gitlab-org--gitlab-foss/lib/gitlab/metrics/prometheus.rb

105 lines
2.8 KiB
Ruby

# frozen_string_literal: true
module Gitlab
module Metrics
module Prometheus
extend ActiveSupport::Concern
REGISTRY_MUTEX = Mutex.new
PROVIDER_MUTEX = Mutex.new
class_methods do
include Gitlab::Utils::StrongMemoize
def metrics_folder_present?
multiprocess_files_dir = ::Prometheus::Client.configuration.multiprocess_files_dir
multiprocess_files_dir &&
::Dir.exist?(multiprocess_files_dir) &&
::File.writable?(multiprocess_files_dir)
end
def prometheus_metrics_enabled?
strong_memoize(:prometheus_metrics_enabled) do
prometheus_metrics_enabled_unmemoized
end
end
def reset_registry!
clear_memoization(:registry)
REGISTRY_MUTEX.synchronize do
::Prometheus::Client.cleanup!
::Prometheus::Client.reset!
end
end
def registry
strong_memoize(:registry) do
REGISTRY_MUTEX.synchronize do
strong_memoize(:registry) do
::Prometheus::Client.registry
end
end
end
end
def counter(name, docstring, base_labels = {})
safe_provide_metric(:counter, name, docstring, base_labels)
end
def summary(name, docstring, base_labels = {})
safe_provide_metric(:summary, name, docstring, base_labels)
end
def gauge(name, docstring, base_labels = {}, multiprocess_mode = :all)
safe_provide_metric(:gauge, name, docstring, base_labels, multiprocess_mode)
end
def histogram(name, docstring, base_labels = {}, buckets = ::Prometheus::Client::Histogram::DEFAULT_BUCKETS)
safe_provide_metric(:histogram, name, docstring, base_labels, buckets)
end
def error_detected!
set_error!(true)
end
def clear_errors!
set_error!(false)
end
def set_error!(status)
clear_memoization(:prometheus_metrics_enabled)
PROVIDER_MUTEX.synchronize do
@error = status
end
end
private
def safe_provide_metric(method, name, *args)
metric = provide_metric(name)
return metric if metric
PROVIDER_MUTEX.synchronize do
provide_metric(name) || registry.method(method).call(name, *args)
end
end
def provide_metric(name)
if prometheus_metrics_enabled?
registry.get(name)
else
NullMetric.instance
end
end
def prometheus_metrics_enabled_unmemoized
!error? && metrics_folder_present? && Gitlab::CurrentSettings.prometheus_metrics_enabled || false
end
end
end
end
end