otlp-logger

Sends logs in the OpenTelemetry Log Data Model to an OTLP logs collector.

Install

npm i otlp-logger

Configuration

Protocol

can be set to http/protobuf, grpc, http or console by using

• env var OTEL_EXPORTER_OTLP_PROTOCOL
• env var OTEL_EXPORTER_OTLP_LOGS_PROTOCOL
• setting the exporterProtocol option

Settings configured programmatically take precedence over environment variables. Per-signal environment variables take precedence over non-per-signal environment variables. This principle applies to all the configurations in this module.

If no protocol is specified, http/protobuf is used as a default.

Exporter settings

Collector URL

Set either of the following environment variables: OTEL_EXPORTER_OTLP_LOGS_ENDPOINT, OTEL_EXPORTER_OTLP_ENDPOINT

Protocol-specific exporter configuration

http/protobuf

Env vars in README

grpc

Environment Variable Configuration

http

Env vars in README

Processor-specific configuration

If batch log processor is selected (is default), it can be configured using env vars described in the OpenTelemetry specification

Options

When using the transport, the following options can be used to configure the transport programmatically:

• loggerName: name to be used by the OpenTelemetry logger
• serviceVersion: version to be used by the OpenTelemetry logger
• resourceAttributes: Object containing resource attributes. Optional
• logRecordProcessorOptions: a single object or an array of objects specifying the LogProcessor and LogExporter types and constructor params. Optional

Usage

Minimalistic example

Make sure you have access to an OTEL collector.

To start quickly, create a minimal configuration for OTEL collector in the otel-collector-config.yaml file:

receivers:
  otlp:
    protocols:
      grpc:

exporters:
  file:
    path: ./etc/test-logs/otlp-logs.log
    flush_interval: 1

  logging:
    verbosity: basic
  
processors:
  batch:

service:
  pipelines:
    logs:
      receivers: [otlp]
      processors: []
      exporters: [logging, file]

The collector can then be ran with:

docker run --volume=$(pwd)/otel-collector-config.yaml:/etc/otel-collector-config.yaml:rw --volume=/tmp/test-logs:/etc/test-logs:rw -p 4317:4317 -d otel/opentelemetry-collector-contrib:latest --config=/etc/otel-collector-config.yaml

Create an index.js file containing

const { getOtlpLogger } = require('otlp-logger')

const logger = getOtlpLogger({
  loggerName: 'test',
  serviceVersion: '1.0.0'
})

logger.emit({
  severityNumber: 1,
  severityText: 'TRACE',
  body: 'test',
  timestamp: Date.now()
})

Run the service setting the OTEL_EXPORTER_OTLP_LOGS_ENDPOINT and OTEL_RESOURCE_ATTRIBUTES env vars

OTEL_EXPORTER_OTLP_LOGS_PROTOCOL='grpc' OTEL_EXPORTER_OTLP_LOGS_ENDPOINT=http://localhost:4317 OTEL_RESOURCE_ATTRIBUTES="service.name=my-service,service.version=1.2.3" node index.js

License

MIT