Class: Datadog::Tracing::Transport::SerializableSpan

Inherits:
Object
  • Object
show all
Defined in:
lib/datadog/tracing/transport/serializable_trace.rb

Overview

Adds serialization functions to a Span

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(span, native_events_supported:) ⇒ SerializableSpan

Returns a new instance of SerializableSpan.

Parameters:

  • span (Datadog::Span) —

    the span to serialize

  • native_events_supported (Boolean) —

    whether the agent supports span events as a top-level field



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# File 'lib/datadog/tracing/transport/serializable_trace.rb', line 53

def initialize(span, native_events_supported:)
  @span = span
  @trace_id = Tracing::Utils::TraceId.to_low_order(span.trace_id)
  @native_events_supported = native_events_supported
end

Instance Attribute Details

#span ⇒ Object (readonly)

Returns the value of attribute span.



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# File 'lib/datadog/tracing/transport/serializable_trace.rb', line 48

def span
  @span
end

Instance Method Details

#duration_nano(duration) ⇒ Integer

Used for serialization

Returns:

  • (Integer) —

    in nanoseconds since Epoch



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# File 'lib/datadog/tracing/transport/serializable_trace.rb', line 149

def duration_nano(duration)
  (duration * 1e9).to_i
end

#time_nano(time) ⇒ Integer

Used for serialization

Returns:

  • (Integer) —

    in nanoseconds since Epoch



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# File 'lib/datadog/tracing/transport/serializable_trace.rb', line 139

def time_nano(time)
  time.to_i * 1000000000 + time.nsec
end

#to_hash ⇒ Object 



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# File 'lib/datadog/tracing/transport/serializable_trace.rb', line 143

def to_hash
  span.to_hash.merge(trace_id: @trace_id)
end

#to_json(*args) ⇒ Object

JSON serializer interface. Used by older version of the transport.



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# File 'lib/datadog/tracing/transport/serializable_trace.rb', line 133

def to_json(*args)
  to_hash.to_json(*args)
end

#to_msgpack(packer = nil) ⇒ Object

MessagePack serializer interface. Making this object respond to ‘#to_msgpack` allows it to be automatically serialized by MessagePack.

This is more efficient than doing MessagePack.pack(span.to_hash) as we don’t have to create an intermediate Hash.

rubocop:disable Metrics/AbcSize rubocop:disable Metrics/MethodLength

Parameters:

  • packer (MessagePack::Packer) (defaults to: nil) —

    serialization buffer, can be nil with JRuby



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# File 'lib/datadog/tracing/transport/serializable_trace.rb', line 69

def to_msgpack(packer = nil)
  packer ||= MessagePack::Packer.new

  number_of_elements_to_write = 12

  number_of_elements_to_write += 1 if span.events.any? && @native_events_supported

  if span.stopped?
    packer.write_map_header(number_of_elements_to_write + 2) # Set header with how many elements in the map

    packer.write('start')
    packer.write(time_nano(span.start_time))

    packer.write('duration')
    packer.write(duration_nano(span.duration))
  else
    packer.write_map_header(number_of_elements_to_write) # Set header with how many elements in the map
  end

  if span.events.any?
    if @native_events_supported
      # Use top-level field for native events
      packer.write('span_events')
      packer.write(span.events.map(&:to_native_format))
    else
      # Serialize span events as meta tags
      span.set_tag('events', span.events.map(&:to_hash).to_json)
    end
  end

  # DEV: We use strings as keys here, instead of symbols, as
  # DEV: MessagePack will ultimately convert them to strings.
  # DEV: By providing strings directly, we skip this indirection operation.
  packer.write('span_id')
  packer.write(span.id)
  packer.write('parent_id')
  packer.write(span.parent_id)
  packer.write('trace_id')
  packer.write(@trace_id)
  packer.write('name')
  packer.write(span.name)
  packer.write('service')
  packer.write(span.service)
  packer.write('resource')
  packer.write(span.resource)
  packer.write('type')
  packer.write(span.type)
  packer.write('meta')
  packer.write(span.meta)
  packer.write('metrics')
  packer.write(span.metrics)
  packer.write('meta_struct')
  packer.write(span.metastruct)
  packer.write('span_links')
  packer.write(span.links.map(&:to_hash))
  packer.write('error')
  packer.write(span.status)
  packer
end