opentelemetry-exporter-otlp-logs

The opentelemetry-exporter-otlp-logs gem provides an OTLP logs exporter for OpenTelemetry for Ruby. Using opentelemetry-exporter-otlp-logs, an application can configure OpenTelemetry to export collected log record data to the OpenTelemetry Collector.

What is OpenTelemetry?

OpenTelemetry is an open source observability framework, providing a general-purpose API, SDK, and related tools required for the instrumentation of cloud-native software, frameworks, and libraries.

OpenTelemetry provides a single set of APIs, libraries, agents, and collector services to capture distributed traces, metrics and logs from your application. You can analyze them using Prometheus, Jaeger, and other observability tools.

How does this gem fit in?

The opentelemetry-exporter-otlp-logs gem is a plugin that provides OTLP export. To export to the OpenTelemetry Collector, an application can include this gem along with opentelemetry-logs-sdk and configure the SDK to use the provided OTLP exporter with a log record processor.

Generally, libraries that produce telemetry data should avoid depending directly on specific exporter, deferring that choice to the application developer.

Supported protocol version

This gem supports the v0.20.0 release of OTLP.

How do I get started?

Install the gem using:


gem install opentelemetry-logs-sdk
gem install opentelemetry-exporter-otlp-logs

Or, if you use bundler, include opentelemetry-sdk in your Gemfile.

Then, configure the SDK to use the OTLP exporter as a log record processor, and use the OpenTelemetry interfaces to produce log records. The following is a basic example.

require 'opentelemetry-logs-sdk'
require 'opentelemetry/exporter/otlp_logs'

# Create a LoggerProvider
logger_provider = OpenTelemetry::SDK::Logs::LoggerProvider.new
# Create a batching processor configured to export to the OTLP exporter
processor = OpenTelemetry::SDK::Logs::Export::BatchLogRecordProcessor.new(OpenTelemetry::Exporter::OTLP::Logs::LogsExporter.new)
# Add the processor to the LoggerProvider
logger_provider.add_log_record_processor(processor)
# Access a Logger for your library from your LoggerProvider
logger = logger_provider.logger(name: 'my_app_or_gem', version: '0.1.0')

# Use your Logger to  emit a log record
logger.on_emit(
  timestamp: Time.now,
  severity_text: 'INFO',
  body: 'Thuja plicata',
  attributes: { 'cedar' => true },
)

logger_provider.shutdown

# You can also use your Logger to emit an event
logger.on_emit(
  timestamp: Time.now,
  severity_text: 'INFO',
  body: 'Picea sitchensis',
  attributes: { 'spruce' => true },
  event_name: 'TreeSpecies'
)

For additional examples, see the examples on github.

How can I configure the OTLP logs exporter?

The collector exporter can be configured explicitly in code, or via environment variables. The configuration parameters, environment variables, and defaults are shown below.

Parameter	Environment variable	Default
`endpoint:`	`OTEL_EXPORTER_OTLP_ENDPOINT`	`"http://localhost:4318/v1/logs"`
`certificate_file:`	`OTEL_EXPORTER_OTLP_CERTIFICATE`
`client_certificate_file`	`OTEL_EXPORTER_OTLP_CLIENT_CERTIFICATE`
`client_key_file`	`OTEL_EXPORTER_OTLP_CLIENT_KEY`
`headers:`	`OTEL_EXPORTER_OTLP_HEADERS`
`compression:`	`OTEL_EXPORTER_OTLP_COMPRESSION`	`"gzip"`
`timeout:`	`OTEL_EXPORTER_OTLP_TIMEOUT`	`10`
`ssl_verify_mode:`	`OTEL_RUBY_EXPORTER_OTLP_SSL_VERIFY_PEER` or	`OpenSSL::SSL:VERIFY_PEER`
	`OTEL_RUBY_EXPORTER_OTLP_SSL_VERIFY_NONE`

ssl_verify_mode: parameter values should be flags for server certificate verification: OpenSSL::SSL:VERIFY_PEER and OpenSSL::SSL:VERIFY_NONE are acceptable. These values can also be set using the appropriately named environment variables as shown where VERIFY_PEER will take precedence over VERIFY_NONE. Please see the Net::HTTP docs for more information about these flags.

How can I get involved?

The opentelemetry-exporter-otlp-logs gem source is on github, along with related gems including opentelemetry-logs-sdk.

The OpenTelemetry Ruby gems are maintained by the OpenTelemetry-Ruby special interest group (SIG). You can get involved by joining us in GitHub Discussions or attending our weekly meeting. See the meeting calendar for dates and times. For more information on this and other language SIGs, see the OpenTelemetry community page.

License

The opentelemetry-exporter-otlp-logs gem is distributed under the Apache 2.0 license. See LICENSE for more information.

Working with Proto Definitions

The OTel community maintains a repository with protobuf definitions that language and collector implementors use to generate code.

Maintainers are expected to keep up to date with the latest version of protos. This guide will provide you with step-by-step instructions on updating the OTLP Logs Exporter gem with the latest definitions.

System Requirements

:warning: protoc 23.x changes the Ruby code generator to emit a serialized proto instead of a DSL. https://protobuf.dev/news/2023-04-20/. Please ensure you use protoc version 22.x in order to ensure we remain compatible with versions of protobuf prior to google-protobuf gem 3.18.

Upgrade Proto Definitions

Update the target otel-proto version in the Rakefile that matches a release tag in the proto repo, e.g.

  # Rakefile

  # https://github.com/open-telemetry/opentelemetry-proto/tree/v0.20.0
  PROTO_VERSION = `v0.20.0`

Generate the Ruby source files using rake:


$> bundle exec rake protobuf:generate

Run tests and fix any errors:


$> bundle exec rake test

Commit the changes and open a PR!