Class: Datadog::Tracing::Sampling::RateByServiceSampler

Inherits:
RateByKeySampler show all
Defined in:
lib/datadog/tracing/sampling/rate_by_service_sampler.rb

Overview

RateByServiceSampler samples different services at different rates

Constant Summary collapse

DEFAULT_KEY = 
'service:,env:'.freeze

Instance Attribute Summary

Attributes inherited from RateByKeySampler

#default_key

Instance Method Summary collapse

Methods inherited from RateByKeySampler

#default_sampler, #delete, #delete_if, #length, #resolve, #sample!, #sample?, #sample_rate, #update_all

Methods inherited from Sampler

#sample!, #sample?, #sample_rate

Constructor Details

#initialize(default_rate = 1.0, env: nil, decision: Datadog::Tracing::Sampling::Ext::Decision::DEFAULT) ⇒ RateByServiceSampler

Returns a new instance of RateByServiceSampler.



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# File 'lib/datadog/tracing/sampling/rate_by_service_sampler.rb', line 11

def initialize(default_rate = 1.0, env: nil, decision: Datadog::Tracing::Sampling::Ext::Decision::DEFAULT)
  super(
    DEFAULT_KEY,
    default_rate,
    decision: decision,
    &method(:key_for)
  )

  @env = env
end

Instance Method Details

#update(rate_by_service, decision: nil) ⇒ Object 



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# File 'lib/datadog/tracing/sampling/rate_by_service_sampler.rb', line 22

def update(rate_by_service, decision: nil)
  # Remove any old services
  delete_if { |key, _| key != DEFAULT_KEY && !rate_by_service.key?(key) }

  # Update each service rate
  update_all(rate_by_service, decision: decision)

  # Emit metric for service cache size
  Datadog.health_metrics.sampling_service_cache_length(length)
end