Module: Chronos::Core::TraceContext

Defined in:
lib/chronos/core/trace_context.rb

Overview

Parses and formats the W3C Trace Context headers without an OpenTelemetry dependency.

Constant Summary collapse

TRACEPARENT = 
/\A([\da-f]{2})-([\da-f]{32})-([\da-f]{16})-([\da-f]{2})\z/.freeze

Class Method Summary collapse

Class Method Details

.format(context) ⇒ Object 



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# File 'lib/chronos/core/trace_context.rb', line 19

def format(context)
  trace_id = value(context, "trace_id")
  span_id = value(context, "span_id")
  flags = value(context, "trace_flags")
  return nil unless trace_id =~ /\A[\da-f]{32}\z/ && span_id =~ /\A[\da-f]{16}\z/
  return nil if trace_id == ("0" * 32) || span_id == ("0" * 16)

  "00-#{trace_id}-#{span_id}-#{flags =~ /\A[\da-f]{2}\z/ ? flags : '01'}"
rescue StandardError
  nil
end

.parse(value) ⇒ Object 



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# File 'lib/chronos/core/trace_context.rb', line 9

def parse(value)
  match = TRACEPARENT.match(value.to_s.downcase)
  return {} unless match && match[1] == "00"
  return {} if match[2] == ("0" * 32) || match[3] == ("0" * 16)

  {"trace_id" => match[2], "span_id" => match[3], "trace_flags" => match[4]}
rescue StandardError
  {}
end

.value(context, key) ⇒ Object 



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# File 'lib/chronos/core/trace_context.rb', line 31

def value(context, key)
  return "" unless context.is_a?(Hash)

  (context[key] || context[key.to_sym]).to_s.downcase
end