Object
show all
Defined in:
lib/datadog/di/component.rb

Overview

This class is part of a private API. You should avoid using this class if possible, as it may be removed or be changed in the future.

Component for dynamic instrumentation.

Only one instance of the Component should ever be active; if configuration is changed, the old distance should be shut down prior to the new instance being created.

The Component instance stores all state related to DI, for example which probes have been retrieved via remote config, intalled tracepoints and so on. Component will clean up all resources and installed tracepoints upon shutdown.

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(settings, agent_settings, logger, code_tracker: nil, telemetry: nil) ⇒ Component

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Returns a new instance of Component.



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# File 'lib/datadog/di/component.rb', line 56

def initialize(settings, agent_settings, logger, code_tracker: nil, telemetry: nil)
  @settings = settings
  @agent_settings = agent_settings
  logger = DI::Logger.new(settings, logger)
  @logger = logger
  @telemetry = telemetry
  @code_tracker = code_tracker
  @redactor = Redactor.new(settings)
  @serializer = Serializer.new(settings, redactor, telemetry: telemetry)
  @instrumenter = Instrumenter.new(settings, serializer, logger, code_tracker: code_tracker, telemetry: telemetry)
  @probe_notifier_worker = ProbeNotifierWorker.new(settings, logger, agent_settings: agent_settings, telemetry: telemetry)
  @probe_notification_builder = ProbeNotificationBuilder.new(settings, serializer)
  @probe_manager = ProbeManager.new(settings, instrumenter, probe_notification_builder, probe_notifier_worker, logger, telemetry: telemetry)
  probe_notifier_worker.start
end

Instance Attribute Details

#agent_settingsObject (readonly)

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.



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# File 'lib/datadog/di/component.rb', line 73

def agent_settings
  @agent_settings
end

#code_trackerObject (readonly)

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.



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# File 'lib/datadog/di/component.rb', line 76

def code_tracker
  @code_tracker
end

#instrumenterObject (readonly)

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.



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# File 'lib/datadog/di/component.rb', line 77

def instrumenter
  @instrumenter
end

#loggerObject (readonly)

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.



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# File 'lib/datadog/di/component.rb', line 74

def logger
  @logger
end

#probe_managerObject (readonly)

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.



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# File 'lib/datadog/di/component.rb', line 80

def probe_manager
  @probe_manager
end

#probe_notification_builderObject (readonly)

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.



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# File 'lib/datadog/di/component.rb', line 79

def probe_notification_builder
  @probe_notification_builder
end

#probe_notifier_workerObject (readonly)

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.



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# File 'lib/datadog/di/component.rb', line 78

def probe_notifier_worker
  @probe_notifier_worker
end

#redactorObject (readonly)

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.



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# File 'lib/datadog/di/component.rb', line 81

def redactor
  @redactor
end

#serializerObject (readonly)

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.



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# File 'lib/datadog/di/component.rb', line 82

def serializer
  @serializer
end

#settingsObject (readonly)

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.



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# File 'lib/datadog/di/component.rb', line 72

def settings
  @settings
end

#telemetryObject (readonly)

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.



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# File 'lib/datadog/di/component.rb', line 75

def telemetry
  @telemetry
end

Class Method Details

.build(settings, agent_settings, logger, telemetry: nil) ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.



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# File 'lib/datadog/di/component.rb', line 17

def build(settings, agent_settings, logger, telemetry: nil)
  return unless settings.respond_to?(:dynamic_instrumentation) && settings.dynamic_instrumentation.enabled

  unless settings.respond_to?(:remote) && settings.remote.enabled
    logger.warn("di: dynamic instrumentation could not be enabled because Remote Configuration Management is not available. To enable Remote Configuration, see https://docs.datadoghq.com/agent/remote_config")
    return
  end

  return unless environment_supported?(settings, logger)

  new(settings, agent_settings, logger, code_tracker: DI.code_tracker, telemetry: telemetry).tap do |component|
    DI.add_current_component(component)
  end
end

.environment_supported?(settings, logger) ⇒ Boolean

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Checks whether the runtime environment is supported by dynamic instrumentation. Currently we only require that, if Rails is used, that Rails environment is not development because DI does not currently support code unloading and reloading.

Returns:

  • (Boolean)


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# File 'lib/datadog/di/component.rb', line 36

def environment_supported?(settings, logger)
  # TODO add tests?
  unless settings.dynamic_instrumentation.internal.development
    if Datadog::Core::Environment::Execution.development?
      logger.warn("di: development environment detected; not enabling dynamic instrumentation")
      return false
    end
  end
  if RUBY_ENGINE != 'ruby'
    logger.warn("di: cannot enable dynamic instrumentation: MRI is required, but running on #{RUBY_ENGINE}")
    return false
  end
  if RUBY_VERSION < '2.6'
    logger.warn("di: cannot enable dynamic instrumentation: Ruby 2.6+ is required, but running on #{RUBY_VERSION}")
    return false
  end
  true
end

Instance Method Details

#parse_probe_spec_and_notify(probe_spec) ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.



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# File 'lib/datadog/di/component.rb', line 100

def parse_probe_spec_and_notify(probe_spec)
  probe = ProbeBuilder.build_from_remote_config(probe_spec)
rescue => exc
  begin
    probe = Struct.new(:id).new(
      probe_spec['id'],
    )
    payload = probe_notification_builder.build_errored(probe, exc)
    probe_notifier_worker.add_status(payload)
  rescue # standard:disable Lint/UselessRescue
    # TODO report via instrumentation telemetry?
    raise
  end

  raise
else
  payload = probe_notification_builder.build_received(probe)
  probe_notifier_worker.add_status(payload)
  probe
end

#shutdown!(replacement = nil) ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Shuts down dynamic instrumentation.

Removes all code hooks and stops background threads.

Does not clear out the code tracker, because it’s only populated by code when code is compiled and therefore, if the code tracker was replaced by a new instance, the new instance of it wouldn’t have any of the already loaded code tracked.



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# File 'lib/datadog/di/component.rb', line 92

def shutdown!(replacement = nil)
  DI.remove_current_component(self)

  probe_manager.clear_hooks
  probe_manager.close
  probe_notifier_worker.stop
end