Class: OpenTelemetry::Propagator::XRay::TextMapPropagator

Inherits:
Object
  • Object
show all
Defined in:
lib/opentelemetry/propagator/xray/text_map_propagator.rb

Overview

Propagates context in carriers in the xray single header format

Direct Known Subclasses

LambdaTextMapPropagator

Instance Method Summary collapse

Instance Method Details

#extract(carrier, context: Context.current, getter: Context::Propagation.text_map_getter) ⇒ Context

Extract trace context from the supplied carrier. If extraction fails, the original context will be returned

Parameters:

  • carrier (Carrier) —

    The carrier to get the header from

  • context (optional Context) (defaults to: Context.current) —

    Context to be updated with the trace context extracted from the carrier. Defaults to +Context.current+.

  • getter (optional Getter) (defaults to: Context::Propagation.text_map_getter) —

    If the optional getter is provided, it will be used to read the header from the carrier, otherwise the default text map getter will be used.

Returns:

  • (Context) —

    context updated with extracted baggage, or the original context if extraction fails



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# File 'lib/opentelemetry/propagator/xray/text_map_propagator.rb', line 39

def extract(carrier, context: Context.current, getter: Context::Propagation.text_map_getter)
  header = getter.get(carrier, XRAY_CONTEXT_KEY)
  return context unless header

  match = parse_header(header)
  return context unless match

  span_context = Trace::SpanContext.new(
    trace_id: to_trace_id(match['trace_id']),
    span_id: to_span_id(match['span_id']),
    trace_flags: to_trace_flags(match['sampling_state']),
    tracestate: to_trace_state(match['trace_state']),
    remote: true
  )

  span = OpenTelemetry::Trace.non_recording_span(span_context)
  context = XRay.context_with_debug(context) if match['sampling_state'] == 'd'
  Trace.context_with_span(span, parent_context: context)
rescue OpenTelemetry::Error
  context
end

#inject(carrier, context: Context.current, setter: Context::Propagation.text_map_setter) ⇒ Object

Inject trace context into the supplied carrier.

Parameters:

  • carrier (Carrier) —

    The mutable carrier to inject trace context into

  • context (Context) (defaults to: Context.current) —

    The context to read trace context from

  • setter (optional Setter) (defaults to: Context::Propagation.text_map_setter) —

    If the optional setter is provided, it will be used to write context into the carrier, otherwise the default text map setter will be used.



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# File 'lib/opentelemetry/propagator/xray/text_map_propagator.rb', line 68

def inject(carrier, context: Context.current, setter: Context::Propagation.text_map_setter)
  span_context = Trace.current_span(context).context
  return unless span_context.valid?

  sampling_state = if XRay.debug?(context)
                     'd'
                   elsif span_context.trace_flags.sampled?
                     '1'
                   else
                     '0'
                   end

  ot_trace_id = span_context.hex_trace_id
  xray_trace_id = "1-#{ot_trace_id[0..7]}-#{ot_trace_id[8..ot_trace_id.length]}"
  parent_id = span_context.hex_span_id

  xray_value = "Root=#{xray_trace_id};Parent=#{parent_id};Sampled=#{sampling_state}"

  setter.set(carrier, XRAY_CONTEXT_KEY, xray_value)
  nil
end