w3c traceparent

.gitignore

@@ -12,5 +12,6 @@ Gemfile.lock
 .ruby-gemset
 .idea
 *.rdb
+.yardoc/
 
 examples/**/node_modules

CHANGELOG.md

@@ -17,6 +17,9 @@
  config.enabled_patches += [:graphql]
  end
  ```
+- Add [W3C traceparent header](https://www.w3.org/TR/trace-context/#traceparent-header) support ([#2310](https://github.com/getsentry/sentry-ruby/pull/2310))
+
+ The SDK now also propagates and accepts incoming W3C `traceparent` headers along with the currently implemented `sentry-trace` and `baggage` headers.
 
 ### Bug Fixes
 

sentry-ruby/lib/sentry-ruby.rb

@@ -44,7 +44,7 @@ module Sentry
  LOGGER_PROGNAME = "sentry".freeze
 
  SENTRY_TRACE_HEADER_NAME = "sentry-trace".freeze
-
+ W3C_TRACEPARENT_HEADER_NAME = "traceparent".freeze
  BAGGAGE_HEADER_NAME = "baggage".freeze
 
  THREAD_LOCAL = :sentry_hub
@@ -533,6 +533,17 @@ def get_traceparent
  get_current_hub.get_traceparent
  end
 
+ # Returns the W3C traceparent header for distributed tracing.
+ # Can be either from the currently active span or the propagation context.
+ #
+ # @see https://www.w3.org/TR/trace-context/#traceparent-header W3C Traceparent specification
+ #
+ # @return [String, nil]
+ def get_w3c_traceparent
+ return nil unless initialized?
+ get_current_hub.get_w3c_traceparent
+ end
+
  # Returns the baggage header for distributed tracing.
  # Can be either from the currently active span or the propagation context.
  #

sentry-ruby/lib/sentry/hub.rb

@@ -265,6 +265,13 @@ def get_traceparent
  current_scope.propagation_context.get_traceparent
  end
 
+ def get_w3c_traceparent
+ return nil unless current_scope
+
+ current_scope.get_span&.get_w3c_traceparent ||
+ current_scope.propagation_context.get_w3c_traceparent
+ end
+
  def get_baggage
  return nil unless current_scope
 
@@ -278,6 +285,9 @@ def get_trace_propagation_headers
  traceparent = get_traceparent
  headers[SENTRY_TRACE_HEADER_NAME] = traceparent if traceparent
 
+ w3c_traceparent = get_w3c_traceparent
+ headers[W3C_TRACEPARENT_HEADER_NAME] = w3c_traceparent if w3c_traceparent
+
  baggage = get_baggage
  headers[BAGGAGE_HEADER_NAME] = baggage if baggage && !baggage.empty?
 

sentry-ruby/lib/sentry/propagation_context.rb

@@ -13,6 +13,17 @@
  "[ \t]*$" # whitespace
  )
 
+ W3C_TRACEPARENT_REGEX = Regexp.new(
+ "^[ \t]*" + # whitespace
+ "([0-9a-f]{2})?" + # version
+ "-?([0-9a-f]{32})?" + # trace_id
+ "-?([0-9a-f]{16})?" + # parent_span_id
+ "-?([0-9a-f]{2})?" + # trace_flags
+ "[ \t]*$" # whitespace
+ )
+
+ W3C_TRACEPARENT_VERSION = '00'
+
  # An uuid that can be used to identify a trace.
  # @return [String]
  attr_reader :trace_id
@@ -42,28 +53,38 @@
 
  if env
  sentry_trace_header = env["HTTP_SENTRY_TRACE"] || env[SENTRY_TRACE_HEADER_NAME]
+ w3c_traceparent_header = env["HTTP_TRACEPARENT"] || env[W3C_TRACEPARENT_HEADER_NAME]
  baggage_header = env["HTTP_BAGGAGE"] || env[BAGGAGE_HEADER_NAME]
 
  if sentry_trace_header
  sentry_trace_data = self.class.extract_sentry_trace(sentry_trace_header)
 
  if sentry_trace_data
  @trace_id, @parent_span_id, @parent_sampled = sentry_trace_data
+ @incoming_trace = true
+ end
+ elsif w3c_traceparent_header
+ traceparent_data = self.class.extract_w3c_traceparent(w3c_traceparent_header)
 
- @baggage =
- if baggage_header && !baggage_header.empty?
- Baggage.from_incoming_header(baggage_header)
- else
- # If there's an incoming sentry-trace but no incoming baggage header,
- # for instance in traces coming from older SDKs,
- # baggage will be empty and frozen and won't be populated as head SDK.
- Baggage.new({})
- end
-
- @baggage.freeze!
+ if traceparent_data
+ @trace_id, @parent_span_id, @parent_sampled = traceparent_data
  @incoming_trace = true
  end
  end
+
+ if @incoming_trace
+ @baggage =
+ if baggage_header && !baggage_header.empty?
+ Baggage.from_incoming_header(baggage_header)
+ else
+ # If there's an incoming sentry-trace but no incoming baggage header,
+ # for instance in traces coming from older SDKs,
+ # baggage will be empty and frozen and won't be populated as head SDK.
+ Baggage.new({})
+ end
+
+ @baggage.freeze!
+ end
  end
 
  @trace_id ||= SecureRandom.uuid.delete("-")
@@ -84,6 +105,20 @@
  [trace_id, parent_span_id, parent_sampled]
  end
 
+ # Extract the trace_id, parent_span_id and parent_sampled values from a W3C traceparent header.
+ #
+ # @param traceparent [String] the traceparent header value from the previous transaction.
+ # @return [Array, nil]
+ def self.extract_w3c_traceparent(traceparent)
+ match = W3C_TRACEPARENT_REGEX.match(traceparent)
+ return nil if match.nil?
+
+ trace_id, parent_span_id, trace_flags = match[2..4]
+ parent_sampled = (trace_flags.hex & 0x01) == 0x01
+
+ [version, trace_id, parent_span_id, parent_sampled]
+ end
+
  # Returns the trace context that can be used to embed in an Event.
  # @return [Hash]
  def get_trace_context
@@ -100,6 +135,12 @@
  "#{trace_id}-#{span_id}"
  end
 
+ # Returns the w3c traceparent header from the propagation context.
+ # @return [String]
+ def get_w3c_traceparent
+ "#{W3C_TRACEPARENT_VERSION}-#{trace_id}-#{span_id}-00"
+ end
+
  # Returns the Baggage from the propagation context or populates as head SDK if empty.
  # @return [Baggage, nil]
  def get_baggage

sentry-ruby/lib/sentry/span.rb

@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 require "securerandom"
+require "sentry/propagation_context"
 require "sentry/metrics/local_aggregator"
 
 module Sentry
@@ -141,6 +142,13 @@ def to_sentry_trace
  "#{@trace_id}-#{@span_id}-#{sampled_flag}"
  end
 
+ # Generates a w3c traceparent header that can be used to connect other transactions.
+ # @return [String]
+ def get_w3c_traceparent
+ trace_flags = @sampled ? '01' : '00'
+ "#{PropagationContext::W3C_TRACEPARENT_VERSION}-#{@trace_id}-#{@span_id}-#{trace_flags}"
+ end
+
  # Generates a W3C Baggage header string for distributed tracing
  # from the incoming baggage stored on the transaction.
  # @return [String, nil]

sentry-ruby/spec/sentry_spec.rb

@@ -777,7 +777,8 @@
  it "returns a Hash of sentry-trace and baggage" do
  expect(described_class.get_trace_propagation_headers).to eq({
  "sentry-trace" => described_class.get_traceparent,
- "baggage" => described_class.get_baggage
+ "baggage" => described_class.get_baggage,
+ "traceparent" => described_class.get_w3c_traceparent
  })
  end
  end