traceapm/src/otel.js

SDK for OpenTelemetry auto-instrumentation and OTLP export for Node.js apps.

const { NodeSDK } = require('@opentelemetry/sdk-node');
const { diag, DiagConsoleLogger, DiagLogLevel } = require('@opentelemetry/api');
const { OTLPTraceExporter } = require('@opentelemetry/exporter-trace-otlp-http');
const { OTLPMetricExporter } = require('@opentelemetry/exporter-metrics-otlp-http');
const { SequelizeInstrumentation } = require('opentelemetry-instrumentation-sequelize');
const { getNodeAutoInstrumentations } = require('@opentelemetry/auto-instrumentations-node');
const { PeriodicExportingMetricReader } = require('@opentelemetry/sdk-metrics');
const { Resource } = require('@opentelemetry/resources');
const { SemanticResourceAttributes } = require('@opentelemetry/semantic-conventions');

function init(options = {}) {
  const endpoint = options.endpoint || 'http://localhost:4318';
  const serviceName = options.serviceName || process.env.OTEL_SERVICE_NAME || 'default';

  if (!options.endpoint) {
    console.warn('[traceapm] Warning: No collector endpoint provided. Using default.');
  }
  if (!options.serviceName && !process.env.OTEL_SERVICE_NAME) {
    console.warn('[traceapm] Warning: No service name provided. Using default.');
  }

  diag.setLogger(new DiagConsoleLogger(), DiagLogLevel.ERROR);

  const traceExporter = new OTLPTraceExporter({
    url: endpoint + '/v1/traces',
  });

  const metricExporter = new OTLPMetricExporter({
    url: endpoint + '/v1/metrics',
  });

  const sequelizeInstrumentation = new SequelizeInstrumentation({
    enhancedDatabaseReporting: true,
  });

  const sdk = new NodeSDK({
    traceExporter,
    metricReader: new PeriodicExportingMetricReader({ exporter: metricExporter }),
    instrumentations: [getNodeAutoInstrumentations(), sequelizeInstrumentation],
    resource: new Resource({
      [SemanticResourceAttributes.SERVICE_NAME]: serviceName,
      ...options.attributes,
    }),
  });

  sdk.start();
}

module.exports = { init };