module Datadog::Tracing::Contrib::ActiveSupport::Cache::Instrumentation

def enabled? 

def enabled?
  Tracing.enabled? && Datadog.configuration.tracing[:active_support][:enabled]
end

def nested_multiread?

(see #nested_read?) 
def nested_multiread?
  current_span = Tracing.active_span
  current_span && current_span.name == Ext::SPAN_CACHE && current_span.resource == Ext::RESOURCE_CACHE_MGET
end

def nested_read?

This method checks if these two operations are nested.
Instrument both does not add any value.
In most of the cases, `#fetch()` and `#read()` calls are nested. 
def nested_read?
  current_span = Tracing.active_span
  current_span && current_span.name == Ext::SPAN_CACHE && current_span.resource == Ext::RESOURCE_CACHE_GET
end

def set_cache_key(span, single_key, multi_key) 

def set_cache_key(span, single_key, multi_key)
  if multi_key
    resolved_key = multi_key.map { |key| ::ActiveSupport::Cache.expand_cache_key(key) }
    cache_key = Core::Utils.truncate(resolved_key, Ext::QUANTIZE_CACHE_MAX_KEY_SIZE)
    span.set_tag(Ext::TAG_CACHE_KEY_MULTI, cache_key)
  else
    resolved_key = ::ActiveSupport::Cache.expand_cache_key(single_key)
    cache_key = Core::Utils.truncate(resolved_key, Ext::QUANTIZE_CACHE_MAX_KEY_SIZE)
    span.set_tag(Ext::TAG_CACHE_KEY, cache_key)
  end
end

def trace(action, store, key: nil, multi_key: nil)

Parameters:
  • multi_key (Array) -- list of redis cache keys. Used for actions with a multiple key locators.
  • key (Object) -- redis cache key. Used for actions with a single key locator.
  • action (String) -- type of cache operation. Will be set as the span resource. 
    • def trace(action, store, key: nil, multi_key: nil)
  return yield unless enabled?
  # create a new ``Span`` and add it to the tracing context
  Tracing.trace(
    Ext::SPAN_CACHE,
    span_type: Ext::SPAN_TYPE_CACHE,
    service: Datadog.configuration.tracing[:active_support][:cache_service],
    resource: action
  ) do |span|
    span.set_tag(Tracing::Metadata::Ext::TAG_COMPONENT, Ext::TAG_COMPONENT)
    span.set_tag(Tracing::Metadata::Ext::TAG_OPERATION, Ext::TAG_OPERATION_CACHE)
    if span.service != Datadog.configuration.service
      span.set_tag(Tracing::Contrib::Ext::Metadata::TAG_BASE_SERVICE, Datadog.configuration.service)
    end
    span.set_tag(Ext::TAG_CACHE_BACKEND, store) if store
    set_cache_key(span, key, multi_key)
    yield
  end
end