Module: Splunk::Otel

Defined in:
lib/splunk/otel.rb,
lib/splunk/otel/common.rb,
lib/splunk/otel/logging.rb,
lib/splunk/otel/version.rb,
lib/splunk/otel/proprietary_exporters.rb,
lib/splunk/otel/instrumentation/action_pack.rb,
lib/splunk/otel/instrumentation/rack/middleware.rb,
lib/splunk/otel/instrumentation/action_pack/railtie.rb,
lib/splunk/otel/instrumentation/action_pack/version.rb,
lib/splunk/otel/instrumentation/action_pack/instrumentation.rb

Overview

main module for application startup configuration

Defined Under Namespace

Modules: Common, ExporterExtensions, Instrumentation, Logging, Rack Classes: Error

Constant Summary collapse

VERSION = 
"0.2.0"

Class Method Summary collapse

Class Method Details

.configure(service_name: ENV.fetch("OTEL_SERVICE_NAME", "unnamed-ruby-service"), auto_instrument: false, trace_response_header_enabled: ENV.fetch("SPLUNK_TRACE_RESPONSE_HEADER_ENABLED", "true")) {|configurator| ... } ⇒ Object

Configures the OpenTelemetry SDK and instrumentation with Splunk defaults.

Example usage:

Without a block defaults are installed without any instrumentation

  Splunk::Otel.configure

Install instrumentation individually with optional config

  Splunk::Otel.configure do |c|
    c.use 'OpenTelemetry::Instrumentation::Faraday', tracer_middleware: SomeMiddleware
  end

Install all instrumentation with optional config

  Splunk::Otel.configure do |c|
    c.use_all 'OpenTelemetry::Instrumentation::Faraday' => { tracer_middleware: SomeMiddleware }
  end

Add a span processor

  Splunk::Otel.configure do |c|
    c.add_span_processor SpanProcessor.new(SomeExporter.new)
  end

Configure everything

  Splunk::Otel.configure do |c|
    c.logger = Logger.new(File::NULL)
    c.add_span_processor SpanProcessor.new(SomeExporter.new)
    c.use_all
  end

Yield Parameters:

  • configurator (Configurator) —

    Yields a configurator to the provided block



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# File 'lib/splunk/otel.rb', line 55

def configure(service_name: ENV.fetch("OTEL_SERVICE_NAME", "unnamed-ruby-service"),
              auto_instrument: false,
              trace_response_header_enabled: ENV.fetch("SPLUNK_TRACE_RESPONSE_HEADER_ENABLED", "true"))
  @trace_response_header_enabled = to_boolean(trace_response_header_enabled)

  set_defaults

  # run SDK's setup function
  OpenTelemetry::SDK.configure do |configurator|
    class << configurator
      include Splunk::Otel::ExporterExtensions
    end

    configurator.service_name = service_name
    configurator.resource = OpenTelemetry::SDK::Resources::Resource.create(
      "splunk.distro.version" => Splunk::Otel::VERSION
    )

    configurator.use_all if auto_instrument
    yield configurator if block_given?
  end

  # set span limits to GDI defaults if not set by the user
  OpenTelemetry.tracer_provider.span_limits = gdi_span_limits

  verify_service_name
end

.default_env_vars(env) ⇒ Object

set environment varaible default’s if the user hasn’t set them



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# File 'lib/splunk/otel.rb', line 163

def default_env_vars(env)
  env.each do |k, v|
    ENV[k] = v if ENV[k].nil?
  end
end

.gdi_span_limits ⇒ Object 



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# File 'lib/splunk/otel.rb', line 147

def gdi_span_limits
  infinite_defaults = { "OTEL_SPAN_ATTRIBUTE_COUNT_LIMIT" => :attribute_count_limit,
                        "OTEL_SPAN_EVENT_COUNT_LIMIT" => :event_count_limit,
                        "OTEL_SPAN_LINK_COUNT_LIMIT" => :link_count_limit,
                        "OTEL_EVENT_ATTRIBUTE_COUNT_LIMIT" => :event_attribute_count_limit,
                        "OTEL_LINK_ATTRIBUTE_COUNT_LIMIT" => :link_attribute_count_limit }

  defaults = {}
  infinite_defaults.each do |k, v|
    defaults[v] = Float::INFINITY if ENV[k].nil?
  end

  OpenTelemetry::SDK::Trace::SpanLimits.new(**defaults)
end

.service_name_warning ⇒ Object 



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# File 'lib/splunk/otel.rb', line 183

def service_name_warning
  "    service.name attribute is not set, your service is unnamed and will be difficult to identify.\n    set your service name using the OTEL_SERVICE_NAME environment variable.\n    E.g. `OTEL_SERVICE_NAME=\"<YOUR_SERVICE_NAME_HERE>\"`\n  WARNING\nend\n"

.set_access_token_header ⇒ Object

add the access token header if the env variable is set



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# File 'lib/splunk/otel.rb', line 125

def set_access_token_header
  splunk_access_token = ENV.fetch("SPLUNK_ACCESS_TOKEN", nil)
  return if splunk_access_token.nil?

  access_header = "x-sf-token=#{splunk_access_token}"
  headers = ENV.fetch("OTEL_EXPORTER_OTLP_HEADERS", nil)
  ENV["OTEL_EXPORTER_OTLP_HEADERS"] = if headers.to_s.empty?
                                        access_header
                                      else
                                        "#{headers},#{access_header}"
                                      end
end

.set_default_exporter ⇒ Object 



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# File 'lib/splunk/otel.rb', line 98

def set_default_exporter
  set_endpoint
  default_env_vars({ "OTEL_EXPORTER_OTLP_TRACES_COMPRESSION" => "gzip",
                     "OTEL_EXPORTER_OTLP_COMPRESSION" => "gzip",
                     "OTEL_TRACES_EXPORTER" => "otlp" })
end

.set_default_propagators ⇒ Object 



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# File 'lib/splunk/otel.rb', line 138

def set_default_propagators
  default_env_vars({ "OTEL_PROPAGATORS" => "tracecontext,baggage" })
end

.set_default_span_limits ⇒ Object 



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# File 'lib/splunk/otel.rb', line 142

def set_default_span_limits
  default_env_vars({ "OTEL_SPAN_LINK_COUNT_LIMIT" => "1000",
                     "OTEL_RUBY_SPAN_ATTRIBUTE_VALUE_LENGTH_LIMIT" => "12000" })
end

.set_defaults ⇒ Object 



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# File 'lib/splunk/otel.rb', line 83

def set_defaults
  set_default_propagators
  set_access_token_header
  set_default_exporter
  set_default_span_limits
end

.set_endpoint ⇒ Object 



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# File 'lib/splunk/otel.rb', line 105

def set_endpoint
  traces_endpoint = ENV.fetch("OTEL_EXPORTER_OTLP_TRACES_ENDPOINT", nil)
  endpoint = ENV.fetch("OTEL_EXPORTER_OTLP_ENDPOINT", nil)
  splunk_realm = ENV.fetch("SPLUNK_REALM", nil)

  # if user hasn't set traces endpoint or endpoint but has set the realm then
  # set the endpoints to be https://api.<SPLUNK_REALM>.signalfx.com
  # if either endpoint variable was set by the user then use those even if
  # they've also set SPLUNK_REALM
  return unless traces_endpoint.to_s.empty?
  return unless endpoint.to_s.empty?

  ENV["OTEL_EXPORTER_OTLP_TRACES_ENDPOINT"] = if splunk_realm.to_s.empty? || splunk_realm.to_s.eql?("none")
                                                "http://localhost:4318/v1/traces"
                                              else
                                                "https://ingest.#{splunk_realm}.signalfx.com/v2/trace/otlp"
                                              end
end

.to_boolean(val) ⇒ Object 



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# File 'lib/splunk/otel.rb', line 169

def to_boolean(val)
  # val could already be a boolean so just return the value if it is already
  # true or false
  case val
  when true then true
  when false then false
  else
    !%w[false
        no
        f
        0].include?(val.strip.downcase)
  end
end

.trace_response_header_enabled ⇒ Object

Returns the value of attribute trace_response_header_enabled.



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# File 'lib/splunk/otel.rb', line 16

def trace_response_header_enabled
  @trace_response_header_enabled
end

.verify_service_name ⇒ Object

verify ‘service.name` is set and print a warning if it is still the default



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# File 'lib/splunk/otel.rb', line 91

def verify_service_name
  provider_resource = OpenTelemetry.tracer_provider.instance_variable_get(:@resource)
  resource_attributes = provider_resource.instance_variable_get(:@attributes)
  service_name = resource_attributes[OpenTelemetry::SemanticConventions::Resource::SERVICE_NAME]
  OpenTelemetry.logger.warn service_name_warning if service_name == "unknown_service"
end