Class: Foam::Otel::Ingest::MetricReader

Inherits:
OpenTelemetry::SDK::Metrics::Export::PeriodicMetricReader
  • Object
show all
Defined in:
lib/foam/otel/ingest_metric_reader.rb

Instance Method Summary collapse

Constructor Details

#initialize(exporter:, config:) ⇒ MetricReader

Returns a new instance of MetricReader.



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# File 'lib/foam/otel/ingest_metric_reader.rb', line 19

def initialize(exporter:, config:)
  @foam_config = config
  @foam_claim_checked = false
  @foam_double_claim_warned = false
  @foam_stood_down = false
  # super LAST: the superclass constructor starts the ticker thread,
  # which reads the ivars above via collect.
  super(exporter: exporter)
end

Instance Method Details

#after_fork ⇒ Object

A stood-down tap must stay down across forks; everything else inherits the upstream fork recovery (exporter reset + restart), driven by foam's own Process._fork hook via the @ingest_taps registry (GOTCHAS R7 — upstream only wires after_fork through SDK.configure, which door 2 never runs).



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# File 'lib/foam/otel/ingest_metric_reader.rb', line 49

def after_fork
  return if @foam_stood_down

  super
end

#collect ⇒ Object

Guarded collect (GOTCHAS R6): PeriodicMetricReader#export has NO rescue — a raising collect (or exporter) would kill the reader thread silently and the tap would go dark with no warning. Foam's exporter chain already rescues everything to FAILURE; this guard closes the collect half. Also the metrics double-claim gate (fleet ruling 2c / audit R9): checked once, on the first non-empty collection, BEFORE anything reaches the exporter — a stand-down exports zero duplicates ever.



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# File 'lib/foam/otel/ingest_metric_reader.rb', line 37

def collect
  batch = super
  admit_metrics(batch.is_a?(Array) ? batch : [])
rescue StandardError, SystemStackError
  []
end