Function getOtlpReaders

src/utils/telemetry/instrumentation.ts:130–215

()

}

async function getOtlpReaders() {
  const exporterTypes = parseExporterTypes(process.env.OTEL_METRICS_EXPORTER)
  const exportInterval = parseInt(
    process.env.OTEL_METRIC_EXPORT_INTERVAL ||
      DEFAULT_METRICS_EXPORT_INTERVAL_MS.toString(),
  )

  const exporters = []
  for (const exporterType of exporterTypes) {
    if (exporterType === 'console') {
      // Custom console exporter that shows resource attributes
      const consoleExporter = new ConsoleMetricExporter()
      const originalExport = consoleExporter.export.bind(consoleExporter)

      consoleExporter.export = (metrics, callback) => {
        // Log resource attributes once at the start
        if (metrics.resource && metrics.resource.attributes) {
          // The console exporter is for debugging, so console output is intentional here

          logForDebugging('\n=== Resource Attributes ===')
          logForDebugging(jsonStringify(metrics.resource.attributes))
          logForDebugging('===========================\n')
        }

        return originalExport(metrics, callback)
      }

      exporters.push(consoleExporter)
    } else if (exporterType === 'otlp') {
      const protocol =
        process.env.OTEL_EXPORTER_OTLP_METRICS_PROTOCOL?.trim() ||
        process.env.OTEL_EXPORTER_OTLP_PROTOCOL?.trim()

      const httpConfig = getOTLPExporterConfig()

      switch (protocol) {
        case 'grpc': {
          // Lazy-import to keep @grpc/grpc-js (~700KB) out of the telemetry chunk
          // when the protocol is http/protobuf (ant default) or http/json.
          const { OTLPMetricExporter } = await import(
            '@opentelemetry/exporter-metrics-otlp-grpc'
          )
          exporters.push(new OTLPMetricExporter())
          break
        }
        case 'http/json': {
          const { OTLPMetricExporter } = await import(
            '@opentelemetry/exporter-metrics-otlp-http'
          )
          exporters.push(new OTLPMetricExporter(httpConfig))
          break
        }
        case 'http/protobuf': {
          const { OTLPMetricExporter } = await import(
            '@opentelemetry/exporter-metrics-otlp-proto'
          )
          exporters.push(new OTLPMetricExporter(httpConfig))
          break