Class: Flare::TraceBlob

Inherits:
Object
  • Object
show all
Defined in:
lib/flare/trace_blob.rb

Overview

Value object that turns a group of OTel span_data for a single trace into the Flare-JSON wire format the server expects:

{
  "trace_id":       "<hex>",
  "trace_rule_id":  <int|nil>,
  "root_name":      "<string>",
  "started_at":     "<iso8601>",
  "duration_ms":    <int>,
  "spans": [
    { "id", "parent_id", "name", "started_at",
      "duration_ms", "attributes" }
  ]
}

The trace_rule_id is read from any span carrying the ‘flare.rule_id` attribute (Path 1 sets it on the sampled root, Path 2 sets it on the rack owner span via WebMarkerSubscriber).

Constant Summary collapse

ZERO_SPAN_ID = 
("\x00".b * 8).freeze
ROOT_NAME_LIMIT = 
255

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(trace_id:, spans:) ⇒ TraceBlob

Returns a new instance of TraceBlob.



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# File 'lib/flare/trace_blob.rb', line 33

def initialize(trace_id:, spans:)
  @trace_id = trace_id
  @spans    = spans
end

Class Method Details

.build(trace_id:, spans:) ⇒ Object 



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# File 'lib/flare/trace_blob.rb', line 28

def self.build(trace_id:, spans:)
  return nil if spans.nil? || spans.empty?
  new(trace_id: trace_id, spans: spans)
end

Instance Method Details

#to_h ⇒ Object 



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# File 'lib/flare/trace_blob.rb', line 38

def to_h
  root = find_root
  {
    "trace_id"      => hexify(@trace_id),
    "trace_rule_id" => rule_id_from_spans,
    "root_name"     => root_name(root),
    "started_at"    => iso(root&.start_timestamp),
    "duration_ms"   => duration_ms(root),
    "spans"         => @spans.map { |s| span_to_h(s) }
  }
end