Log exporter to Opentelemetry Collector

[leonard-henriquez]

I am trying to send logs from my typescript codebase to the opentelemetry collector (to finally send them to Datadog).
I have succeeded to use the new OpenTelemetry Logs SDK to send logs to the console but I can't find an exporter to send them to the collector.
Is there something that I'm missing? Is it just that it has not been developed yet? Are there other packages that allow to to do that?
Thank you

// setup
const loggerProvider = new LoggerProvider();
loggerProvider.addLogRecordProcessor(
  new SimpleLogRecordProcessor(new ConsoleLogRecordExporter())
);
logs.setGlobalLoggerProvider(loggerProvider);

// usage
const logger = logs.getLogger('default');
logger.emit({ body })

[marr]

I'm at the same point and found the answer here #5180 (comment).

The OTLP exporter is still being developed apparently.

[pichlermarc]

That's not correct - the question there is for a stable SDK. One can use it just fine, but the version is in the 0.x range which means the API is just not stable yet.

[marr]

Makes sense. I was able to get an example built using the unstable packages.

I did something like this:

import logsAPI from '@opentelemetry/api-logs';
import { OTLPLogExporter } from '@opentelemetry/exporter-logs-otlp-grpc';
import {
  LoggerProvider,
  SimpleLogRecordProcessor,
  ConsoleLogRecordExporter,
  // BatchLogRecordProcessor,
} from '@opentelemetry/sdk-logs';

// To start a logger, you first need to initialize the Logger provider.
const loggerProvider = new LoggerProvider({
  resource: {
    attributes: {
      'service.name': 'test-service',
    }
  }
});
// Add a processor to export log record
loggerProvider.addLogRecordProcessor(
  new SimpleLogRecordProcessor(new ConsoleLogRecordExporter())
);

const loggerExporter = new OTLPLogExporter();
loggerProvider.addLogRecordProcessor(
  new SimpleLogRecordProcessor(loggerExporter)
);

//  To create a log record, you first need to get a Logger instance
const logger = loggerProvider.getLogger('default');

// You can also use global singleton
// logsAPI.logs.setGlobalLoggerProvider(loggerProvider);

// emit a log record
logger.emit({
  severityNumber: logsAPI.SeverityNumber.INFO,
  severityText: 'INFO',
  body: 'this is a log record body',
  attributes: { 'log.type': 'LogRecord' },
});

However, I found better logging using OpenTelemetryTransportV3 from @opentelemetry/winston-transport.

import winston, { format } from 'winston';
import {OpenTelemetryTransportV3} from '@opentelemetry/winston-transport';

const logger = winston.createLogger({
  level: 'info',
  // format: format.combine(winston.format.json(), format.errors({ stack: true })),
  format: format.combine(format.json(), format.timestamp(), format.errors({ stack: true })),
  // defaultMeta: { service: 'test-service' },
  transports: [
    new OpenTelemetryTransportV3(),
    new winston.transports.Console({
      format: winston.format.cli(),
      // format: winston.format.prettyPrint(),
    }),
  ],
});

logger.warn('this is a log record body', { 'log.type': 'LogRecord' });
const error = new Error('this is an error message');
logger.error('some xxx', error);
// logger.error('Something went wrong', { stack: error.stack, message: error.message });
// logger.info('foo', { service: 'bar' });
// logger.info('\x1b[36msometext\x1b[0m')

[pichlermarc]

Hi, thanks for reaching out. 🙂

You can use any of these three packages to export to the OTel collector:

• https://www.npmjs.com/package/@opentelemetry/exporter-logs-otlp-proto
• https://www.npmjs.com/package/@opentelemetry/exporter-logs-otlp-http
• https://www.npmjs.com/package/@opentelemetry/exporter-logs-otlp-grpc