How to monitor Node.js applications using OpenTelemetry and Prometheus?

const { NodeSDK } = require('@opentelemetry/sdk-node');
const { getNodeAutoInstrumentations } = require('@opentelemetry/auto-instrumentations-node');
const { PrometheusExporter } = require('@opentelemetry/exporter-prometheus');

const prometheusExporter = new PrometheusExporter({ port: 9091, endpoint: '/metrics' }, () => {
  console.log('Prometheus scrape endpoint: http://localhost:9091/metrics');
});

const sdk = new NodeSDK({
  metricReader: prometheusExporter,
  instrumentations: [getNodeAutoInstrumentations()],
});

sdk.start();