How add PrometheusExporter for NodeSDK traceExporter with opentelemetry js?

Question

I just started learning opentelemetry-js.
I have a node.js application.
for it I wrote a test file for opentelemetry-js.

instrumentation.js

const { NodeSDK } = require('@opentelemetry/sdk-node');
const { ConsoleSpanExporter } = require('@opentelemetry/sdk-trace-node');
const { getNodeAutoInstrumentations } = require('@opentelemetry/auto-instrumentations-node');
const { PeriodicExportingMetricReader, ConsoleMetricExporter, MeterProvider } = require('@opentelemetry/sdk-metrics');
const { PrometheusExporter } = require('@opentelemetry/exporter-prometheus');

const options = {port: 9464};
const exporter = new PrometheusExporter(options);

const consoleExporter = new ConsoleSpanExporter()

const sdk = new NodeSDK({
    traceExporter: consoleExporter,
    metricReader: new PeriodicExportingMetricReader({
        exporter: new ConsoleMetricExporter()
    }),
    instrumentations: [getNodeAutoInstrumentations()]
});

sdk.start()

Data on the server comes to the console.

{
  traceId: '2b366787acd87deea0e1de4e38f73469',
  parentId: undefined,
  traceState: undefined,
  name: 'fs statSync',
  id: '9807414f70b27f7d',
  kind: 0,
  timestamp: 1689777151629000,
  duration: 12,
  attributes: {},
  status: { code: 0 },
  events: [],
  links: []
}
{
  traceId: 'b74140f2610eb31277a4874317971602',
  parentId: '91529e125f5e27ed',
  traceState: undefined,
  name: 'middleware - query',
  id: '5e34627c252e58d9',
  kind: 0,
  timestamp: 1689777154416000,
  duration: 1141,
  attributes: {
    'http.route': '/',
    'express.name': 'query',
    'express.type': 'middleware'
  },
  status: { code: 0 },
  events: [],
  links: []
}

I installed a module for prometeus

const { PrometheusExporter } = require('@opentelemetry/exporter-prometheus');

The example for this module provides an example of creating metrics through the MeterProvider

const meterProvider = new MeterProvider();
meterProvider.addMetricReader(exporter);

I can get the metrics that I add using the meterProvider methods.
But I can't replace the output to the data console for the express application. I tried to include an exporter for traceExporter instead of consoleExporter but it didn't work.

Here is my not working code

const { NodeSDK } = require('@opentelemetry/sdk-node');
const { ConsoleSpanExporter } = require('@opentelemetry/sdk-trace-node');
const { getNodeAutoInstrumentations } = require('@opentelemetry/auto-instrumentations-node');
const { PeriodicExportingMetricReader, ConsoleMetricExporter, MeterProvider } = require('@opentelemetry/sdk-metrics');
const { PrometheusExporter } = require('@opentelemetry/exporter-prometheus');

const options = {port: 9464};
const exporter = new PrometheusExporter(options);

const meterProvider = new MeterProvider();
meterProvider.addMetricReader(exporter);

const consoleExporter = new ConsoleSpanExporter()

const sdk = new NodeSDK({
    traceExporter: exporter,
    metricReader: new PeriodicExportingMetricReader({
        exporter: new ConsoleMetricExporter()
    }),
    instrumentations: [getNodeAutoInstrumentations()]
});

sdk.start()

how can i send the data that comes in the console to the server for prometeus ?

Or what connection sequence should be in order to pass data to meterProvider ?

Or how can I connect a callback to traceExporter to add the data I need to meterProvider ?

Because I can use it to create metrics and send them. But I can't get data from the console.

const meter = meterProvider.getMeter('example-prometheus');
const counter = meter.createCounter('metric_name', {
    description: 'Example of a counter'
});
counter.add(10, { pid: process.pid });

Answer 1

Is this not the case to use the metricReader as the exporter?

// Add your port and startServer to the Prometheus options
const options = { port: 8111 };
const exporter = new PrometheusExporter(options);

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

sdk.start();