Module: Foam::Otel::Errors

Defined in:
lib/foam/otel/errors.rb

Overview

One exception, one event (contract SPEC.md section 12): every capture path — the Rack middleware's unhandled-raise rescue, the railtie's process_action notification hook, the error-tracker bridge, and the public record_exception API — records through here, deduped per span by exception object identity.

The seen-set lives ON the span object (an instance variable), not in a thread-local: a request span can be recorded on one thread and finished on another (ActionController::Live streams the response body from a separate thread), so a thread-local would both miss the dedupe/recorded check across threads and leak entries for spans that never pass back through their owning thread. Span-carried state is GC'd with the span and travels with it across threads.

Constant Summary collapse

IVAR = 
:@__foam_otel_recorded

Class Method Summary collapse

Class Method Details

.record_once(span, error) ⇒ Object

Records error on span (exception event + status ERROR) unless this exact exception object was already recorded there. Never raises.



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# File 'lib/foam/otel/errors.rb', line 25

def record_once(span, error)
  return false unless span.respond_to?(:context) && span.context.valid?
  return false unless span.respond_to?(:recording?) && span.recording?

  seen = span.instance_variable_get(IVAR)
  unless seen
    seen = []
    span.instance_variable_set(IVAR, seen)
  end
  return false if seen.include?(error.object_id)

  seen << error.object_id
  span.record_exception(error)
  span.status = OpenTelemetry::Trace::Status.error(error.message.to_s)
  true
rescue StandardError
  false
end

.recorded?(span) ⇒ Boolean

Whether any exception has been recorded on this span (so a later OK status never clobbers a thrown-then-mapped ERROR — SPEC section 6).

Returns:

  • (Boolean) 


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# File 'lib/foam/otel/errors.rb', line 46

def recorded?(span)
  seen = span.instance_variable_get(IVAR)
  !seen.nil? && !seen.empty?
rescue StandardError
  false
end