opentelemetry-exporter-jaeger

The opentelemetry-exporter-jaeger gem provides Jaeger exporters for OpenTelemetry for Ruby. Using opentelemetry-exporter-jaeger, an application can configure OpenTelemetry to export collected tracing data to Jaeger. Two exporters are included: the AgentExporter exports in Thrift Compact format over UDP to the Jaeger agent; and the CollectorExporter exports in Thrift Binary format over HTTP to the Jaeger 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 and metrics from your application. You can analyze them using Prometheus, Jaeger, and other observability tools.

How does this gem fit in?

The opentelemetry-exporter-jaeger gem is a plugin that provides Jaeger Tracing export. To export to Jaeger, an application can include this gem along with opentelemetry-sdk, and configure the SDK to use the provided Jaeger exporter as a span processor.

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

How do I get started?

Install the gem using:

gem install opentelemetry-sdk
gem install opentelemetry-exporter-jaeger

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

Then, configure the SDK to use a Jaeger exporter as a span processor, and use the OpenTelemetry interfaces to produces traces and other information. Following is a basic example for the AgentExporter.

require 'opentelemetry/sdk'
require 'opentelemetry/exporter/jaeger'

# Configure the sdk with the Jaeger collector exporter
ENV['OTEL_TRACES_EXPORTER'] = 'jaeger'

ENV['OTEL_SERVICE_NAME'] = 'jaeger-example'
ENV['OTEL_SERVICE_VERSION'] = '0.6.0'

# The exporter will connect to localhost:6831 by default. To change:
# ENV['OTEL_EXPORTER_JAEGER_AGENT_HOST'] = 'some.other.host'
# ENV['OTEL_EXPORTER_JAEGER_AGENT_PORT'] = 12345

# The SDK reads the environment for configuration, so no additional configuration is needed:
OpenTelemetry::SDK.configure

# If you need to use the Jaeger Agent exporter, you will need to configure many things manually:
# OpenTelemetry::SDK.configure do |c|
#   c.add_span_processor(
#     OpenTelemetry::SDK::Trace::Export::BatchSpanProcessor.new(
#       OpenTelemetry::Exporter::Jaeger::AgentExporter.new(host: '127.0.0.1', port: 6831)
#     )
#   )
# end

# To start a trace you need to get a Tracer from the TracerProvider
tracer = OpenTelemetry.tracer_provider.tracer('my_app_or_gem', '0.1.0')

# create a span
tracer.in_span('foo') do |span|
  # set an attribute
  span.set_attribute('platform', 'osx')
  # add an event
  span.add_event('event in bar')
  # create bar as child of foo
  tracer.in_span('bar') do |child_span|
    # inspect the span
    pp child_span
  end
end

For additional examples, see the examples on github.

How can I configure the Jaeger exporter?

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

Parameter	Environment variable	Default
`host:`	`OTEL_EXPORTER_JAEGER_AGENT_HOST`	`"localhost"`
`port:`	`OTEL_EXPORTER_JAEGER_AGENT_PORT`	`6831`
`max_packet_size:`		65000

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

Parameter	Environment variable	Default
`endpoint:`	`OTEL_EXPORTER_JAEGER_ENDPOINT`	`"http://localhost:14268/api/traces"`
`username:`	`OTEL_EXPORTER_JAEGER_USER`	`nil`
`password:`	`OTEL_EXPORTER_JAEGER_PASSWORD`	`nil`
`ssl_verify_mode:`	`OTEL_RUBY_EXPORTER_JAEGER_SSL_VERIFY_PEER` or	`OpenSSL::SSL:VERIFY_PEER`
	`OTEL_RUBY_EXPORTER_JAEGER_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-jaeger gem source is on github, along with related gems including opentelemetry-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-jaeger gem is distributed under the Apache 2.0 license. See LICENSE for more information.