debian-mirror-gitlab/lib/gitlab/metrics/web_transaction.rb
2021-12-11 22:18:48 +05:30

136 lines
4.3 KiB
Ruby

# frozen_string_literal: true
module Gitlab
module Metrics
# Exclusive transaction-type metrics for web servers (including Web/Api/Git
# fleet). One instance of this class is created for each request going
# through the Rack metric middleware. Any metrics dispatched with this
# instance include metadata such as controller, action, feature category,
# etc.
class WebTransaction < Transaction
THREAD_KEY = :_gitlab_metrics_transaction
BASE_LABEL_KEYS = %i(controller action feature_category).freeze
CONTROLLER_KEY = 'action_controller.instance'
ENDPOINT_KEY = 'api.endpoint'
ALLOWED_SUFFIXES = Set.new(%w[json js atom rss xml zip])
SMALL_BUCKETS = [0.1, 0.25, 0.5, 1.0, 2.5, 5.0].freeze
class << self
def current
Thread.current[THREAD_KEY]
end
def prometheus_metric(name, type, &block)
fetch_metric(type, name) do
# set default metric options
docstring "#{name.to_s.humanize} #{type}"
evaluate(&block)
# always filter sensitive labels and merge with base ones
label_keys BASE_LABEL_KEYS | (label_keys - ::Gitlab::Metrics::Transaction::FILTERED_LABEL_KEYS)
end
end
end
def initialize(env)
super()
@env = env
end
def run
Thread.current[THREAD_KEY] = self
started_at = System.monotonic_time
status, _, _ = retval = yield
finished_at = System.monotonic_time
duration = finished_at - started_at
record_duration_if_needed(status, duration)
retval
ensure
Thread.current[THREAD_KEY] = nil
end
def labels
return @labels if @labels
# memoize transaction labels only source env variables were present
@labels = if @env[CONTROLLER_KEY]
labels_from_controller || {}
elsif @env[ENDPOINT_KEY]
labels_from_endpoint || {}
end
@labels || {}
end
private
def record_duration_if_needed(status, duration)
return unless Gitlab::Metrics.record_duration_for_status?(status)
observe(:gitlab_transaction_duration_seconds, duration) do
buckets SMALL_BUCKETS
end
end
def labels_from_controller
controller = @env[CONTROLLER_KEY]
action = "#{controller.action_name}"
# Devise exposes a method called "request_format" that does the below.
# However, this method is not available to all controllers (e.g. certain
# Doorkeeper controllers). As such we use the underlying code directly.
suffix = controller.request.format.try(:ref).to_s
# Sometimes the request format is set to silly data such as
# "application/xrds+xml" or actual URLs. To prevent such values from
# increasing the cardinality of our metrics, we limit the number of
# possible suffixes.
if suffix && ALLOWED_SUFFIXES.include?(suffix)
action = "#{action}.#{suffix}"
end
{ controller: controller.class.name, action: action, feature_category: feature_category }
end
def labels_from_endpoint
endpoint = @env[ENDPOINT_KEY]
begin
route = endpoint.route
rescue StandardError
# endpoint.route is calling env[Grape::Env::GRAPE_ROUTING_ARGS][:route_info]
# but env[Grape::Env::GRAPE_ROUTING_ARGS] is nil in the case of a 405 response
# so we're rescuing exceptions and bailing out
end
if route
path = endpoint_paths_cache[route.request_method][route.path]
{ controller: 'Grape', action: "#{route.request_method} #{path}", feature_category: feature_category }
end
end
def endpoint_paths_cache
@endpoint_paths_cache ||= Hash.new do |hash, http_method|
hash[http_method] = Hash.new do |inner_hash, raw_path|
inner_hash[raw_path] = endpoint_instrumentable_path(raw_path)
end
end
end
def endpoint_instrumentable_path(raw_path)
raw_path.sub('(.:format)', '').sub('/:version', '')
end
def feature_category
::Gitlab::ApplicationContext.current_context_attribute(:feature_category) || ::Gitlab::FeatureCategories::FEATURE_CATEGORY_DEFAULT
end
end
end
end