Class: Bigcommerce::Lightstep::Tracer

Inherits:
Object
  • Object
show all
Includes:
Singleton
Defined in:
lib/bigcommerce/lightstep/tracer.rb

Overview

Global tracer

Instance Method Summary collapse

Instance Method Details

#active_span ⇒ ::LightStep::Span|NilClass

Return the active span

Returns:

  • (::LightStep::Span|NilClass) 


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# File 'lib/bigcommerce/lightstep/tracer.rb', line 87

def active_span
  Thread.current[:lightstep_active_span]
end

#clear_active_span! ⇒ Object

Clear the active span



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# File 'lib/bigcommerce/lightstep/tracer.rb', line 94

def clear_active_span!
  Thread.current[:lightstep_active_span] = nil
end

#enabled? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/bigcommerce/lightstep/tracer.rb', line 108

def enabled?
  Bigcommerce::Lightstep.enabled
end

#reporter_initialized? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/bigcommerce/lightstep/tracer.rb', line 101

def reporter_initialized?
  tracer.instance_variable_defined?(:@reporter) && !tracer.instance_variable_get(:@reporter).nil?
end

#start_span(name, context: nil, start_time: nil, tags: nil) ⇒ Object

Start a new span

Parameters:

  • name (String) —

    The operation name for the Span

  • context (Hash|::LightStep::SpanContext) (defaults to: nil) —

    (Optional)

  • start_time (Time) (defaults to: nil) —

    (Optional)

  • tags (Hash) (defaults to: nil) —

    (Optional)



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# File 'lib/bigcommerce/lightstep/tracer.rb', line 38

def start_span(name, context: nil, start_time: nil, tags: nil)
  if enabled?
    # enable the tracer (for fork support)
    tracer.enable
  elsif tracer && tracer.enabled?
    # We are not enabled and the tracer is currently on
    # https://github.com/lightstep/lightstep-tracer-ruby/blob/master/lib/lightstep/tracer.rb#L129-L130
    # we have to set this through instance_variable_set because of a bug in the core lightstep gem which
    # assumes the presence of a reporter, which happens in the initializer, which may not be called
    # because the reporter attempts to flush spans on initialization (which is bad if lightstep isn't
    # present)
    tracer.instance_variable_set(:@enabled, false)
  end

  # find the currently active span
  last_active_span = active_span

  # determine who is the actual parent span
  current_parent = determine_parent(context: context)

  # create new span
  span = ::LightStep.start_span(name, child_of: current_parent, start_time: start_time, tags: tags)

  # set it as the active span
  self.active_span = span

  # run the process
  begin
    result = yield span
  rescue StandardError
    span.set_tag('error', true)
    raise
  ensure
    # finish this span if the reporter is initialized
    span.finish if enabled? && reporter_initialized?

    # now set back the parent as the active span
    self.active_span = last_active_span
  end

  # return result
  result
end